bgfx/src/renderer_mtl.cpp

/*
 * Copyright 2011-2025 Attila Kocsis. All rights reserved.
 * License: https://github.com/bkaradzic/bgfx/blob/master/LICENSE
 */

#include "bgfx_p.h"

#if BGFX_CONFIG_RENDERER_METAL

#define CA_PRIVATE_IMPLEMENTATION
#define MTL_PRIVATE_IMPLEMENTATION
#define NS_PRIVATE_IMPLEMENTATION
#include <metal-cpp/metal.hpp>

#include "renderer_mtl.h"
#include "renderer.h"
#include <bx/macros.h>

#if BX_PLATFORM_OSX
#	include <IOKit/IOKitLib.h>
#endif // BX_PLATFORM_OSX

#define UNIFORM_BUFFER_SIZE (8*1024*1024)

namespace bgfx { namespace mtl
{
	static char s_viewName[BGFX_CONFIG_MAX_VIEWS][BGFX_CONFIG_MAX_VIEW_NAME];

	inline void setViewType(ViewId _view, const bx::StringView _str)
	{
		if (BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION || BGFX_CONFIG_PROFILER) )
		{
			bx::memCopy(&s_viewName[_view][3], _str.getPtr(), _str.getLength() );
		}
	}

	struct PrimInfo
	{
		MTL::PrimitiveType m_type;
		uint32_t m_min;
		uint32_t m_div;
		uint32_t m_sub;
	};

	static const PrimInfo s_primInfo[] =
	{
		{ MTL::PrimitiveTypeTriangle,      3, 3, 0 },
		{ MTL::PrimitiveTypeTriangleStrip, 3, 1, 2 },
		{ MTL::PrimitiveTypeLine,          2, 2, 0 },
		{ MTL::PrimitiveTypeLineStrip,     2, 1, 1 },
		{ MTL::PrimitiveTypePoint,         1, 1, 0 },
	};
	static_assert(Topology::Count == BX_COUNTOF(s_primInfo) );

	static const char* s_attribName[] =
	{
		"a_position",
		"a_normal",
		"a_tangent",
		"a_bitangent",
		"a_color0",
		"a_color1",
		"a_color2",
		"a_color3",
		"a_indices",
		"a_weight",
		"a_texcoord0",
		"a_texcoord1",
		"a_texcoord2",
		"a_texcoord3",
		"a_texcoord4",
		"a_texcoord5",
		"a_texcoord6",
		"a_texcoord7",
	};
	static_assert(Attrib::Count == BX_COUNTOF(s_attribName) );

	static const char* s_instanceDataName[] =
	{
		"i_data0",
		"i_data1",
		"i_data2",
		"i_data3",
		"i_data4",
	};
	static_assert(BGFX_CONFIG_MAX_INSTANCE_DATA_COUNT == BX_COUNTOF(s_instanceDataName) );

	static const MTL::VertexFormat s_attribType[][4][2] = //type, count, normalized
	{
		{ // Uint8
			{ MTL::VertexFormatChar2,                 MTL::VertexFormatChar2Normalized       },
			{ MTL::VertexFormatChar2,                 MTL::VertexFormatChar2Normalized       },
			{ MTL::VertexFormatChar3,                 MTL::VertexFormatChar3Normalized       },
			{ MTL::VertexFormatChar4,                 MTL::VertexFormatChar4Normalized       },
		},
		{ // Uint8
			{ MTL::VertexFormatUChar2,                MTL::VertexFormatUChar2Normalized      },
			{ MTL::VertexFormatUChar2,                MTL::VertexFormatUChar2Normalized      },
			{ MTL::VertexFormatUChar3,                MTL::VertexFormatUChar3Normalized      },
			{ MTL::VertexFormatUChar4,                MTL::VertexFormatUChar4Normalized      },
		},
		{ // Uint10
			{ MTL::VertexFormatUInt1010102Normalized, MTL::VertexFormatUInt1010102Normalized },
			{ MTL::VertexFormatUInt1010102Normalized, MTL::VertexFormatUInt1010102Normalized },
			{ MTL::VertexFormatUInt1010102Normalized, MTL::VertexFormatUInt1010102Normalized },
			{ MTL::VertexFormatUInt1010102Normalized, MTL::VertexFormatUInt1010102Normalized },
		},
		{ // Int16
			{ MTL::VertexFormatShort2,                MTL::VertexFormatShort2Normalized      },
			{ MTL::VertexFormatShort2,                MTL::VertexFormatShort2Normalized      },
			{ MTL::VertexFormatShort3,                MTL::VertexFormatShort3Normalized      },
			{ MTL::VertexFormatShort4,                MTL::VertexFormatShort4Normalized      },
		},
		{ // Int16
			{ MTL::VertexFormatUShort2,               MTL::VertexFormatUShort2Normalized     },
			{ MTL::VertexFormatUShort2,               MTL::VertexFormatUShort2Normalized     },
			{ MTL::VertexFormatUShort3,               MTL::VertexFormatUShort3Normalized     },
			{ MTL::VertexFormatUShort4,               MTL::VertexFormatUShort4Normalized     },
		},
		{ // Half
			{ MTL::VertexFormatHalf2,                 MTL::VertexFormatHalf2                 },
			{ MTL::VertexFormatHalf2,                 MTL::VertexFormatHalf2                 },
			{ MTL::VertexFormatHalf3,                 MTL::VertexFormatHalf3                 },
			{ MTL::VertexFormatHalf4,                 MTL::VertexFormatHalf4                 },
		},
		{ // Float
			{ MTL::VertexFormatFloat,                 MTL::VertexFormatFloat                 },
			{ MTL::VertexFormatFloat2,                MTL::VertexFormatFloat2                },
			{ MTL::VertexFormatFloat3,                MTL::VertexFormatFloat3                },
			{ MTL::VertexFormatFloat4,                MTL::VertexFormatFloat4                },
		},
	};
	static_assert(AttribType::Count == BX_COUNTOF(s_attribType) );

	static const MTL::CullMode s_cullMode[] =
	{
		MTL::CullModeNone,
		MTL::CullModeFront,
		MTL::CullModeBack,
		MTL::CullModeNone
	};

	static const MTL::BlendFactor s_blendFactor[][2] =
	{
		{ MTL::BlendFactor(0),                      MTL::BlendFactor(0)                      }, // ignored
		{ MTL::BlendFactorZero,                     MTL::BlendFactorZero                     }, // ZERO
		{ MTL::BlendFactorOne,                      MTL::BlendFactorOne                      }, // ONE
		{ MTL::BlendFactorSourceColor,              MTL::BlendFactorSourceAlpha              }, // SRC_COLOR
		{ MTL::BlendFactorOneMinusSourceColor,      MTL::BlendFactorOneMinusSourceAlpha      }, // INV_SRC_COLOR
		{ MTL::BlendFactorSourceAlpha,              MTL::BlendFactorSourceAlpha              }, // SRC_ALPHA
		{ MTL::BlendFactorOneMinusSourceAlpha,      MTL::BlendFactorOneMinusSourceAlpha      }, // INV_SRC_ALPHA
		{ MTL::BlendFactorDestinationAlpha,         MTL::BlendFactorDestinationAlpha         }, // DST_ALPHA
		{ MTL::BlendFactorOneMinusDestinationAlpha, MTL::BlendFactorOneMinusDestinationAlpha }, // INV_DST_ALPHA
		{ MTL::BlendFactorDestinationColor,         MTL::BlendFactorDestinationAlpha         }, // DST_COLOR
		{ MTL::BlendFactorOneMinusDestinationColor, MTL::BlendFactorOneMinusDestinationAlpha }, // INV_DST_COLOR
		{ MTL::BlendFactorSourceAlphaSaturated,     MTL::BlendFactorOne                      }, // SRC_ALPHA_SAT
		{ MTL::BlendFactorBlendColor,               MTL::BlendFactorBlendColor               }, // FACTOR
		{ MTL::BlendFactorOneMinusBlendColor,       MTL::BlendFactorOneMinusBlendColor       }, // INV_FACTOR
	};

	static const MTL::BlendOperation s_blendEquation[] =
	{
		MTL::BlendOperationAdd,
		MTL::BlendOperationSubtract,
		MTL::BlendOperationReverseSubtract,
		MTL::BlendOperationMin,
		MTL::BlendOperationMax,
	};

	static const MTL::CompareFunction s_cmpFunc[] =
	{
		MTL::CompareFunctionAlways,
		MTL::CompareFunctionLess,
		MTL::CompareFunctionLessEqual,
		MTL::CompareFunctionEqual,
		MTL::CompareFunctionGreaterEqual,
		MTL::CompareFunctionGreater,
		MTL::CompareFunctionNotEqual,
		MTL::CompareFunctionNever,
		MTL::CompareFunctionAlways,
	};

	static const MTL::StencilOperation s_stencilOp[] =
	{
		MTL::StencilOperationZero,
		MTL::StencilOperationKeep,
		MTL::StencilOperationReplace,
		MTL::StencilOperationIncrementWrap,
		MTL::StencilOperationIncrementClamp,
		MTL::StencilOperationDecrementWrap,
		MTL::StencilOperationDecrementClamp,
		MTL::StencilOperationInvert,
	};

	static const MTL::SamplerAddressMode s_textureAddress[] =
	{
		MTL::SamplerAddressModeRepeat,
		MTL::SamplerAddressModeMirrorRepeat,
		MTL::SamplerAddressModeClampToEdge,
		MTL::SamplerAddressModeClampToZero,
	};

	static const MTL::SamplerMinMagFilter s_textureFilterMinMag[] =
	{
		MTL::SamplerMinMagFilterLinear,
		MTL::SamplerMinMagFilterNearest,
		MTL::SamplerMinMagFilterLinear,
	};

	static const MTL::SamplerMipFilter s_textureFilterMip[] =
	{
		MTL::SamplerMipFilterLinear,
		MTL::SamplerMipFilterNearest,
	};

	struct TextureFormatInfo
	{
		MTL::PixelFormat            m_fmt;
		MTL::PixelFormat            m_fmtSrgb;
		MTL::ReadWriteTextureTier   m_rwTier;
		MTL::TextureSwizzleChannels m_mapping;
		bool                      m_autoGetMipmap;
	};

BX_PRAGMA_DIAGNOSTIC_PUSH();
BX_PRAGMA_DIAGNOSTIC_IGNORED_CLANG("-Wunguarded-availability-new");

	static TextureFormatInfo s_textureFormat[] =
	{
#define $0 MTL::TextureSwizzleZero
#define $1 MTL::TextureSwizzleOne
#define $R MTL::TextureSwizzleRed
#define $G MTL::TextureSwizzleGreen
#define $B MTL::TextureSwizzleBlue
#define $A MTL::TextureSwizzleAlpha
		{ MTL::PixelFormatBC1_RGBA,              MTL::PixelFormatBC1_RGBA_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC1
		{ MTL::PixelFormatBC2_RGBA,              MTL::PixelFormatBC2_RGBA_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC2
		{ MTL::PixelFormatBC3_RGBA,              MTL::PixelFormatBC3_RGBA_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC3
		{ MTL::PixelFormatBC4_RUnorm,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC4
		{ MTL::PixelFormatBC5_RGUnorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC5
		{ MTL::PixelFormatBC6H_RGBFloat,         MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC6H
		{ MTL::PixelFormatBC7_RGBAUnorm,         MTL::PixelFormatBC7_RGBAUnorm_sRGB,   MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BC7
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ETC1
		{ MTL::PixelFormatETC2_RGB8,             MTL::PixelFormatETC2_RGB8_sRGB,       MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ETC2
		{ MTL::PixelFormatEAC_RGBA8,             MTL::PixelFormatEAC_RGBA8_sRGB,       MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ETC2A
		{ MTL::PixelFormatETC2_RGB8A1,           MTL::PixelFormatETC2_RGB8A1_sRGB,     MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ETC2A1
		{ MTL::PixelFormatEAC_R11Unorm,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // EACR11 UNORM
		{ MTL::PixelFormatEAC_R11Snorm,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // EACR11 SNORM
		{ MTL::PixelFormatEAC_RG11Unorm,         MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // EACRG11 UNORM
		{ MTL::PixelFormatEAC_RG11Snorm,         MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // EACRG11 SNORM
		{ MTL::PixelFormatPVRTC_RGB_2BPP,        MTL::PixelFormatPVRTC_RGB_2BPP_sRGB,  MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC12
		{ MTL::PixelFormatPVRTC_RGB_4BPP,        MTL::PixelFormatPVRTC_RGB_4BPP_sRGB,  MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC14
		{ MTL::PixelFormatPVRTC_RGBA_2BPP,       MTL::PixelFormatPVRTC_RGBA_2BPP_sRGB, MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC12A
		{ MTL::PixelFormatPVRTC_RGBA_4BPP,       MTL::PixelFormatPVRTC_RGBA_4BPP_sRGB, MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC14A
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC22
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // PTC24
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ATC
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ATCE
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ATCI
		{ MTL::PixelFormatASTC_4x4_LDR,          MTL::PixelFormatASTC_4x4_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC4x4
		{ MTL::PixelFormatASTC_5x4_LDR,          MTL::PixelFormatASTC_5x4_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC5x4
		{ MTL::PixelFormatASTC_5x5_LDR,          MTL::PixelFormatASTC_5x5_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC5x5
		{ MTL::PixelFormatASTC_6x5_LDR,          MTL::PixelFormatASTC_6x5_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC6x5
		{ MTL::PixelFormatASTC_6x6_LDR,          MTL::PixelFormatASTC_6x6_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC6x6
		{ MTL::PixelFormatASTC_8x5_LDR,          MTL::PixelFormatASTC_8x5_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC8x5
		{ MTL::PixelFormatASTC_8x6_LDR,          MTL::PixelFormatASTC_8x6_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC8x6
		{ MTL::PixelFormatASTC_8x8_LDR,          MTL::PixelFormatASTC_8x8_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC8x8
		{ MTL::PixelFormatASTC_10x5_LDR,         MTL::PixelFormatASTC_10x5_sRGB,       MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC10x5
		{ MTL::PixelFormatASTC_10x6_LDR,         MTL::PixelFormatASTC_10x6_sRGB,       MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC10x6
		{ MTL::PixelFormatASTC_10x8_LDR,         MTL::PixelFormatASTC_10x8_sRGB,       MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC10x8
		{ MTL::PixelFormatASTC_10x10_LDR,        MTL::PixelFormatASTC_10x10_sRGB,      MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC10x10
		{ MTL::PixelFormatASTC_12x10_LDR,        MTL::PixelFormatASTC_12x10_sRGB,      MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC12x10
		{ MTL::PixelFormatASTC_12x12_LDR,        MTL::PixelFormatASTC_12x12_sRGB,      MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // ASTC12x12
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // Unknown
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // R1
		{ MTL::PixelFormatA8Unorm,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // A8
		{ MTL::PixelFormatR8Unorm,               MTL::PixelFormatR8Unorm_sRGB,         MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // R8
		{ MTL::PixelFormatR8Sint,                MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // R8I
		{ MTL::PixelFormatR8Uint,                MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // R8U
		{ MTL::PixelFormatR8Snorm,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // R8S
		{ MTL::PixelFormatR16Unorm,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // R16
		{ MTL::PixelFormatR16Sint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // R16I
		{ MTL::PixelFormatR16Uint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // R16U
		{ MTL::PixelFormatR16Float,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // R16F
		{ MTL::PixelFormatR16Snorm,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // R16S
		{ MTL::PixelFormatR32Sint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier1,    { $R, $G, $B, $A }, false }, // R32I
		{ MTL::PixelFormatR32Uint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier1,    { $R, $G, $B, $A }, false }, // R32U
		{ MTL::PixelFormatR32Float,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier1,    { $R, $G, $B, $A }, false }, // R32F
		{ MTL::PixelFormatRG8Unorm,              MTL::PixelFormatRG8Unorm_sRGB,        MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG8
		{ MTL::PixelFormatRG8Sint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG8I
		{ MTL::PixelFormatRG8Uint,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG8U
		{ MTL::PixelFormatRG8Snorm,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG8S
		{ MTL::PixelFormatRG16Unorm,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG16
		{ MTL::PixelFormatRG16Sint,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG16I
		{ MTL::PixelFormatRG16Uint,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG16U
		{ MTL::PixelFormatRG16Float,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG16F
		{ MTL::PixelFormatRG16Snorm,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG16S
		{ MTL::PixelFormatRG32Sint,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG32I
		{ MTL::PixelFormatRG32Uint,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG32U
		{ MTL::PixelFormatRG32Float,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RG32F
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RGB8
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RGB8I
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RGB8U
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RGB8S
		{ MTL::PixelFormatRGB9E5Float,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // RGB9E5F
		{ MTL::PixelFormatBGRA8Unorm,            MTL::PixelFormatBGRA8Unorm_sRGB,      MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // BGRA8
		{ MTL::PixelFormatRGBA8Unorm,            MTL::PixelFormatRGBA8Unorm_sRGB,      MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // RGBA8
		{ MTL::PixelFormatRGBA8Sint,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // RGBA8I
		{ MTL::PixelFormatRGBA8Uint,             MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // RGBA8U
		{ MTL::PixelFormatRGBA8Snorm,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RGBA8S
		{ MTL::PixelFormatRGBA16Unorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RGBA16
		{ MTL::PixelFormatRGBA16Sint,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // RGBA16I
		{ MTL::PixelFormatRGBA16Uint,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, false }, // RGBA16U
		{ MTL::PixelFormatRGBA16Float,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // RGBA16F
		{ MTL::PixelFormatRGBA16Snorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RGBA16S
		{ MTL::PixelFormatRGBA32Sint,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // RGBA32I
		{ MTL::PixelFormatRGBA32Uint,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // RGBA32U
		{ MTL::PixelFormatRGBA32Float,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTier2,    { $R, $G, $B, $A }, true  }, // RGBA32F
		{ MTL::PixelFormatB5G6R5Unorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // B5G6R5
		{ MTL::PixelFormatB5G6R5Unorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $B, $G, $R, $A }, true  }, // R5G6B5
		{ MTL::PixelFormatABGR4Unorm,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $G, $B, $A, $R }, true  }, // BGRA4
		{ MTL::PixelFormatABGR4Unorm,            MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $A, $B, $G, $R }, true  }, // RGBA4
		{ MTL::PixelFormatBGR5A1Unorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // BGR5A1
		{ MTL::PixelFormatBGR5A1Unorm,           MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $B, $G, $R, $A }, true  }, // RGB5A1
		{ MTL::PixelFormatRGB10A2Unorm,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RGB10A2
		{ MTL::PixelFormatRG11B10Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, true  }, // RG11B10F
		{ MTL::PixelFormatInvalid,               MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // UnknownDepth
		{ MTL::PixelFormatDepth16Unorm,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D16
		{ MTL::PixelFormatDepth32Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D24
		{ MTL::PixelFormatDepth24Unorm_Stencil8, MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D24S8
		{ MTL::PixelFormatDepth32Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D32
		{ MTL::PixelFormatDepth32Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D16F
		{ MTL::PixelFormatDepth32Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D24F
		{ MTL::PixelFormatDepth32Float,          MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D32F
		{ MTL::PixelFormatStencil8,              MTL::PixelFormatInvalid,              MTL::ReadWriteTextureTierNone, { $R, $G, $B, $A }, false }, // D0S8
#undef $0
#undef $1
#undef $R
#undef $G
#undef $B
#undef $A
	};
	static_assert(TextureFormat::Count == BX_COUNTOF(s_textureFormat) );

BX_PRAGMA_DIAGNOSTIC_POP();

	// Reference(s):
	//
	// - Metal feature set tables
	//   https://web.archive.org/web/20230330111145/https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf
	//
	// - MTLPixelFormat pixel format capabilities
	//   https://developer.apple.com/documentation/metal/mtlpixelformat
	//
	struct TextureFormatCaps
	{
		TextureFormatCaps(MTL::Device* _device, bool _hasPacked16Formats)
		{
			m_ios      = BX_ENABLED(BX_PLATFORM_IOS) || BX_ENABLED(BX_PLATFORM_VISIONOS);
			m_osx      = BX_ENABLED(BX_PLATFORM_OSX);
			m_apple    = _device->supportsFamily(MTL::GPUFamilyApple1);
			m_apple3   = _device->supportsFamily(MTL::GPUFamilyApple3);
			m_apple7   = _device->supportsFamily(MTL::GPUFamilyApple7);
			m_mac2     = _device->supportsFamily(MTL::GPUFamilyMac2);
			m_bc       = _device->supportsBCTextureCompression();
			m_packed16 = _hasPacked16Formats;
			m_rwTier   = _device->readWriteTextureSupport();
		}

		uint32_t getCaps(TextureFormat::Enum _fmt) const
		{
			const TextureFormatInfo& tfi = s_textureFormat[_fmt];

			if (MTL::PixelFormatInvalid == tfi.m_fmt)
			{
				return BGFX_CAPS_FORMAT_TEXTURE_NONE;
			}

			bool supported   = false;
			bool framebuffer = false;
			bool multisample = false;
			bool storage     = false;
			bool supports3D  = false;

			switch (_fmt)
			{
			case TextureFormat::BC1:
			case TextureFormat::BC2:
			case TextureFormat::BC3:
			case TextureFormat::BC4:
			case TextureFormat::BC5:
			case TextureFormat::BC6H:
			case TextureFormat::BC7:
				supported = m_bc;
				break;

			case TextureFormat::ETC2:
			case TextureFormat::ETC2A:
			case TextureFormat::ETC2A1:
			case TextureFormat::EACR11:
			case TextureFormat::EACR11S:
			case TextureFormat::EACRG11:
			case TextureFormat::EACRG11S:
				supported = m_apple;
				break;

			case TextureFormat::PTC12:
			case TextureFormat::PTC14:
			case TextureFormat::PTC12A:
			case TextureFormat::PTC14A:
				// PVRTC is only available on iOS/tvOS/visionOS Apple GPUs.
				supported = m_apple && m_ios;
				break;

			case TextureFormat::ASTC4x4:
			case TextureFormat::ASTC5x4:
			case TextureFormat::ASTC5x5:
			case TextureFormat::ASTC6x5:
			case TextureFormat::ASTC6x6:
			case TextureFormat::ASTC8x5:
			case TextureFormat::ASTC8x6:
			case TextureFormat::ASTC8x8:
			case TextureFormat::ASTC10x5:
			case TextureFormat::ASTC10x6:
			case TextureFormat::ASTC10x8:
			case TextureFormat::ASTC10x10:
			case TextureFormat::ASTC12x10:
			case TextureFormat::ASTC12x12:
				supported = m_apple;
				break;

			case TextureFormat::A8:
				// A8Unorm is not color-renderable on any Metal GPU.
				supported  = true;
				supports3D = true;
				break;

			case TextureFormat::R8:
			case TextureFormat::RG8:
			case TextureFormat::RGBA8:
			case TextureFormat::BGRA8:
			case TextureFormat::R8S:
			case TextureFormat::RG8S:
			case TextureFormat::RGBA8S:
			case TextureFormat::R8I:
			case TextureFormat::R8U:
			case TextureFormat::RG8I:
			case TextureFormat::RG8U:
			case TextureFormat::RGBA8I:
			case TextureFormat::RGBA8U:
				supported   = true;
				framebuffer = true;
				multisample = true;
				storage     = true;
				supports3D  = true;
				break;

			case TextureFormat::R16:
			case TextureFormat::R16S:
			case TextureFormat::RG16:
			case TextureFormat::RG16S:
			case TextureFormat::RGBA16:
			case TextureFormat::RGBA16S:
				// Unorm/Snorm 16-bit formats: Apple GPUs and Mac2 only.
				supported   = m_apple || m_mac2;
				framebuffer = true;
				multisample = true;
				supports3D  = true;
				break;

			case TextureFormat::R16F:
			case TextureFormat::RG16F:
			case TextureFormat::RGBA16F:
			case TextureFormat::R16I:
			case TextureFormat::R16U:
			case TextureFormat::RG16I:
			case TextureFormat::RG16U:
			case TextureFormat::RGBA16I:
			case TextureFormat::RGBA16U:
				supported   = true;
				framebuffer = true;
				multisample = true;
				storage     = true;
				supports3D  = true;
				break;

			case TextureFormat::R32F:
			case TextureFormat::RG32F:
				// 32-bit float MSAA requires Mac2 or Apple7+ GPU family.
				supported   = true;
				framebuffer = true;
				multisample = m_mac2 || m_apple7;
				storage     = true;
				supports3D  = true;
				break;

			case TextureFormat::RGBA32F:
				// RGBA32Float MSAA requires Mac2.
				supported   = true;
				framebuffer = true;
				multisample = m_mac2;
				storage     = true;
				supports3D  = true;
				break;

			case TextureFormat::R32I:
			case TextureFormat::R32U:
			case TextureFormat::RG32I:
			case TextureFormat::RG32U:
			case TextureFormat::RGBA32I:
			case TextureFormat::RGBA32U:
				// Integer 32-bit formats do not support MSAA.
				supported   = true;
				framebuffer = true;
				storage     = true;
				supports3D  = true;
				break;

			case TextureFormat::RGB10A2:
			case TextureFormat::RG11B10F:
				supported   = true;
				framebuffer = true;
				multisample = true;
				supports3D  = true;
				break;

			case TextureFormat::RGB9E5F:
				// Not color-renderable on Mac (non-Apple) GPUs.
				supported   = true;
				framebuffer = m_apple;
				multisample = m_apple;
				supports3D  = true;
				break;

			case TextureFormat::B5G6R5:
			case TextureFormat::R5G6B5:
			case TextureFormat::BGRA4:
			case TextureFormat::RGBA4:
			case TextureFormat::BGR5A1:
			case TextureFormat::RGB5A1:
				// Packed 16-bit formats require macOS 11.0+ / iOS 8.0+.
				supported   = m_packed16;
				framebuffer = true;
				multisample = true;
				supports3D  = true;
				break;

			case TextureFormat::D16:
			case TextureFormat::D24:
			case TextureFormat::D24S8:
			case TextureFormat::D32:
			case TextureFormat::D16F:
			case TextureFormat::D24F:
			case TextureFormat::D32F:
			case TextureFormat::D0S8:
				supported   = true;
				framebuffer = true;
				multisample = true;
				break;

			default:
				break;
			}

			if (!supported)
			{
				return BGFX_CAPS_FORMAT_TEXTURE_NONE;
			}

			uint32_t caps = 0
				| BGFX_CAPS_FORMAT_TEXTURE_2D
				| BGFX_CAPS_FORMAT_TEXTURE_CUBE
				| BGFX_CAPS_FORMAT_TEXTURE_VERTEX
				| (supports3D ? BGFX_CAPS_FORMAT_TEXTURE_3D : 0)
				;

			if (MTL::PixelFormatInvalid != tfi.m_fmtSrgb)
			{
				caps |= 0
					| BGFX_CAPS_FORMAT_TEXTURE_2D_SRGB
					| BGFX_CAPS_FORMAT_TEXTURE_CUBE_SRGB
					| (supports3D ? BGFX_CAPS_FORMAT_TEXTURE_3D_SRGB : 0)
					;
			}

			if (framebuffer)
			{
				caps |= BGFX_CAPS_FORMAT_TEXTURE_FRAMEBUFFER;
			}

			if (multisample)
			{
				caps |= 0
					| BGFX_CAPS_FORMAT_TEXTURE_FRAMEBUFFER_MSAA
					| BGFX_CAPS_FORMAT_TEXTURE_MSAA
					;
			}

			if (true
			&&  storage
			&&  MTL::ReadWriteTextureTierNone != tfi.m_rwTier
			&&  tfi.m_rwTier <= m_rwTier
			   )
			{
				caps |= 0
					| BGFX_CAPS_FORMAT_TEXTURE_IMAGE_READ
					| BGFX_CAPS_FORMAT_TEXTURE_IMAGE_WRITE
					;
			}

			if (tfi.m_autoGetMipmap)
			{
				caps |= BGFX_CAPS_FORMAT_TEXTURE_MIP_AUTOGEN;
			}

			if (false
			||  TextureFormat::BGRA8   == _fmt
			||  TextureFormat::RGBA16F == _fmt
			   )
			{
				// CAMetalLayer accepts BGRA8Unorm(_sRGB) and RGBA16Float as drawable pixel formats.
				caps |= BGFX_CAPS_FORMAT_TEXTURE_BACKBUFFER;
			}

			return caps;
		}

		bool m_ios;
		bool m_osx;
		bool m_apple;
		bool m_apple3;
		bool m_apple7;
		bool m_mac2;
		bool m_bc;
		bool m_packed16;
		MTL::ReadWriteTextureTier m_rwTier;
	};

	int32_t s_msaa[] =
	{
		 1,
		 2,
		 4,
		 8,
		16,
	};

	static float s_shadingRate[] =
	{
		1.0f,
		0.75f,
		0.75f,
		0.5f,
		0.5f,
		0.5f,
		0.25f,
	};
	static_assert(ShadingRate::Count == BX_COUNTOF(s_shadingRate) );

	static UniformType::Enum convertMtlType(MTL::DataType _type)
	{
		switch (_type)
		{
		case MTL::DataTypeUInt:
		case MTL::DataTypeInt:
			return UniformType::Sampler;

		case MTL::DataTypeFloat:
		case MTL::DataTypeFloat2:
		case MTL::DataTypeFloat3:
		case MTL::DataTypeFloat4:
			return UniformType::Vec4;

		case MTL::DataTypeFloat3x3:
			return UniformType::Mat3;

		case MTL::DataTypeFloat4x4:
			return UniformType::Mat4;

		default:
			break;
		};

		BX_ASSERT(false, "Unrecognized Mtl Data type 0x%04x.", _type);
		return UniformType::End;
	}

#if BX_PLATFORM_OSX
	static uint32_t getEntryProperty(io_registry_entry_t _entry, CFStringRef _propertyName)
	{
		uint32_t result = 0;

		CFTypeRef typeRef = IORegistryEntrySearchCFProperty(
			  _entry
			, kIOServicePlane
			, _propertyName
			, kCFAllocatorDefault
			, kIORegistryIterateRecursively | kIORegistryIterateParents
			);

		if (NULL != typeRef)
		{
			const uint32_t* value = (const uint32_t*)(CFDataGetBytePtr( (CFDataRef)typeRef) );
			if (NULL != value)
			{
				result = *value;
			}

			CFRelease(typeRef);
		}

		return result;
	}
#endif // BX_PLATFORM_OSX

static const char* s_accessNames[] = {
	"Access::Read",
	"Access::Write",
	"Access::ReadWrite",
};
static_assert(BX_COUNTOF(s_accessNames) == Access::Count, "Invalid s_accessNames count");

#ifndef __IPHONE_OS_VERSION_MAX_ALLOWED
#	define __IPHONE_OS_VERSION_MAX_ALLOWED 0
#endif // __IPHONE_OS_VERSION_MAX_ALLOWED

#ifndef __MAC_OS_X_VERSION_MAX_ALLOWED
#	define __MAC_OS_X_VERSION_MAX_ALLOWED 0
#endif // __IPHONE_OS_VERSION_MAX_ALLOWED

#ifndef __VISION_OS_VERSION_MAX_ALLOWED
#	define __VISION_OS_VERSION_MAX_ALLOWED 0
#endif // __VISION_OS_VERSION_MAX_ALLOWED

#ifndef BX_XCODE_15
#	define BX_XCODE_15 (0                          \
	|| (__MAC_OS_X_VERSION_MAX_ALLOWED  >= 140000) \
	|| (__IPHONE_OS_VERSION_MAX_ALLOWED >= 170000) \
	)
#endif // BX_XCODE_15

#ifndef BX_XCODE_14
#   define BX_XCODE_14 (0                          \
	|| (__MAC_OS_X_VERSION_MAX_ALLOWED  >= 130000) \
	|| (__IPHONE_OS_VERSION_MAX_ALLOWED >= 160000) \
	)
#endif // BX_XCODE_14

#ifndef BX_XCODE_13
#	define BX_XCODE_13 (0                          \
	|| (__MAC_OS_X_VERSION_MAX_ALLOWED  >= 120000) \
	|| (__IPHONE_OS_VERSION_MAX_ALLOWED >= 150000) \
	)
#endif // BX_XCODE_13

#ifndef BX_XCODE_12
#	define BX_XCODE_12 (0 \
	|| (__MAC_OS_X_VERSION_MAX_ALLOWED  >= 110000) \
	|| (__IPHONE_OS_VERSION_MAX_ALLOWED >= 140000) \
	)
#endif // BX_XCODE_12

#if __VISION_OS_VERSION_MAX_ALLOWED >= 10000
#	define VISION_OS_MINIMUM visionOS 1.0,
#else
#	define VISION_OS_MINIMUM
#endif // __VISION_OS_VERSION_MAX_ALLOWED >= 10000

#define SHADER_FUNCTION_NAME "xlatMtlMain"
#define SHADER_UNIFORM_NAME  "_mtl_u"

	struct RendererContextMtl;
	static RendererContextMtl* s_renderMtl;

	struct RendererContextMtl : public RendererContextI
	{
		RendererContextMtl()
			: m_device(NULL)
			, m_uniformBuffer(NULL)
			, m_bufferIndex(0)
			, m_numWindows(0)
			, m_rtMsaa(false)
			, m_capture(NULL)
			, m_captureSize(0)
			, m_variableRateShadingSupported(false)
			, m_supportsDepthClipMode(false)
			, m_depthClamp(false)
			, m_screenshotTarget(NULL)
			, m_screenshotBlitRenderPipelineState(NULL)
			, m_commandBuffer(NULL)
			, m_blitCommandEncoder(NULL)
			, m_renderCommandEncoder(NULL)
			, m_computeCommandEncoder(NULL)
		{
			bx::memSet(&m_windows, 0xff, sizeof(m_windows) );
			bx::memSet(m_uniformBuffers, 0, sizeof(m_uniformBuffers) );
		}

		~RendererContextMtl()
		{
		}

		bool init(const Init& _init)
		{
			BX_TRACE("Init.");

#define CHECK_FEATURE_AVAILABLE(feature, ...)                                                \
	BX_MACRO_BLOCK_BEGIN                                                                     \
		if (__builtin_available(__VA_ARGS__) ) { feature = true; } else { feature = false; } \
		BX_TRACE("[MTL] OS feature %s: %d", (#feature) + 2, feature);                        \
	BX_MACRO_BLOCK_END

			CHECK_FEATURE_AVAILABLE(m_usesMTLBindings, macOS 13.0, iOS 16.0, tvOS 16.0, macCatalyst 16.0, VISION_OS_MINIMUM *);
			CHECK_FEATURE_AVAILABLE(m_hasCPUCacheModesAndStorageModes, iOS 9.0, macOS 10.11, macCatalyst 13.1, tvOS 9.0, VISION_OS_MINIMUM *);
			CHECK_FEATURE_AVAILABLE(m_hasSynchronizeResource, macOS 10.11, macCatalyst 13.0, *);
			CHECK_FEATURE_AVAILABLE(m_hasVSync, macOS 10.13, macCatalyst 13.1, *);
			CHECK_FEATURE_AVAILABLE(m_hasMaximumDrawableCount, iOS 11.2, macOS 10.13.2, macCatalyst 13.1, tvOS 11.2, VISION_OS_MINIMUM *);

			m_fbh = BGFX_INVALID_HANDLE;
			bx::memSet(m_uniforms, 0, sizeof(m_uniforms) );
			m_resolution = _init.resolution;

			m_device = (MTL::Device*)g_platformData.context;

			if (NULL == m_device)
			{
				m_device = MTL::CreateSystemDefaultDevice();
			}

			if (NULL == m_device)
			{
				BX_WARN(NULL != m_device, "Unable to create Metal device.");
				return false;
			}

			retain(m_device);

			if (m_device->supportsFamily(MTL::GPUFamilyApple4) )
			{
				g_caps.vendorId = BGFX_PCI_ID_APPLE;
				g_caps.deviceId = MTL::GPUFamilyApple4;

				static const MTL::GPUFamily s_appleFamily[] =
				{
					MTL::GPUFamilyApple10,
					MTL::GPUFamilyApple9,
					MTL::GPUFamilyApple8,
					MTL::GPUFamilyApple7,
					MTL::GPUFamilyApple6,
					MTL::GPUFamilyApple5,
				};

				for (uint32_t ii = 0; ii < BX_COUNTOF(s_appleFamily); ++ii)
				{
					if (m_device->supportsFamily(s_appleFamily[ii]) )
					{
						g_caps.deviceId = s_appleFamily[ii];
						break;
					}
				}
			}

#if BX_PLATFORM_OSX
			if (0 == g_caps.vendorId)
			{
				io_registry_entry_t entry;

				uint64_t registryId = m_device->registryID();

				if (0 != registryId)
				{
					entry = IOServiceGetMatchingService(mach_port_t(NULL), IORegistryEntryIDMatching(registryId) );

					if (0 != entry)
					{
						io_registry_entry_t parent;

						if (kIOReturnSuccess == IORegistryEntryGetParentEntry(entry, kIOServicePlane, &parent) )
						{
							g_caps.vendorId = getEntryProperty(parent, CFSTR("vendor-id") );
							g_caps.deviceId = getEntryProperty(parent, CFSTR("device-id") );

							IOObjectRelease(parent);
						}

						IOObjectRelease(entry);
					}
				}
			}
#endif // BX_PLATFORM_OSX

			m_variableRateShadingSupported = false; //m_device.supportsVariableRasterizationRate();

			m_supportsDepthClipMode = m_device->supportsFamily(MTL::GPUFamilyMac2)
				|| m_device->supportsFamily(MTL::GPUFamilyApple4);

			g_caps.numGPUs = 1;
			g_caps.gpu[0].vendorId = g_caps.vendorId;
			g_caps.gpu[0].deviceId = g_caps.deviceId;

			g_caps.supported |= (0
				| BGFX_CAPS_ALPHA_TO_COVERAGE
				| BGFX_CAPS_BLEND_INDEPENDENT
				| BGFX_CAPS_COMPUTE
				| BGFX_CAPS_FRAGMENT_DEPTH
				| BGFX_CAPS_INDEX32
				| BGFX_CAPS_INSTANCING
				| BGFX_CAPS_OCCLUSION_QUERY
				| BGFX_CAPS_SWAP_CHAIN
				| BGFX_CAPS_TEXTURE_2D_ARRAY
				| BGFX_CAPS_TEXTURE_3D
				| BGFX_CAPS_TEXTURE_BLIT
				| BGFX_CAPS_TEXTURE_EXTERNAL
				| BGFX_CAPS_TEXTURE_READ_BACK
				| BGFX_CAPS_VERTEX_ATTRIB_HALF
				| BGFX_CAPS_VERTEX_ATTRIB_UINT10
				| BGFX_CAPS_VERTEX_ID
				);

			g_caps.supported |= (m_device->supportsFamily(MTL::GPUFamilyApple7) || m_device->supportsFamily(MTL::GPUFamilyMac2) )
				? BGFX_CAPS_PRIMITIVE_ID
				: 0
				;

			// Reference(s):
			// - Metal feature set tables
			//   https://web.archive.org/web/20230330111145/https://developer.apple.com/metal/Metal-Feature-Set-Tables.pdf
			g_caps.limits.maxTextureSize = (m_device->supportsFamily(MTL::GPUFamilyApple3) || m_device->supportsFamily(MTL::GPUFamilyMac2) ) ? 16384 : 8192;
			g_caps.limits.maxFBAttachments = 8;
			g_caps.supported |= (m_device->supportsFamily(MTL::GPUFamilyApple3) || m_device->supportsFamily(MTL::GPUFamilyMac2) )
				? BGFX_CAPS_DRAW_INDIRECT
				| BGFX_CAPS_TEXTURE_CUBE_ARRAY
				| BGFX_CAPS_TEXTURE_COMPARE_ALL
				: 0
				;

			g_caps.limits.maxTextureLayers = 2048;
			g_caps.limits.maxVertexStreams = BGFX_CONFIG_MAX_VERTEX_STREAMS;
			// Maximum number of entries in the buffer argument table, per graphics or compute function are 31.
			// It is decremented by 1 because 1 entry is used for uniforms.
			g_caps.limits.maxComputeBindings = bx::min(30, BGFX_MAX_COMPUTE_BINDINGS);

			g_caps.supported |= m_variableRateShadingSupported
				? BGFX_CAPS_VARIABLE_RATE_SHADING
				: 0
				;

			CHECK_FEATURE_AVAILABLE(
				  m_hasPixelFormatDepth32Float_Stencil8
				, iOS 9.0
				, macOS 10.11
				, macCatalyst 13.1
				, tvOS 9.0
				, VISION_OS_MINIMUM *
				);
			CHECK_FEATURE_AVAILABLE(
				  m_hasStoreActionStoreAndMultisampleResolve
				, iOS 10.0
				, macOS 10.12
				, macCatalyst 13.1
				, tvOS 10.0
				, VISION_OS_MINIMUM *
				);

			// R8Unorm_sRGB / RG8Unorm_sRGB are unsupported on Mac (non-Apple) GPUs.
			if (!m_device->supportsFamily(MTL::GPUFamilyApple1) )
			{
				s_textureFormat[TextureFormat::R8 ].m_fmtSrgb = MTL::PixelFormatInvalid;
				s_textureFormat[TextureFormat::RG8].m_fmtSrgb = MTL::PixelFormatInvalid;
			}

			bool hasPacked16Formats;
			CHECK_FEATURE_AVAILABLE(
				  hasPacked16Formats
				, iOS 8.0
				, macOS 11.0
				, macCatalyst 14.0
				, tvOS 9.0
				, VISION_OS_MINIMUM *
				);

			if (g_caps.vendorId == BGFX_PCI_ID_AMD)
			{
				hasPacked16Formats = false;
			}

			if (!hasPacked16Formats)
			{
				s_textureFormat[bgfx::TextureFormat::R5G6B5].m_fmt = MTL::PixelFormatInvalid;
				s_textureFormat[bgfx::TextureFormat::B5G6R5].m_fmt = MTL::PixelFormatInvalid;
				s_textureFormat[bgfx::TextureFormat::BGRA4 ].m_fmt = MTL::PixelFormatInvalid;
				s_textureFormat[bgfx::TextureFormat::RGBA4 ].m_fmt = MTL::PixelFormatInvalid;
			}

			const MTL::ReadWriteTextureTier rwTier = m_device->readWriteTextureSupport();
			g_caps.supported |= rwTier != MTL::ReadWriteTextureTierNone
				? BGFX_CAPS_IMAGE_RW
				: 0
				;

			bool hasD16Format;
			CHECK_FEATURE_AVAILABLE(
				  hasD16Format
				, iOS 13.0
				, macOS 10.12
				, macCatalyst 13.1
				, tvOS 13.0
				, VISION_OS_MINIMUM *
				);

			if (!hasD16Format)
			{
				s_textureFormat[TextureFormat::D16].m_fmt = MTL::PixelFormatDepth32Float;
			}

			s_textureFormat[TextureFormat::D24S8].m_fmt = BX_ENABLED(BX_PLATFORM_OSX) && m_device->isDepth24Stencil8PixelFormatSupported()
				? MTL::PixelFormatDepth24Unorm_Stencil8
				: MTL::PixelFormatDepth32Float_Stencil8
				;

			TextureFormatCaps textureFormatCaps(m_device, hasPacked16Formats);

			for (uint32_t ii = 0; ii < TextureFormat::Count; ++ii)
			{
				g_caps.formats[ii] = textureFormatCaps.getCaps(TextureFormat::Enum(ii) );
			}

			for (uint32_t ii = 0; ii < TextureFormat::Count; ++ii)
			{
				if (BGFX_CAPS_FORMAT_TEXTURE_NONE == g_caps.formats[ii])
				{
					s_textureFormat[ii].m_fmt     = MTL::PixelFormatInvalid;
					s_textureFormat[ii].m_fmtSrgb = MTL::PixelFormatInvalid;
				}
			}

			for (uint32_t ii = 1, last = 0; ii < BX_COUNTOF(s_msaa); ++ii)
			{
				const int32_t sampleCount = 1<<ii;
				if (m_device->supportsTextureSampleCount(sampleCount) )
				{
					s_msaa[ii] = sampleCount;
					last = ii;
				}
				else
				{
					s_msaa[ii] = s_msaa[last];
				}
			}

			// Init reserved part of view name.
			for (uint32_t ii = 0; ii < BGFX_CONFIG_MAX_VIEWS; ++ii)
			{
				bx::snprintf(s_viewName[ii], BGFX_CONFIG_MAX_VIEW_NAME_RESERVED+1, "%3d   ", ii);
			}

			m_renderPipelineDescriptor   = newRenderPipelineDescriptor();
			m_depthStencilDescriptor     = newDepthStencilDescriptor();
			m_frontFaceStencilDescriptor = newStencilDescriptor();
			m_backFaceStencilDescriptor  = newStencilDescriptor();
			m_vertexDescriptor           = newVertexDescriptor();
			m_samplerDescriptor          = newSamplerDescriptor();

			if (NULL == g_platformData.nwh)
			{
				BX_TRACE("Headless.");
			}
			else
			{
				m_mainFrameBuffer.create(
					  0
					, g_platformData.nwh
					, m_resolution.width
					, m_resolution.height
					, m_resolution.formatColor
					, m_resolution.formatDepthStencil
					);
				m_textVideoMem.resize(false, m_resolution.width, m_resolution.height);
				m_textVideoMem.clear();

				m_numWindows = 1;

				if (NULL == m_mainFrameBuffer.m_swapChain->m_metalLayer)
				{
					MTL_RELEASE(m_device, 0);
					return false;
				}
			}

			m_cmd.init(m_device, _init.resolution.maxFrameLatency);
			BGFX_FATAL(NULL != m_cmd.m_commandQueue, Fatal::UnableToInitialize, "Unable to create Metal device.");

			for (uint8_t ii = 0; ii < BGFX_CONFIG_MAX_FRAME_LATENCY; ++ii)
			{
				m_uniformBuffers[ii] = m_device->newBuffer(UNIFORM_BUFFER_SIZE, MTL::ResourceCPUCacheModeDefaultCache);
			}

			m_uniformBufferVertexOffset   = 0;
			m_uniformBufferFragmentOffset = 0;

			const char* vshSource =
				"using namespace metal;\n"
				"struct xlatMtlShaderOutput { float4 gl_Position [[position]]; float2 v_texcoord0; }; \n"
				"vertex xlatMtlShaderOutput xlatMtlMain (uint v_id [[ vertex_id ]]) \n"
				"{\n"
				"   xlatMtlShaderOutput _mtl_o;\n"
				"   if (v_id==0) { _mtl_o.gl_Position = float4(-1.0,-1.0,0.0,1.0); _mtl_o.v_texcoord0 = float2(0.0,1.0); } \n"
				"   else if (v_id==1) { _mtl_o.gl_Position = float4(3.0,-1.0,0.0,1.0); _mtl_o.v_texcoord0 = float2(2.0,1.0); } \n"
				"   else { _mtl_o.gl_Position = float4(-1.0,3.0,0.0,1.0); _mtl_o.v_texcoord0 = float2(0.0,-1.0); }\n"
				"   return _mtl_o;\n"
				"}\n"
				;

			 const char* fshSource =
				"using namespace metal;\n"
				"struct xlatMtlShaderInput { float2 v_texcoord0; };\n"
				"fragment half4 xlatMtlMain (xlatMtlShaderInput _mtl_i[[stage_in]], texture2d<float> s_texColor [[texture(0)]], sampler _mtlsmp_s_texColor [[sampler(0)]] )\n"
				"{\n"
				"   return half4(s_texColor.sample(_mtlsmp_s_texColor, _mtl_i.v_texcoord0) );\n"
				"}\n"
				;

			MTL::Library* lib = newLibraryWithSource(m_device, vshSource);
			if (NULL != lib)
			{
				m_screenshotBlitProgramVsh.m_function = lib->newFunction(nsstr(SHADER_FUNCTION_NAME) );
				MTL_RELEASE_W(lib, 0);
			}

			lib = newLibraryWithSource(m_device, fshSource);
			if (NULL != lib)
			{
				m_screenshotBlitProgramFsh.m_function = lib->newFunction(nsstr(SHADER_FUNCTION_NAME) );
				MTL_RELEASE_W(lib, 0);
			}

			m_screenshotBlitProgram.create(&m_screenshotBlitProgramVsh, &m_screenshotBlitProgramFsh);

			reset(m_renderPipelineDescriptor);
			m_renderPipelineDescriptor->colorAttachments()->object(0)->setPixelFormat(getSwapChainPixelFormat(m_mainFrameBuffer.m_swapChain) );

			m_renderPipelineDescriptor->setVertexFunction(m_screenshotBlitProgram.m_vsh->m_function);
			m_renderPipelineDescriptor->setFragmentFunction(m_screenshotBlitProgram.m_fsh->m_function);
			m_screenshotBlitRenderPipelineState = newRenderPipelineStateWithDescriptor(m_device, m_renderPipelineDescriptor);

			m_occlusionQuery.preReset();
			m_gpuTimer.init();

			g_internalData.context = m_device;

			return true;
		}

		void shutdown()
		{
			{
				NS::AutoreleasePool* pool = NS::AutoreleasePool::alloc()->init();

				m_gpuTimer.shutdown();
				m_cmd.kick(false, true);

				pool->release();
			}

			{
				NS::AutoreleasePool* pool = NS::AutoreleasePool::alloc()->init();

				m_pipelineStateCache.invalidate();
				m_pipelineProgram.clear();

				m_depthStencilStateCache.invalidate();
				m_samplerStateCache.invalidate();

				for (uint32_t ii = 0; ii < BX_COUNTOF(m_shaders); ++ii)
				{
					m_shaders[ii].destroy();
				}

				for (uint32_t ii = 0; ii < BX_COUNTOF(m_textures); ++ii)
				{
					m_textures[ii].destroy();
				}

				m_screenshotBlitProgramVsh.destroy();
				m_screenshotBlitProgramFsh.destroy();
				m_screenshotBlitProgram.destroy();
				MTL_RELEASE(m_screenshotBlitRenderPipelineState, 0);

				captureFinish();

				MTL_RELEASE(m_depthStencilDescriptor, 0);
				MTL_RELEASE(m_frontFaceStencilDescriptor, 0);
				MTL_RELEASE(m_backFaceStencilDescriptor, 0);
				MTL_RELEASE(m_renderPipelineDescriptor, 0);
				MTL_RELEASE(m_vertexDescriptor, 0);
				MTL_RELEASE(m_samplerDescriptor, 0);

				m_occlusionQuery.postReset();
				m_mainFrameBuffer.destroy();

				m_cmd.shutdown();

				for (uint8_t ii = 0; ii < BGFX_CONFIG_MAX_FRAME_LATENCY; ++ii)
				{
					MTL_RELEASE_W(m_uniformBuffers[ii], 0);
				}

				MTL_RELEASE_W(m_device, 0);

				pool->release();
			}
		}

		RendererType::Enum getRendererType() const override
		{
			return RendererType::Metal;
		}

		const char* getRendererName() const override
		{
			return BGFX_RENDERER_METAL_NAME;
		}

		void createIndexBuffer(IndexBufferHandle _handle, const Memory* _mem, uint16_t _flags) override
		{
			m_indexBuffers[_handle.idx].create(_mem->size, _mem->data, _flags);
		}

		void destroyIndexBuffer(IndexBufferHandle _handle) override
		{
			m_indexBuffers[_handle.idx].destroy();
		}

		void createVertexLayout(VertexLayoutHandle _handle, const VertexLayout& _layout) override
		{
			VertexLayout& layout = m_vertexLayouts[_handle.idx];
			bx::memCopy(&layout, &_layout, sizeof(VertexLayout) );
			dump(layout);
		}

		void destroyVertexLayout(VertexLayoutHandle /*_handle*/) override
		{
		}

		void createVertexBuffer(VertexBufferHandle _handle, const Memory* _mem, VertexLayoutHandle _layoutHandle, uint16_t _flags) override
		{
			m_vertexBuffers[_handle.idx].create(_mem->size, _mem->data, _layoutHandle, _flags);
		}

		void destroyVertexBuffer(VertexBufferHandle _handle) override
		{
			m_vertexBuffers[_handle.idx].destroy();
		}

		void createDynamicIndexBuffer(IndexBufferHandle _handle, uint32_t _size, uint16_t _flags) override
		{
			m_indexBuffers[_handle.idx].create(_size, NULL, _flags);
		}

		void updateDynamicIndexBuffer(IndexBufferHandle _handle, uint32_t _offset, uint32_t _size, const Memory* _mem) override
		{
			m_indexBuffers[_handle.idx].update(_offset, bx::min(_size, _mem->size), _mem->data);
		}

		void destroyDynamicIndexBuffer(IndexBufferHandle _handle) override
		{
			m_indexBuffers[_handle.idx].destroy();
		}

		void createDynamicVertexBuffer(VertexBufferHandle _handle, uint32_t _size, uint16_t _flags) override
		{
			VertexLayoutHandle layoutHandle = BGFX_INVALID_HANDLE;
			m_vertexBuffers[_handle.idx].create(_size, NULL, layoutHandle, _flags);
		}

		void updateDynamicVertexBuffer(VertexBufferHandle _handle, uint32_t _offset, uint32_t _size, const Memory* _mem) override
		{
			m_vertexBuffers[_handle.idx].update(_offset, bx::min(_size, _mem->size), _mem->data);
		}

		void destroyDynamicVertexBuffer(VertexBufferHandle _handle) override
		{
			m_vertexBuffers[_handle.idx].destroy();
		}

		void createShader(ShaderHandle _handle, const Memory* _mem) override
		{
			m_shaders[_handle.idx].create(_mem);
		}

		void destroyShader(ShaderHandle _handle) override
		{
			m_shaders[_handle.idx].destroy();
		}

		void createProgram(ProgramHandle _handle, ShaderHandle _vsh, ShaderHandle _fsh) override
		{
			m_program[_handle.idx].create(&m_shaders[_vsh.idx], isValid(_fsh) ? &m_shaders[_fsh.idx] : NULL);
		}

		void destroyProgram(ProgramHandle _handle) override
		{
			for (PipelineProgramArray::iterator it = m_pipelineProgram.begin(); it != m_pipelineProgram.end();)
			{
				if (it->program.idx == _handle.idx)
				{
					m_pipelineStateCache.invalidate(it->key);
					it = m_pipelineProgram.erase(it);
				}
				else
				{
					++it;
				}
			}

			m_program[_handle.idx].destroy();
		}

		void* createTexture(TextureHandle _handle, const Memory* _mem, uint64_t _flags, uint8_t _skip, uint64_t _external) override
		{
			m_textures[_handle.idx].create(_mem, _flags, _skip, _external);
			return NULL;
		}

		void updateTexture(TextureHandle _handle, uint8_t _side, uint8_t _mip, const Rect& _rect, uint16_t _z, uint16_t _depth, uint16_t _pitch, const Memory* _mem) override
		{
			m_textures[_handle.idx].update(_side, _mip, _rect, _z, _depth, _pitch, _mem);
		}

		static MTL::PixelFormat getSwapChainPixelFormat(SwapChainMtl* _swapChain)
		{
			return NULL != _swapChain
				? _swapChain->m_metalLayer->pixelFormat()
				: MTL::PixelFormatInvalid
				;
		}

		void readTexture(TextureHandle _handle, void* _data, uint8_t _mip) override
		{
			const TextureMtl& texture = m_textures[_handle.idx];

#if BX_PLATFORM_OSX
			MTL::BlitCommandEncoder* bce = s_renderMtl->getBlitCommandEncoder();
			bce->synchronizeTexture(texture.m_ptr, 0, _mip);
			endEncoding();
#endif  // BX_PLATFORM_OSX

			m_cmd.kick(false, true);
			m_commandBuffer = m_cmd.alloc();

			BX_ASSERT(_mip<texture.m_numMips,"Invalid mip: %d num mips:",_mip,texture.m_numMips);

			const uint32_t srcWidth  = bx::max(1, texture.m_ptr->width()  >> _mip);
			const uint32_t srcHeight = bx::max(1, texture.m_ptr->height() >> _mip);
			const uint8_t  bpp       = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(texture.m_textureFormat) );

			MTL::Region region(0, 0, 0, srcWidth, srcHeight, 1);

			texture.m_ptr->getBytes(_data, srcWidth*bpp/8, 0, region, _mip, 0);
		}

		void resizeTexture(TextureHandle _handle, uint16_t _width, uint16_t _height, uint8_t _numMips, uint16_t _numLayers) override
		{
			TextureMtl& texture = m_textures[_handle.idx];

			uint32_t size = sizeof(uint32_t) + sizeof(TextureCreate);
			const Memory* mem = alloc(size);

			bx::StaticMemoryBlockWriter writer(mem->data, mem->size);
			bx::write(&writer, kChunkMagicTex, bx::ErrorAssert{});

			TextureCreate tc;
			tc.m_width     = _width;
			tc.m_height    = _height;
			tc.m_depth     = 0;
			tc.m_numLayers = _numLayers;
			tc.m_numMips   = _numMips;
			tc.m_format    = TextureFormat::Enum(texture.m_requestedFormat);
			tc.m_cubeMap   = false;
			tc.m_mem       = NULL;
			bx::write(&writer, tc, bx::ErrorAssert{});

			texture.destroy();
			texture.create(mem, texture.m_flags, 0, 0);

			release(mem);
		}

		void overrideInternal(TextureHandle _handle, uintptr_t _ptr, uint16_t /*_layerIndex*/) override
		{
			m_textures[_handle.idx].overrideInternal(_ptr);
		}

		uintptr_t getInternal(TextureHandle _handle) override
		{
			return uintptr_t(m_textures[_handle.idx].m_ptr);
		}

		void destroyTexture(TextureHandle _handle) override
		{
			m_textures[_handle.idx].destroy();
		}

		void createFrameBuffer(FrameBufferHandle _handle, uint8_t _num, const Attachment* _attachment) override
		{
			m_frameBuffers[_handle.idx].create(_num, _attachment);
		}

		void createFrameBuffer(FrameBufferHandle _handle, void* _nwh, uint32_t _width, uint32_t _height, TextureFormat::Enum _format, TextureFormat::Enum _depthFormat) override
		{
			for (uint32_t ii = 0, num = m_numWindows; ii < num; ++ii)
			{
				FrameBufferHandle handle = m_windows[ii];
				if (isValid(handle)
				&&  m_frameBuffers[handle.idx].m_nwh == _nwh)
				{
					destroyFrameBuffer(handle);
				}
			}

			uint16_t denseIdx   = m_numWindows++;
			m_windows[denseIdx] = _handle;

			FrameBufferMtl& fb = m_frameBuffers[_handle.idx];
			fb.create(denseIdx, _nwh, _width, _height, _format, _depthFormat);
		}

		void destroyFrameBuffer(FrameBufferHandle _handle) override
		{
			uint16_t denseIdx = m_frameBuffers[_handle.idx].destroy();

			if (UINT16_MAX != denseIdx)
			{
				--m_numWindows;

				if (m_numWindows > 1)
				{
					FrameBufferHandle handle = m_windows[m_numWindows];
					m_windows[m_numWindows]  = {kInvalidHandle};

					if (m_numWindows != denseIdx)
					{
						m_windows[denseIdx] = handle;
						m_frameBuffers[handle.idx].m_denseIdx = denseIdx;
					}
				}
			}
		}

		void createUniform(UniformHandle _handle, UniformType::Enum _type, uint16_t _num, const char* _name) override
		{
			if (NULL != m_uniforms[_handle.idx])
			{
				bx::free(g_allocator, m_uniforms[_handle.idx]);
			}

			const uint32_t size = bx::alignUp(g_uniformTypeSize[_type]*_num, 16);
			void* data = bx::alloc(g_allocator, size);
			bx::memSet(data, 0, size);
			m_uniforms[_handle.idx] = data;
			m_uniformReg.add(_handle, _name);
		}

		void destroyUniform(UniformHandle _handle) override
		{
			bx::free(g_allocator, m_uniforms[_handle.idx]);
			m_uniforms[_handle.idx] = NULL;
			m_uniformReg.remove(_handle);
		}

		void requestScreenShot(FrameBufferHandle _handle, const char* _filePath) override
		{
			BX_UNUSED(_handle);

			if (NULL == m_screenshotTarget)
			{
				return;
			}

#if BX_PLATFORM_OSX
			m_blitCommandEncoder = getBlitCommandEncoder();
			m_blitCommandEncoder->synchronizeResource(m_screenshotTarget);
			m_blitCommandEncoder->endEncoding();
			m_blitCommandEncoder = NULL;
#endif  // BX_PLATFORM_OSX

			m_cmd.kick(false, true);
			m_commandBuffer = 0;

			const uint32_t width  = m_screenshotTarget->width();
			const uint32_t height = m_screenshotTarget->height();
			const uint8_t  bpp    = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(m_resolution.formatColor) );
			const uint32_t pitch  = width * bpp / 8;
			const uint32_t size   = height*pitch;
			uint8_t* data   = (uint8_t*)bx::alloc(g_allocator, size);

			MTL::Region region(0, 0, 0, width, height, 1);

			m_screenshotTarget->getBytes(data, pitch, 0, region, 0, 0);

			g_callback->screenShot(
				  _filePath
				, m_screenshotTarget->width()
				, m_screenshotTarget->height()
				, pitch
				, m_resolution.formatColor
				, data
				, size
				, false
				);

			bx::free(g_allocator, data);

			m_commandBuffer = m_cmd.alloc();
		}

		void updateViewName(ViewId _id, const char* _name) override
		{
			bx::strCopy(
				  &s_viewName[_id][BGFX_CONFIG_MAX_VIEW_NAME_RESERVED]
				, BX_COUNTOF(s_viewName[0])-BGFX_CONFIG_MAX_VIEW_NAME_RESERVED
				, _name
				);
		}

		void updateUniform(uint16_t _loc, const void* _data, uint32_t _size) override
		{
			bx::memCopy(m_uniforms[_loc], _data, _size);
		}

		void invalidateOcclusionQuery(OcclusionQueryHandle _handle) override
		{
			m_occlusionQuery.invalidate(_handle);
		}

		void setMarker(const char* _marker, uint16_t _len) override
		{
			BX_UNUSED(_len);

			if (BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
			{
				m_renderCommandEncoder->insertDebugSignpost(nsstr(_marker) );
			}
		}

		virtual void setName(Handle _handle, const char* _name, uint16_t _len) override
		{
			BX_UNUSED(_len);

			switch (_handle.type)
			{
			case Handle::IndexBuffer:
				m_indexBuffers[_handle.idx].m_ptr->setLabel(nsstr(_name) );
				break;

			case Handle::Shader:
				m_shaders[_handle.idx].m_function->setLabel(nsstr(_name) );
				break;

			case Handle::Texture:
				m_textures[_handle.idx].m_ptr->setLabel(nsstr(_name) );
				break;

			case Handle::VertexBuffer:
				m_vertexBuffers[_handle.idx].m_ptr->setLabel(nsstr(_name) );
				break;

			default:
				BX_ASSERT(false, "Invalid handle type?! %d", _handle.type);
				break;
			}
		}

		void submitBlit(BlitState& _bs, uint16_t _view);

		void submitUniformCache(UniformCacheState& _ucs, uint16_t _view);

		void submit(Frame* _render, const ClearQuad& _clearQuad, const MipGen& _mipGen, TextVideoMemBlitter& _textVideoMemBlitter) override;

		void dbgTextRenderBegin(TextVideoMemBlitter& /*_blitter*/) override
		{
		}

		void dbgTextRender(TextVideoMemBlitter& _blitter, uint32_t _numIndices) override
		{
			const uint32_t numVertices = _numIndices*4/6;
			if (0 < numVertices)
			{
				m_indexBuffers[_blitter.m_ib->handle.idx].update(
					  0
					, bx::strideAlign(_numIndices*2, 4)
					, _blitter.m_ib->data
					, true
					);
				m_vertexBuffers[_blitter.m_vb->handle.idx].update(
					  0
					, numVertices*_blitter.m_layout.m_stride
					, _blitter.m_vb->data
					, true
					);

				endEncoding();

				const uint32_t width  = m_resolution.width;
				const uint32_t height = m_resolution.height;

				FrameBufferHandle fbh = BGFX_INVALID_HANDLE;

				MTL::RenderPassDescriptor* renderPassDescriptor = newRenderPassDescriptor();

				setFrameBuffer(renderPassDescriptor, fbh);

				renderPassDescriptor->colorAttachments()->object(0)->setLoadAction(MTL::LoadActionLoad);
				renderPassDescriptor->colorAttachments()->object(0)->setStoreAction(
					NULL != renderPassDescriptor->colorAttachments()->object(0)->resolveTexture()
					? MTL::StoreActionMultisampleResolve
					: MTL::StoreActionStore
					);

				MTL::RenderCommandEncoder* rce = m_commandBuffer->renderCommandEncoder(renderPassDescriptor);
				m_renderCommandEncoder = rce;
				m_renderCommandEncoderFrameBufferHandle = fbh;
				MTL_RELEASE(renderPassDescriptor, 0);

				if (m_depthClamp)
				{
					rce->setDepthClipMode(MTL::DepthClipModeClamp);
				}

				{
					MTL::Viewport viewport = { 0.0f, 0.0f, (float)width, (float)height, 0.0f, 1.0f };
					rce->setViewport(viewport);

					MTL::ScissorRect rc = { 0, 0, width, height };
					rce->setScissorRect(rc);
				}

				rce->setCullMode( (MTL::CullMode)MTL::CullModeNone);

				uint64_t state = 0
					| BGFX_STATE_WRITE_RGB
					| BGFX_STATE_WRITE_A
					| BGFX_STATE_DEPTH_TEST_ALWAYS
					;

				setDepthStencilState(state);

				PipelineStateMtl* pso = getPipelineState(
					  state
					, 0
					, fbh
					, _blitter.m_vb->layoutHandle
					, _blitter.m_program
					, 0
					);
				rce->setRenderPipelineState(pso->m_rps);

				const uint32_t vertexUniformBufferSize   = pso->m_vshConstantBufferSize;
				const uint32_t fragmentUniformBufferSize = pso->m_fshConstantBufferSize;

				if (vertexUniformBufferSize)
				{
					m_uniformBufferVertexOffset = bx::alignUp(
						  m_uniformBufferVertexOffset
						, pso->m_vshConstantBufferAlignment
						);
					rce->setVertexBuffer(m_uniformBuffer, m_uniformBufferVertexOffset, 0);
				}

				m_uniformBufferFragmentOffset = m_uniformBufferVertexOffset + vertexUniformBufferSize;

				if (0 != fragmentUniformBufferSize)
				{
					m_uniformBufferFragmentOffset = bx::alignUp(
						  m_uniformBufferFragmentOffset
						, pso->m_fshConstantBufferAlignment
						);
					rce->setFragmentBuffer(m_uniformBuffer, m_uniformBufferFragmentOffset, 0);
				}

				float proj[16];
				bx::mtxOrtho(proj, 0.0f, (float)width, (float)height, 0.0f, 0.0f, 1000.0f, 0.0f, false);

				PredefinedUniform& predefined = pso->m_predefined[0];
				uint8_t flags = predefined.m_type;
				setShaderUniform(flags, predefined.m_loc, proj, 4);

				m_textures[_blitter.m_texture.idx].commit(0, false, true);

				VertexBufferMtl& vb = m_vertexBuffers[_blitter.m_vb->handle.idx];
				m_renderCommandEncoder->setVertexBuffer(vb.m_ptr, 0, 1);

				m_renderCommandEncoder->drawIndexedPrimitives(
					  MTL::PrimitiveTypeTriangle
					, _numIndices
					, (MTL::IndexType)MTL::IndexTypeUInt16
					, m_indexBuffers[_blitter.m_ib->handle.idx].m_ptr
					, 0
					, 1
					);
			}
		}

		void dbgTextRenderEnd(TextVideoMemBlitter& /*_blitter*/) override
		{
		}

		bool isDeviceRemoved() override
		{
			return false;
		}

		void flip() override
		{
			bool needPresent = false;
			for (uint32_t ii = 0, num = m_numWindows; ii < num; ++ii)
			{
				FrameBufferMtl& frameBuffer = ii == 0 ? m_mainFrameBuffer : m_frameBuffers[m_windows[ii].idx];
				if (NULL != frameBuffer.m_swapChain
				&&  frameBuffer.m_swapChain->m_drawableTexture)
				{
					needPresent = true;
					break;
				}
			}

			if (!needPresent)
			{
				return;
			}

			MTL::CommandBuffer* presentCommandBuffer = m_cmd.alloc();

			for (uint32_t ii = 0, num = m_numWindows; ii < num; ++ii)
			{
				FrameBufferMtl& frameBuffer = ii == 0 ? m_mainFrameBuffer : m_frameBuffers[m_windows[ii].idx];

				if (NULL != frameBuffer.m_swapChain
				&&  frameBuffer.m_swapChain->m_drawableTexture)
				{
					MTL_RELEASE_I(frameBuffer.m_swapChain->m_drawableTexture);

					if (NULL != frameBuffer.m_swapChain->m_drawable)
					{
						presentCommandBuffer->presentDrawable( (MTL::Drawable*)frameBuffer.m_swapChain->m_drawable);
						MTL_RELEASE_I(frameBuffer.m_swapChain->m_drawable);
					}
				}
			}

			m_cmd.kick(false, false);
		}

		void updateResolution(const Resolution& _resolution)
		{
			SwapChainMtl* swapChain = m_mainFrameBuffer.m_swapChain;

			if (NULL != swapChain)
			{
				swapChain->m_maxAnisotropy = !!(_resolution.reset & BGFX_RESET_MAXANISOTROPY)
					? 16
					: 1
					;
			}

			m_depthClamp = m_supportsDepthClipMode
				&& !!(_resolution.reset & BGFX_RESET_DEPTH_CLAMP);

			uint32_t maskFlags = ~(0
				| BGFX_RESET_MAXANISOTROPY
				| BGFX_RESET_DEPTH_CLAMP
				| BGFX_RESET_SUSPEND
				);

#if BX_PLATFORM_OSX
#	if __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
			if (m_hasVSync
			&& !!((_resolution.reset ^ m_resolution.reset) & BGFX_RESET_VSYNC) )
			{
				m_resolution.reset = 0
					| (m_resolution.reset & ~BGFX_RESET_VSYNC)
					| ( _resolution.reset &  BGFX_RESET_VSYNC)
					;

				const bool displaySync = !!(m_resolution.reset & BGFX_RESET_VSYNC);

				for (uint32_t ii = 0, num = m_numWindows; ii < num; ++ii)
				{
					FrameBufferMtl& fb = 0 == ii
						? m_mainFrameBuffer
						: m_frameBuffers[m_windows[ii].idx]
						;

					if (NULL != fb.m_swapChain
					&&  NULL != fb.m_swapChain->m_metalLayer)
					{
						fb.m_swapChain->m_metalLayer->setDisplaySyncEnabled(displaySync);
					}
				}

				maskFlags &= ~BGFX_RESET_VSYNC;
			}
#	endif // __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
#endif // BX_PLATFORM_OSX

			if (m_resolution.width            !=  _resolution.width
			||  m_resolution.height           !=  _resolution.height
			|| (m_resolution.reset&maskFlags) != (_resolution.reset&maskFlags) )
			{
				m_resolution = _resolution;

				const MTL::PixelFormat prevPixelFormat = getSwapChainPixelFormat(swapChain);

				if (NULL != swapChain)
				{
					if (m_resolution.reset & BGFX_RESET_INTERNAL_FORCE
					&&  swapChain->m_nwh != g_platformData.nwh)
					{
						swapChain->init(g_platformData.nwh);
					}

					m_mainFrameBuffer.resizeSwapChain(_resolution.width, _resolution.height);
				}

				m_resolution.reset &= ~BGFX_RESET_INTERNAL_FORCE;

				for (uint32_t ii = 0; ii < BX_COUNTOF(m_frameBuffers); ++ii)
				{
					m_frameBuffers[ii].postReset();
				}

				updateCapture();

				m_textVideoMem.resize(false, _resolution.width, _resolution.height);
				m_textVideoMem.clear();

				const MTL::PixelFormat pixelFormat = getSwapChainPixelFormat(swapChain);

				if (prevPixelFormat != pixelFormat)
				{
					MTL_RELEASE_I(m_screenshotBlitRenderPipelineState);
					reset(m_renderPipelineDescriptor);

					m_renderPipelineDescriptor->colorAttachments()->object(0)->setPixelFormat(pixelFormat);
					m_renderPipelineDescriptor->setVertexFunction(m_screenshotBlitProgram.m_vsh->m_function);
					m_renderPipelineDescriptor->setFragmentFunction(m_screenshotBlitProgram.m_fsh->m_function);
					m_screenshotBlitRenderPipelineState = newRenderPipelineStateWithDescriptor(m_device, m_renderPipelineDescriptor);
				}
			}
		}

		void invalidateCompute()
		{
			if (m_computeCommandEncoder)
			{
				m_computeCommandEncoder->endEncoding();
				m_computeCommandEncoder = NULL;
			}
		}

		void updateCapture()
		{
			if (m_resolution.reset&BGFX_RESET_CAPTURE)
			{
				m_captureSize = m_resolution.width*m_resolution.height*4;
				m_capture = bx::realloc(g_allocator, m_capture, m_captureSize);
				g_callback->captureBegin(m_resolution.width, m_resolution.height, m_resolution.width*4, TextureFormat::BGRA8, false);
			}
			else
			{
				captureFinish();
			}
		}

		void capture()
		{
			if (NULL != m_capture)
			{
				if (NULL == m_screenshotTarget)
				{
					return;
				}

				m_renderCommandEncoder->endEncoding();

				m_cmd.kick(false, true);
				m_commandBuffer = 0;

				MTL::Region region(0, 0, 0, m_resolution.width, m_resolution.height, 1);

				const uint8_t  bpp   = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(m_resolution.formatColor) );
				const uint32_t pitch = m_resolution.width * bpp / 8;

				m_screenshotTarget->getBytes(m_capture, pitch, 0, region, 0, 0);

				m_commandBuffer = m_cmd.alloc();

				g_callback->captureFrame(m_capture, m_captureSize);

				MTL::RenderPassDescriptor* renderPassDescriptor = newRenderPassDescriptor();
				setFrameBuffer(renderPassDescriptor, m_renderCommandEncoderFrameBufferHandle);

				for (uint32_t ii = 0; ii < g_caps.limits.maxFBAttachments; ++ii)
				{
					MTL::RenderPassColorAttachmentDescriptor* desc = renderPassDescriptor->colorAttachments()->object(ii);

					if (NULL != desc->texture() )
					{
						desc->setLoadAction(MTL::LoadActionLoad);
						desc->setStoreAction(desc->resolveTexture() == NULL
							? MTL::StoreActionStore
							: MTL::StoreActionMultisampleResolve)
							;
					}
				}

				MTL::RenderPassDepthAttachmentDescriptor* depthAttachment = renderPassDescriptor->depthAttachment();

				if (NULL != depthAttachment->texture() )
				{
					depthAttachment->setLoadAction(MTL::LoadActionLoad);
					depthAttachment->setStoreAction(depthAttachment->resolveTexture() == NULL
						? MTL::StoreActionStore
						: MTL::StoreActionMultisampleResolve)
						;
				}

				MTL::RenderPassStencilAttachmentDescriptor* stencilAttachment = renderPassDescriptor->stencilAttachment();

				if (NULL != stencilAttachment->texture() )
				{
					stencilAttachment->setLoadAction(MTL::LoadActionLoad);
					stencilAttachment->setStoreAction(stencilAttachment->resolveTexture() == NULL
						? MTL::StoreActionStore
						: MTL::StoreActionMultisampleResolve)
						;
				}

				m_renderCommandEncoder = m_commandBuffer->renderCommandEncoder(renderPassDescriptor);
				MTL_RELEASE(renderPassDescriptor, 0);

				if (m_depthClamp)
				{
					m_renderCommandEncoder->setDepthClipMode(MTL::DepthClipModeClamp);
				}
			}
		}

		void captureFinish()
		{
			if (NULL != m_capture)
			{
				g_callback->captureEnd();
				bx::free(g_allocator, m_capture);
				m_capture     = NULL;
				m_captureSize = 0;
			}
		}


		void setShaderUniform(uint8_t _flags, uint32_t _loc, const void* _val, uint32_t _numRegs)
		{
			const uint32_t offset = 0 != (_flags&kUniformFragmentBit)
				? m_uniformBufferFragmentOffset
				: m_uniformBufferVertexOffset
				;
			uint8_t* dst = (uint8_t*)m_uniformBuffer->contents();
			bx::memCopy(&dst[offset + _loc], _val, _numRegs*16);
		}

		void setShaderUniform4f(uint8_t _flags, uint32_t _loc, const void* _val, uint32_t _numRegs)
		{
			setShaderUniform(_flags, _loc, _val, _numRegs);
		}

		void setShaderUniform4x4f(uint8_t _flags, uint32_t _loc, const void* _val, uint32_t _numRegs)
		{
			setShaderUniform(_flags, _loc, _val, _numRegs);
		}

		void commit(UniformBuffer& _uniformBuffer)
		{
			_uniformBuffer.reset();

			for (;;)
			{
				uint32_t opcode = _uniformBuffer.read();

				if (UniformType::End == opcode)
				{
					break;
				}

				uint8_t type;
				uint16_t loc;
				uint16_t num;
				uint16_t copy;
				UniformBuffer::decodeOpcode(opcode, type, loc, num, copy);

				const char* data;
				if (copy)
				{
					data = _uniformBuffer.read(g_uniformTypeSize[type]*num);
				}
				else
				{
					UniformHandle handle;
					bx::memCopy(&handle, _uniformBuffer.read(sizeof(UniformHandle) ), sizeof(UniformHandle) );
					data = (const char*)m_uniforms[handle.idx];
				}

				switch (type)
				{
				case UniformType::Mat3:
				case UniformType::Mat3|kUniformFragmentBit:
					{
						float* value = (float*)data;
						for (uint32_t ii = 0, count = num/3; ii < count; ++ii,  loc += 3*16, value += 9)
						{
							Matrix4 mtx;
							mtx.un.val[ 0] = value[0];
							mtx.un.val[ 1] = value[1];
							mtx.un.val[ 2] = value[2];
							mtx.un.val[ 3] = 0.0f;
							mtx.un.val[ 4] = value[3];
							mtx.un.val[ 5] = value[4];
							mtx.un.val[ 6] = value[5];
							mtx.un.val[ 7] = 0.0f;
							mtx.un.val[ 8] = value[6];
							mtx.un.val[ 9] = value[7];
							mtx.un.val[10] = value[8];
							mtx.un.val[11] = 0.0f;
							setShaderUniform(uint8_t(type), loc, &mtx.un.val[0], 3);
						}
					}
					break;

				case UniformType::Sampler:
				case UniformType::Sampler | kUniformFragmentBit:
				case UniformType::Vec4:
				case UniformType::Vec4 | kUniformFragmentBit:
				case UniformType::Mat4:
				case UniformType::Mat4 | kUniformFragmentBit:
					{
						setShaderUniform(uint8_t(type), loc, data, num);
					}
					break;

				case UniformType::End:
					break;

				default:
					BX_TRACE("%4d: INVALID 0x%08x, t %d, l %d, n %d, c %d", _uniformBuffer.getPos(), opcode, type, loc, num, copy);
					break;
				}
			}
		}

		void clearQuad(const ClearQuad& _clearQuad, const Rect& /*_rect*/, const Clear& _clear, const float _palette[][4])
		{
			uint64_t state = 0;
			state |= _clear.m_flags & BGFX_CLEAR_COLOR ? BGFX_STATE_WRITE_RGB|BGFX_STATE_WRITE_A         : 0;
			state |= _clear.m_flags & BGFX_CLEAR_DEPTH ? BGFX_STATE_DEPTH_TEST_ALWAYS|BGFX_STATE_WRITE_Z : 0;

			uint64_t stencil = 0;
			stencil |= _clear.m_flags & BGFX_CLEAR_STENCIL ? 0
				| BGFX_STENCIL_TEST_ALWAYS
				| BGFX_STENCIL_FUNC_REF(_clear.m_stencil)
				| BGFX_STENCIL_FUNC_RMASK(0xff)
				| BGFX_STENCIL_OP_FAIL_S_REPLACE
				| BGFX_STENCIL_OP_FAIL_Z_REPLACE
				| BGFX_STENCIL_OP_PASS_Z_REPLACE
				: 0
				;

			setDepthStencilState(state, stencil);

			uint32_t numMrt = 1;
			FrameBufferHandle fbh = m_fbh;
			if (isValid(fbh)
			&&  NULL == m_frameBuffers[fbh.idx].m_swapChain)
			{
				const FrameBufferMtl& fb = m_frameBuffers[fbh.idx];
				numMrt = bx::max(1, fb.m_num);
			}

			const VertexLayout* layout  = &m_vertexLayouts[_clearQuad.m_layout.idx];
			const PipelineStateMtl* pso = getPipelineState(
				  state
				, 0
				, fbh
				, 1
				, &layout
				, _clearQuad.m_program[numMrt-1]
				, 0
				);
			m_renderCommandEncoder->setRenderPipelineState(pso->m_rps);

			const uint32_t vertexUniformBufferSize   = pso->m_vshConstantBufferSize;
			const uint32_t fragmentUniformBufferSize = pso->m_fshConstantBufferSize;

			if (0 != vertexUniformBufferSize)
			{
				m_uniformBufferVertexOffset = bx::alignUp(
					  m_uniformBufferVertexOffset
					, pso->m_vshConstantBufferAlignment
					);
				m_renderCommandEncoder->setVertexBuffer(m_uniformBuffer, m_uniformBufferVertexOffset, 0);
			}

			m_uniformBufferFragmentOffset = m_uniformBufferVertexOffset + vertexUniformBufferSize;
			if (fragmentUniformBufferSize)
			{
				m_uniformBufferFragmentOffset = bx::alignUp(
					  m_uniformBufferFragmentOffset
					, pso->m_fshConstantBufferAlignment
					);
				m_renderCommandEncoder->setFragmentBuffer(m_uniformBuffer, m_uniformBufferFragmentOffset, 0);
			}

			const float mrtClearDepth[4] = { _clear.m_depth };
			float mrtClearColor[BGFX_CONFIG_MAX_FRAME_BUFFER_ATTACHMENTS][4];

			if (BGFX_CLEAR_COLOR_USE_PALETTE & _clear.m_flags)
			{
				for (uint32_t ii = 0; ii < numMrt; ++ii)
				{
					uint8_t index = (uint8_t)bx::min(BGFX_CONFIG_MAX_COLOR_PALETTE-1, _clear.m_index[ii]);
					bx::memCopy(mrtClearColor[ii], _palette[index], 16);
				}
			}
			else
			{
				float rgba[4] =
				{
					_clear.m_index[0]*1.0f/255.0f,
					_clear.m_index[1]*1.0f/255.0f,
					_clear.m_index[2]*1.0f/255.0f,
					_clear.m_index[3]*1.0f/255.0f,
				};

				for (uint32_t ii = 0; ii < numMrt; ++ii)
				{
					bx::memCopy(mrtClearColor[ii], rgba, 16);
				}
			}

			bx::memCopy(
				  (uint8_t*)m_uniformBuffer->contents() + m_uniformBufferVertexOffset
				, mrtClearDepth
				, bx::min(vertexUniformBufferSize, sizeof(mrtClearDepth) )
				);

			bx::memCopy(
				  (uint8_t*)m_uniformBuffer->contents() + m_uniformBufferFragmentOffset
				, mrtClearColor
				, bx::min(fragmentUniformBufferSize, sizeof(mrtClearColor) )
				);

			m_uniformBufferFragmentOffset += fragmentUniformBufferSize;
			m_uniformBufferVertexOffset    = m_uniformBufferFragmentOffset;

			const VertexBufferMtl& vb = m_vertexBuffers[_clearQuad.m_vb.idx];

			m_renderCommandEncoder->setCullMode( (MTL::CullMode)MTL::CullModeNone);
			m_renderCommandEncoder->setVertexBuffer(vb.m_ptr, 0, 1);
			m_renderCommandEncoder->drawPrimitives(MTL::PrimitiveTypeTriangleStrip, 0, 4, 1);
		}

		void setAttachment(MTL::RenderPassAttachmentDescriptor* _attachmentDescriptor, const Attachment& _at, uint8_t _textureType, bool _resolve)
		{
			_attachmentDescriptor->setLevel(_at.mip);

			if (TextureMtl::Texture3D == _textureType)
			{
				_attachmentDescriptor->setDepthPlane(_at.layer);
			}
			else
			{
				_attachmentDescriptor->setSlice(_at.layer);
			}

			if (_resolve)
			{
				_attachmentDescriptor->setResolveLevel(_at.mip);

				if (TextureMtl::Texture3D == _textureType)
				{
					_attachmentDescriptor->setResolveDepthPlane(_at.layer);
				}
				else
				{
					_attachmentDescriptor->setResolveSlice(_at.layer);
				}
			}
		}

		void setFrameBuffer(MTL::RenderPassDescriptor* _renderPassDescriptor, FrameBufferHandle _fbh, bool _msaa = true)
		{
			// resolve framebuffer
			if (isValid(m_fbh) && m_fbh.idx != _fbh.idx)
			{
				FrameBufferMtl& frameBuffer = m_frameBuffers[m_fbh.idx];
				frameBuffer.resolve();
			}

			if (!isValid(_fbh)
			||  m_frameBuffers[_fbh.idx].m_swapChain)
			{
				SwapChainMtl* swapChain = !isValid(_fbh)
					? m_mainFrameBuffer.m_swapChain
					: m_frameBuffers[_fbh.idx].m_swapChain
					;

				if (NULL != swapChain)
				{
					if (NULL != swapChain->m_backBufferColorMsaa)
					{
						_renderPassDescriptor->colorAttachments()->object(0)->setTexture(swapChain->m_backBufferColorMsaa);
						_renderPassDescriptor->colorAttachments()->object(0)->setResolveTexture(NULL != m_screenshotTarget
							? m_screenshotTarget
							: swapChain->currentDrawableTexture()
							);
					}
					else
					{
						_renderPassDescriptor->colorAttachments()->object(0)->setTexture(NULL != m_screenshotTarget
							? m_screenshotTarget
							: swapChain->currentDrawableTexture()
							);
					}

					{
						_renderPassDescriptor->depthAttachment()->setTexture(swapChain->m_backBufferDepth);
						_renderPassDescriptor->stencilAttachment()->setTexture(swapChain->m_backBufferStencil);
					}
				}
			}
			else
			{
				FrameBufferMtl& frameBuffer = m_frameBuffers[_fbh.idx];

				for (uint32_t ii = 0; ii < frameBuffer.m_num; ++ii)
				{
					const TextureMtl& texture = m_textures[frameBuffer.m_colorHandle[ii].idx];
					_renderPassDescriptor->colorAttachments()->object(ii)->setTexture(texture.m_ptrMsaa
						? texture.m_ptrMsaa
						: texture.m_ptr
						);
					_renderPassDescriptor->colorAttachments()->object(ii)->setResolveTexture(texture.m_ptrMsaa
						? texture.m_ptr
						: NULL
						);

					setAttachment( (MTL::RenderPassAttachmentDescriptor*)_renderPassDescriptor->colorAttachments()->object(ii), frameBuffer.m_colorAttachment[ii], texture.m_type, texture.m_ptrMsaa != NULL);
				}

				if (isValid(frameBuffer.m_depthHandle) )
				{
					const TextureMtl& texture = m_textures[frameBuffer.m_depthHandle.idx];
					_renderPassDescriptor->depthAttachment()->setTexture(texture.m_ptrMsaa
						? texture.m_ptrMsaa
						: texture.m_ptr
						);
					_renderPassDescriptor->stencilAttachment()->setTexture(texture.m_ptrStencil);

					setAttachment( (MTL::RenderPassAttachmentDescriptor*)_renderPassDescriptor->depthAttachment(), frameBuffer.m_depthAttachment, texture.m_type, NULL != texture.m_ptrMsaa);
					setAttachment( (MTL::RenderPassAttachmentDescriptor*)_renderPassDescriptor->stencilAttachment(), frameBuffer.m_depthAttachment, texture.m_type, NULL != texture.m_ptrMsaa);

					if (texture.m_textureFormat == TextureFormat::D24S8)
					{
						const MTL::PixelFormat depthFormat = texture.m_ptr->pixelFormat();

						if (MTL::PixelFormatDepth24Unorm_Stencil8 == depthFormat
						||  MTL::PixelFormatDepth32Float_Stencil8 == depthFormat)
						{
							_renderPassDescriptor->stencilAttachment()->setTexture(_renderPassDescriptor->depthAttachment()->texture() );
						}
						else
						{
							_renderPassDescriptor->stencilAttachment()->setTexture(texture.m_ptrMsaa
								? texture.m_ptrMsaa
								: texture.m_ptrStencil
								);
						}
					}
				}
			}

			m_fbh    = _fbh;
			m_rtMsaa = _msaa;
		}

		bool hasDepth(FrameBufferHandle _fbh)
		{
			if (!isValid(_fbh) )
			{
				return NULL != m_mainFrameBuffer.m_swapChain
					&& NULL != m_mainFrameBuffer.m_swapChain->m_backBufferDepth
					;
			}

			const FrameBufferMtl& fb = m_frameBuffers[_fbh.idx];
			if (NULL != fb.m_swapChain)
			{
				return NULL != fb.m_swapChain->m_backBufferDepth;
			}

			return isValid(fb.m_depthHandle);
		}

		void setDepthStencilState(uint64_t _state, uint64_t _stencil = 0)
		{
			_state &= BGFX_STATE_WRITE_Z|BGFX_STATE_DEPTH_TEST_MASK;

			if (!hasDepth(m_fbh) )
			{
				_state &= ~(BGFX_STATE_WRITE_Z|BGFX_STATE_DEPTH_TEST_MASK);
			}

			uint32_t fstencil = unpackStencil(0, _stencil);
			uint32_t ref      = (fstencil&BGFX_STENCIL_FUNC_REF_MASK)>>BGFX_STENCIL_FUNC_REF_SHIFT;

			_stencil &= kStencilNoRefMask;

			bx::HashMurmur2A murmur;
			murmur.begin();
			murmur.add(_state);
			murmur.add(_stencil);
			uint32_t hash = murmur.end();

			MTL::DepthStencilState* dss = m_depthStencilStateCache.find(hash);

			if (NULL == dss)
			{
				MTL::DepthStencilDescriptor* desc = m_depthStencilDescriptor;
				uint32_t func = (_state&BGFX_STATE_DEPTH_TEST_MASK)>>BGFX_STATE_DEPTH_TEST_SHIFT;
				desc->setDepthWriteEnabled(!!(BGFX_STATE_WRITE_Z & _state) );
				desc->setDepthCompareFunction( (MTL::CompareFunction)s_cmpFunc[func]);

				uint32_t bstencil = unpackStencil(1, _stencil);
				uint32_t frontAndBack = bstencil != BGFX_STENCIL_NONE && bstencil != fstencil;
				bstencil = frontAndBack ? bstencil : fstencil;

				if (0 != _stencil)
				{
					MTL::StencilDescriptor* frontFaceDesc = m_frontFaceStencilDescriptor;
					MTL::StencilDescriptor* backfaceDesc  = m_backFaceStencilDescriptor;

					uint32_t readMask  = (fstencil&BGFX_STENCIL_FUNC_RMASK_MASK)>>BGFX_STENCIL_FUNC_RMASK_SHIFT;
					uint32_t writeMask = 0xff;

					frontFaceDesc->setStencilFailureOperation(   (MTL::StencilOperation)s_stencilOp[(fstencil&BGFX_STENCIL_OP_FAIL_S_MASK)>>BGFX_STENCIL_OP_FAIL_S_SHIFT]);
					frontFaceDesc->setDepthFailureOperation(     (MTL::StencilOperation)s_stencilOp[(fstencil&BGFX_STENCIL_OP_FAIL_Z_MASK)>>BGFX_STENCIL_OP_FAIL_Z_SHIFT]);
					frontFaceDesc->setDepthStencilPassOperation( (MTL::StencilOperation)s_stencilOp[(fstencil&BGFX_STENCIL_OP_PASS_Z_MASK)>>BGFX_STENCIL_OP_PASS_Z_SHIFT]);
					frontFaceDesc->setStencilCompareFunction(    (MTL::CompareFunction)s_cmpFunc[(fstencil&BGFX_STENCIL_TEST_MASK)>>BGFX_STENCIL_TEST_SHIFT]);
					frontFaceDesc->setReadMask(readMask);
					frontFaceDesc->setWriteMask(writeMask);

					backfaceDesc->setStencilFailureOperation(   (MTL::StencilOperation)s_stencilOp[(bstencil&BGFX_STENCIL_OP_FAIL_S_MASK)>>BGFX_STENCIL_OP_FAIL_S_SHIFT]);
					backfaceDesc->setDepthFailureOperation(     (MTL::StencilOperation)s_stencilOp[(bstencil&BGFX_STENCIL_OP_FAIL_Z_MASK)>>BGFX_STENCIL_OP_FAIL_Z_SHIFT]);
					backfaceDesc->setDepthStencilPassOperation( (MTL::StencilOperation)s_stencilOp[(bstencil&BGFX_STENCIL_OP_PASS_Z_MASK)>>BGFX_STENCIL_OP_PASS_Z_SHIFT]);
					backfaceDesc->setStencilCompareFunction(    (MTL::CompareFunction)s_cmpFunc[(bstencil&BGFX_STENCIL_TEST_MASK)>>BGFX_STENCIL_TEST_SHIFT]);
					backfaceDesc->setReadMask(readMask);
					backfaceDesc->setWriteMask(writeMask);

					desc->setFrontFaceStencil(frontFaceDesc);
					desc->setBackFaceStencil(backfaceDesc);
				}
				else
				{
					desc->setBackFaceStencil(NULL);
					desc->setFrontFaceStencil(NULL);
				}

				dss = m_device->newDepthStencilState(desc);

				m_depthStencilStateCache.add(hash, dss);
			}

			m_renderCommandEncoder->setDepthStencilState(dss);
			m_renderCommandEncoder->setStencilReferenceValue(ref);
		}

		void processArguments(
			  PipelineStateMtl* ps
			, NS::Array* _vertexArgs
			, NS::Array* _fragmentArgs
			)
		{
			ps->m_numPredefined = 0;

			for (uint32_t shaderType = 0; shaderType < 2; ++shaderType)
			{
				UniformBuffer*& constantBuffer = shaderType == 0
					? ps->m_vshConstantBuffer
					: ps->m_fshConstantBuffer
					;
				const int8_t fragmentBit = (1 == shaderType ? kUniformFragmentBit : 0);

				NS::Array* args = shaderType == 0 ? _vertexArgs : _fragmentArgs;
				if (NULL == args)
				{
					continue;
				}

				for (NS::UInteger argIdx = 0, argCount = args->count(); argIdx < argCount; ++argIdx)
				{
					// Both MTL::Binding and MTL::Argument respond to the same selectors
					// for name, type, index, and buffer properties.
					MTL::Argument* arg = (MTL::Argument*)args->object(argIdx);

					BX_TRACE("arg: %s type:%d", utf8String(arg->name() ), arg->type() );

					const bool isArgActive = m_usesMTLBindings
						? ( (MTL::Binding*)arg)->isUsed()
						: arg->isActive()
						;

					if (isArgActive)
					{
						if ( (NS::UInteger)arg->type() == MTL::BindingTypeBuffer)
						{
							if (0 == bx::strCmp(utf8String(arg->name() ), SHADER_UNIFORM_NAME) )
							{
								BX_ASSERT(arg->index() == 0, "Uniform buffer must be in the buffer slot 0.");

								BX_ASSERT(
									  MTL::DataTypeStruct == arg->bufferDataType()
									, SHADER_UNIFORM_NAME "'s type must be a struct"
									);

								if (MTL::DataTypeStruct == arg->bufferDataType() )
								{
									if (shaderType == 0)
									{
										ps->m_vshConstantBufferSize      = uint32_t(arg->bufferDataSize() );
										ps->m_vshConstantBufferAlignment = uint32_t(arg->bufferAlignment() );
									}
									else
									{
										ps->m_fshConstantBufferSize      = uint32_t(arg->bufferDataSize() );
										ps->m_fshConstantBufferAlignment = uint32_t(arg->bufferAlignment() );
									}

									NS::Array* members = arg->bufferStructType()->members();

									for (NS::UInteger mi = 0, mc = members->count(); mi < mc; ++mi)
									{
										MTL::StructMember* uniform = (MTL::StructMember*)members->object(mi);
										const char* name = utf8String(uniform->name() );
										BX_TRACE("uniform: %s type:%d", name, uniform->dataType() );

										MTL::DataType dataType = uniform->dataType();
										uint32_t num = 1;

										if (dataType == MTL::DataTypeArray)
										{
											dataType = uniform->arrayType()->elementType();
											num = (uint32_t)uniform->arrayType()->arrayLength();
										}

										switch (dataType)
										{
										case MTL::DataTypeFloat4:   num *= 1; break;
										case MTL::DataTypeFloat4x4: num *= 4; break;
										case MTL::DataTypeFloat3x3: num *= 3; break;

										default:
											BX_WARN(0, "Unsupported uniform MTL::DataType: %d", uniform->dataType() );
											break;
										}

										const PredefinedUniform::Enum predefined = nameToPredefinedUniformEnum(name);

										if (PredefinedUniform::Count != predefined)
										{
											ps->m_predefined[ps->m_numPredefined].m_loc   = uint32_t(uniform->offset() );
											ps->m_predefined[ps->m_numPredefined].m_count = uint16_t(num);
											ps->m_predefined[ps->m_numPredefined].m_type  = uint8_t(predefined|fragmentBit);
											++ps->m_numPredefined;
										}
										else
										{
											const UniformRegInfo* info = s_renderMtl->m_uniformReg.find(name);
											BX_WARN(NULL != info, "User defined uniform '%s' is not found, it won't be set.", name);

											if (NULL != info)
											{
												if (NULL == constantBuffer)
												{
													constantBuffer = UniformBuffer::create(1024);
												}

												UniformType::Enum type = convertMtlType(dataType);
												constantBuffer->writeUniformHandle(type|fragmentBit, uint32_t(uniform->offset() ), info->m_handle, uint16_t(num) );
												BX_TRACE("store %s %d offset:%d", name, info->m_handle, uint32_t(uniform->offset() ) );
											}
										}
									}
								}
							}
							else if (arg->index() > 0
								 &&  NULL != arg->bufferStructType() )
							{
								const char* name = utf8String(arg->name() );
								BX_UNUSED(name);

								if (arg->index() >= BGFX_CONFIG_MAX_TEXTURE_SAMPLERS)
								{
									BX_TRACE(
										"Binding index is too large %d max is %d. "
										"User defined uniform '%s' won't be set."
										, int32_t(arg->index() - 1)
										, BGFX_CONFIG_MAX_TEXTURE_SAMPLERS - 1
										, name
										);
								}
								else
								{
									ps->m_bindingTypes[arg->index()-1] |= fragmentBit
										? PipelineStateMtl::BindToFragmentShader
										: PipelineStateMtl::BindToVertexShader
										;
									BX_TRACE("Buffer %s index: %d", name, int32_t(arg->index()-1) );
								}
							}
						}
						else if ( (NS::UInteger)arg->type() == MTL::BindingTypeTexture)
						{
							const char* name = utf8String(arg->name() );

							if (arg->index() >= BGFX_CONFIG_MAX_TEXTURE_SAMPLERS)
							{
								BX_WARN(false, "Binding index is too large %d max is %d. User defined uniform '%s' won't be set.", int(arg->index() ), BGFX_CONFIG_MAX_TEXTURE_SAMPLERS - 1, name);
							}
							else
							{
								ps->m_bindingTypes[arg->index()] |= fragmentBit
									? PipelineStateMtl::BindToFragmentShader
									: PipelineStateMtl::BindToVertexShader
									;

								const UniformRegInfo* info = s_renderMtl->m_uniformReg.find(name);

								if (info)
								{
									BX_TRACE("texture %s %d index:%d", name, info->m_handle, uint32_t(arg->index() ) );
								}
								else
								{
									BX_TRACE("image %s index:%d", name, uint32_t(arg->index() ) );
								}
							}
						}
						else if ( (NS::UInteger)arg->type() == MTL::BindingTypeSampler)
						{
							BX_TRACE("sampler: %s index:%d", utf8String(arg->name() ), arg->index() );
						}
					}
				}

				if (NULL != constantBuffer)
				{
					constantBuffer->finish();
				}
			}
		}

		PipelineStateMtl* getPipelineState(
			  uint64_t _state
			, uint32_t _rgba
			, FrameBufferHandle _fbh
			, uint8_t _numStreams
			, const VertexLayout** _layouts
			, ProgramHandle _program
			, uint8_t _numInstanceData
			)
		{
			_state &= (0
				| BGFX_STATE_BLEND_MASK
				| BGFX_STATE_BLEND_EQUATION_MASK
				| BGFX_STATE_WRITE_RGB
				| BGFX_STATE_WRITE_A
				| BGFX_STATE_BLEND_INDEPENDENT
				| BGFX_STATE_MSAA
				| BGFX_STATE_BLEND_ALPHA_TO_COVERAGE
				);

			const bool independentBlendEnable = !!(BGFX_STATE_BLEND_INDEPENDENT & _state);
			const ProgramMtl& program = m_program[_program.idx];

			bx::HashMurmur2A murmur;
			murmur.begin();
			murmur.add(_state);
			murmur.add(independentBlendEnable ? _rgba : 0);
			murmur.add(_numInstanceData);

			if (!isValid(_fbh) )
			{
				murmur.add(m_mainFrameBuffer.m_pixelFormatHash);
			}
			else
			{
				FrameBufferMtl& frameBuffer = m_frameBuffers[_fbh.idx];
				murmur.add(frameBuffer.m_pixelFormatHash);
			}

			murmur.add(program.m_vsh->m_hash);
			if (NULL != program.m_fsh)
			{
				murmur.add(program.m_fsh->m_hash);
			}

			for (uint8_t ii = 0; ii < _numStreams; ++ii)
			{
				murmur.add(_layouts[ii]->m_hash);
			}

			uint32_t hash = murmur.end();

			PipelineStateMtl* pso = m_pipelineStateCache.find(hash);

			if (NULL == pso)
			{
				pso = BX_NEW(g_allocator, PipelineStateMtl);

				MTL::RenderPipelineDescriptor* pd = m_renderPipelineDescriptor;
				reset(pd);

				pd->setAlphaToCoverageEnabled(!!(BGFX_STATE_BLEND_ALPHA_TO_COVERAGE & _state) );

				uint32_t frameBufferAttachment = 1;

				if (!isValid(_fbh)
				||  s_renderMtl->m_frameBuffers[_fbh.idx].m_swapChain)
				{
					SwapChainMtl* swapChain = !isValid(_fbh)
						? s_renderMtl->m_mainFrameBuffer.m_swapChain
						: s_renderMtl->m_frameBuffers[_fbh.idx].m_swapChain
						;

					if (NULL != swapChain)
					{
						pd->setRasterSampleCount(NULL != swapChain->m_backBufferColorMsaa
							? swapChain->m_backBufferColorMsaa->sampleCount()
							: 1
							);
						pd->colorAttachments()->object(0)->setPixelFormat(swapChain->currentDrawableTexture()->pixelFormat() );
						{
							pd->setDepthAttachmentPixelFormat(NULL != swapChain->m_backBufferDepth
								? swapChain->m_backBufferDepth->pixelFormat()
								: MTL::PixelFormatInvalid)
								;
						}

						pd->setStencilAttachmentPixelFormat(NULL != swapChain->m_backBufferStencil
							? swapChain->m_backBufferStencil->pixelFormat()
							: MTL::PixelFormatInvalid)
							;
					}
				}
				else
				{
					const FrameBufferMtl& frameBuffer = m_frameBuffers[_fbh.idx];
					frameBufferAttachment = frameBuffer.m_num;

					for (uint32_t ii = 0; ii < frameBuffer.m_num; ++ii)
					{
						const TextureMtl& texture = m_textures[frameBuffer.m_colorHandle[ii].idx];
						pd->setRasterSampleCount(NULL != texture.m_ptrMsaa
							? texture.m_ptrMsaa->sampleCount()
							: 1
							);
						pd->colorAttachments()->object(ii)->setPixelFormat(texture.m_ptr->pixelFormat() );
					}

					if (isValid(frameBuffer.m_depthHandle) )
					{
						const TextureMtl& depthStencilTexture = m_textures[frameBuffer.m_depthHandle.idx];
						pd->setDepthAttachmentPixelFormat(depthStencilTexture.m_ptr->pixelFormat() );
						pd->setRasterSampleCount(NULL != depthStencilTexture.m_ptrMsaa
							? depthStencilTexture.m_ptrMsaa->sampleCount()
							: 1
							);

						if (NULL != depthStencilTexture.m_ptrStencil)
						{
							pd->setStencilAttachmentPixelFormat(depthStencilTexture.m_ptrStencil->pixelFormat() );
						}
						else if (depthStencilTexture.m_textureFormat == TextureFormat::D24S8)
						{
							pd->setStencilAttachmentPixelFormat(depthStencilTexture.m_ptr->pixelFormat() );
						}
					}
				}

				const uint32_t blend    = uint32_t( (_state&BGFX_STATE_BLEND_MASK         )>>BGFX_STATE_BLEND_SHIFT);
				const uint32_t equation = uint32_t( (_state&BGFX_STATE_BLEND_EQUATION_MASK)>>BGFX_STATE_BLEND_EQUATION_SHIFT);

				const uint32_t srcRGB = (blend    )&0xf;
				const uint32_t dstRGB = (blend>> 4)&0xf;
				const uint32_t srcA   = (blend>> 8)&0xf;
				const uint32_t dstA   = (blend>>12)&0xf;

				const uint32_t equRGB = (equation   )&0x7;
				const uint32_t equA   = (equation>>3)&0x7;

				uint8_t writeMask = 0;
				writeMask |= (_state&BGFX_STATE_WRITE_R) ? MTL::ColorWriteMaskRed   : 0;
				writeMask |= (_state&BGFX_STATE_WRITE_G) ? MTL::ColorWriteMaskGreen : 0;
				writeMask |= (_state&BGFX_STATE_WRITE_B) ? MTL::ColorWriteMaskBlue  : 0;
				writeMask |= (_state&BGFX_STATE_WRITE_A) ? MTL::ColorWriteMaskAlpha : 0;

				for (uint32_t ii = 0; ii < (independentBlendEnable ? 1 : frameBufferAttachment); ++ii)
				{
					MTL::RenderPipelineColorAttachmentDescriptor* drt = pd->colorAttachments()->object(ii);

					drt->setBlendingEnabled(!!(BGFX_STATE_BLEND_MASK & _state) );

					drt->setSourceRGBBlendFactor(      (MTL::BlendFactor)s_blendFactor[srcRGB][0]);
					drt->setDestinationRGBBlendFactor(  (MTL::BlendFactor)s_blendFactor[dstRGB][0]);
					drt->setRgbBlendOperation(          (MTL::BlendOperation)s_blendEquation[equRGB]);

					drt->setSourceAlphaBlendFactor(     (MTL::BlendFactor)s_blendFactor[srcA][1]);
					drt->setDestinationAlphaBlendFactor( (MTL::BlendFactor)s_blendFactor[dstA][1]);
					drt->setAlphaBlendOperation(        (MTL::BlendOperation)s_blendEquation[equA]);

					drt->setWriteMask(writeMask);
				}

				if (independentBlendEnable)
				{
					for (uint32_t ii = 1, rgba = _rgba; ii < frameBufferAttachment; ++ii, rgba >>= 11)
					{
						MTL::RenderPipelineColorAttachmentDescriptor* drt = pd->colorAttachments()->object(ii);

						drt->setBlendingEnabled(0 != (rgba&0x7ff) );

						const uint32_t src           = (rgba   )&0xf;
						const uint32_t dst           = (rgba>>4)&0xf;
						const uint32_t equationIndex = (rgba>>8)&0x7;

						drt->setSourceRGBBlendFactor(     (MTL::BlendFactor)s_blendFactor[src][0]);
						drt->setDestinationRGBBlendFactor( (MTL::BlendFactor)s_blendFactor[dst][0]);
						drt->setRgbBlendOperation(        (MTL::BlendOperation)s_blendEquation[equationIndex]);

						drt->setSourceAlphaBlendFactor(     (MTL::BlendFactor)s_blendFactor[src][1]);
						drt->setDestinationAlphaBlendFactor( (MTL::BlendFactor)s_blendFactor[dst][1]);
						drt->setAlphaBlendOperation(        (MTL::BlendOperation)s_blendEquation[equationIndex]);

						drt->setWriteMask(writeMask);
					}
				}

				pd->setVertexFunction(program.m_vsh->m_function);
				pd->setFragmentFunction(program.m_fsh != NULL
					? program.m_fsh->m_function
					: NULL
					);

				MTL::VertexDescriptor* vertexDesc = m_vertexDescriptor;
				reset(vertexDesc);

				bool attrSet[Attrib::Count] = {};

				uint8_t stream = 0;
				for (; stream < _numStreams; ++stream)
				{
					const VertexLayout& layout = *_layouts[stream];
					bool streamUsed = false;
					for (uint32_t ii = 0; Attrib::Count != program.m_used[ii]; ++ii)
					{
						Attrib::Enum attr = Attrib::Enum(program.m_used[ii]);

						if (attrSet[attr])
						{
							continue;
						}

						const uint32_t loc = program.m_attributes[attr];

						uint8_t num;
						AttribType::Enum type;
						bool normalized;
						bool asInt;
						layout.decode(attr, num, type, normalized, asInt);
						BX_ASSERT(num <= 4, "num must be <= 4");

						if (UINT16_MAX != layout.m_attributes[attr])
						{
							vertexDesc->attributes()->object(loc)->setFormat( (MTL::VertexFormat)s_attribType[type][num-1][normalized?1:0]);
							vertexDesc->attributes()->object(loc)->setBufferIndex(stream+1);
							vertexDesc->attributes()->object(loc)->setOffset(layout.m_offset[attr]);

							BX_TRACE("attrib: %s format: %d offset: %d", s_attribName[attr], (int)vertexDesc->attributes()->object(loc)->format(), (int)vertexDesc->attributes()->object(loc)->offset() );

							attrSet[attr] = true;
							streamUsed = true;
						}
					}

					if (streamUsed)
					{
						vertexDesc->layouts()->object(stream+1)->setStride(layout.getStride() );
						vertexDesc->layouts()->object(stream+1)->setStepFunction(MTL::VertexStepFunctionPerVertex);
					}
				}

				for (uint32_t ii = 0; Attrib::Count != program.m_used[ii]; ++ii)
				{
					const Attrib::Enum attr = Attrib::Enum(program.m_used[ii]);
					const uint32_t loc = program.m_attributes[attr];

					if (!attrSet[attr])
					{
						vertexDesc->attributes()->object(loc)->setFormat(MTL::VertexFormatUChar2);
						vertexDesc->attributes()->object(loc)->setBufferIndex(1);
						vertexDesc->attributes()->object(loc)->setOffset(0);
					}
				}

				if (0 < _numInstanceData)
				{
					uint32_t numAttribs = 0;
					for (uint32_t ii = 0; ii < BX_COUNTOF(s_instanceDataName); ++ii)
					{
						const uint32_t loc = program.m_instanceData[ii];
						if (UINT32_MAX != loc)
						{
							vertexDesc->attributes()->object(loc)->setFormat(MTL::VertexFormatFloat4);
							vertexDesc->attributes()->object(loc)->setBufferIndex(stream+1);
							vertexDesc->attributes()->object(loc)->setOffset(ii*16);
							++numAttribs;
						}
					}

					if (0 < numAttribs)
					{
						vertexDesc->layouts()->object(stream+1)->setStride(_numInstanceData * 16);
						vertexDesc->layouts()->object(stream+1)->setStepFunction(MTL::VertexStepFunctionPerInstance);
						vertexDesc->layouts()->object(stream+1)->setStepRate(1);
					}
				}

				pd->setVertexDescriptor(vertexDesc);

				{
					MTL::RenderPipelineReflection* reflection = NULL;
					pso->m_rps = newRenderPipelineStateWithDescriptor(m_device, pd, MTL::PipelineOptionBufferTypeInfo, &reflection);

					if (NULL != reflection)
					{
						if (m_usesMTLBindings)
						{
							processArguments(pso, reflection->vertexBindings(), reflection->fragmentBindings() );
						}
						else
						{
							processArguments(pso, reflection->vertexArguments(), reflection->fragmentArguments() );
						}
					}
				}

				m_pipelineStateCache.add(hash, pso);
				m_pipelineProgram.push_back({hash, _program});
			}

			return pso;
		}

		PipelineStateMtl* getPipelineState(
			  uint64_t _state
			, uint32_t _rgba
			, FrameBufferHandle _fbh
			, VertexLayoutHandle _layoutHandle
			, ProgramHandle _program
			, uint16_t _numInstanceData
			)
		{
			const VertexLayout* layout = &m_vertexLayouts[_layoutHandle.idx];
			return getPipelineState(
				  _state
				, _rgba
				, _fbh
				, 1
				, &layout
				, _program
				, _numInstanceData
				);
		}

		PipelineStateMtl* getComputePipelineState(ProgramHandle _program)
		{
			ProgramMtl& program = m_program[_program.idx];

			if (NULL == program.m_computePS)
			{
				PipelineStateMtl* pso = BX_NEW(g_allocator, PipelineStateMtl);
				program.m_computePS = pso;

				MTL::ComputePipelineReflection* reflection = NULL;
				pso->m_cps = newComputePipelineStateWithFunction(m_device,
					  program.m_vsh->m_function
					, MTL::PipelineOptionBufferTypeInfo
					, &reflection
					);

				if (m_usesMTLBindings)
				{
					processArguments(pso, reflection->bindings(), NULL);
				}
				else
				{
					processArguments(pso, reflection->arguments(), NULL);
				}

				for (uint32_t ii = 0; ii < 3; ++ii)
				{
					pso->m_numThreads[ii] = program.m_vsh->m_numThreads[ii];
				}
			}

			return program.m_computePS;
		}

		MTL::SamplerState* getSamplerState(uint32_t _flags)
		{
			_flags &= BGFX_SAMPLER_BITS_MASK;
			MTL::SamplerState* sampler = m_samplerStateCache.find(_flags);

			if (NULL == sampler)
			{
				MTL::SamplerDescriptor* desc = m_samplerDescriptor;

				desc->setSAddressMode(  s_textureAddress[(_flags & BGFX_SAMPLER_U_MASK  ) >> BGFX_SAMPLER_U_SHIFT  ]);
				desc->setTAddressMode(  s_textureAddress[(_flags & BGFX_SAMPLER_V_MASK  ) >> BGFX_SAMPLER_V_SHIFT  ]);
				desc->setRAddressMode(  s_textureAddress[(_flags & BGFX_SAMPLER_W_MASK  ) >> BGFX_SAMPLER_W_SHIFT  ]);
				desc->setMinFilter(s_textureFilterMinMag[(_flags & BGFX_SAMPLER_MIN_MASK) >> BGFX_SAMPLER_MIN_SHIFT]);
				desc->setMagFilter(s_textureFilterMinMag[(_flags & BGFX_SAMPLER_MAG_MASK) >> BGFX_SAMPLER_MAG_SHIFT]);
				desc->setMipFilter(   s_textureFilterMip[(_flags & BGFX_SAMPLER_MIP_MASK) >> BGFX_SAMPLER_MIP_SHIFT]);
				desc->setLodMinClamp(0);
				desc->setLodMaxClamp(FLT_MAX);
				desc->setNormalizedCoordinates(TRUE);
				desc->setMaxAnisotropy(true
					&& NULL != m_mainFrameBuffer.m_swapChain
					&& (0 != (_flags & (BGFX_SAMPLER_MIN_ANISOTROPIC|BGFX_SAMPLER_MAG_ANISOTROPIC) ) )
						? m_mainFrameBuffer.m_swapChain->m_maxAnisotropy
						: 1
					);

				if (0 != (g_caps.supported & BGFX_CAPS_TEXTURE_COMPARE_ALL) )
				{
					const uint32_t cmpFunc = (_flags&BGFX_SAMPLER_COMPARE_MASK)>>BGFX_SAMPLER_COMPARE_SHIFT;
					desc->setCompareFunction(0 == cmpFunc
						? MTL::CompareFunctionNever
						: (MTL::CompareFunction)s_cmpFunc[cmpFunc])
						;
				}

				sampler = m_device->newSamplerState(desc);
				m_samplerStateCache.add(_flags, sampler);
			}

			return sampler;
		}

		bool isVisible(Frame* _render, OcclusionQueryHandle _handle, bool _visible)
		{
			m_occlusionQuery.resolve(_render);
			return _visible == (0 != _render->m_occlusion[_handle.idx]);
		}

		MTL::BlitCommandEncoder* getBlitCommandEncoder()
		{
			if (NULL == m_blitCommandEncoder)
			{
				endEncoding();

				if (NULL == m_commandBuffer)
				{
					m_commandBuffer = m_cmd.alloc();
				}

				m_blitCommandEncoder = m_commandBuffer->blitCommandEncoder();
			}

			return m_blitCommandEncoder;
		}

		void endEncoding()
		{
			if (NULL != m_renderCommandEncoder)
			{
				m_renderCommandEncoder->endEncoding();
				m_renderCommandEncoder = NULL;
			}

			if (NULL != m_computeCommandEncoder)
			{
				m_computeCommandEncoder->endEncoding();
				m_computeCommandEncoder = NULL;
			}

			if (NULL != m_blitCommandEncoder)
			{
				m_blitCommandEncoder->endEncoding();
				m_blitCommandEncoder = NULL;
			}
		}

		MTL::Device*      m_device;
		OcclusionQueryMTL m_occlusionQuery;
		TimerQueryMtl     m_gpuTimer;
		CommandQueueMtl   m_cmd;

		bool m_hasPixelFormatDepth32Float_Stencil8;
		bool m_hasStoreActionStoreAndMultisampleResolve;
		bool m_hasCPUCacheModesAndStorageModes;
		bool m_hasSynchronizeResource;
		bool m_usesMTLBindings;
		bool m_hasVSync;
		bool m_hasMaximumDrawableCount;

		MTL::Buffer* m_uniformBuffer;
		MTL::Buffer* m_uniformBuffers[BGFX_CONFIG_MAX_FRAME_LATENCY];
		uint32_t m_uniformBufferVertexOffset;
		uint32_t m_uniformBufferFragmentOffset;

		uint8_t  m_bufferIndex;

		uint16_t          m_numWindows;
		FrameBufferHandle m_windows[BGFX_CONFIG_MAX_FRAME_BUFFERS];

		IndexBufferMtl  m_indexBuffers[BGFX_CONFIG_MAX_INDEX_BUFFERS];
		VertexBufferMtl m_vertexBuffers[BGFX_CONFIG_MAX_VERTEX_BUFFERS];
		ShaderMtl       m_shaders[BGFX_CONFIG_MAX_SHADERS];
		ProgramMtl      m_program[BGFX_CONFIG_MAX_PROGRAMS];
		TextureMtl      m_textures[BGFX_CONFIG_MAX_TEXTURES];
		FrameBufferMtl  m_mainFrameBuffer;
		FrameBufferMtl  m_frameBuffers[BGFX_CONFIG_MAX_FRAME_BUFFERS];
		VertexLayout    m_vertexLayouts[BGFX_CONFIG_MAX_VERTEX_LAYOUTS];
		UniformRegistry m_uniformReg;
		void*           m_uniforms[BGFX_CONFIG_MAX_UNIFORMS];

		struct PipelineProgram
		{
			uint64_t      key;
			ProgramHandle program;
		};

		typedef stl::vector<PipelineProgram> PipelineProgramArray;

		PipelineProgramArray m_pipelineProgram;

		StateCacheT<PipelineStateMtl*>       m_pipelineStateCache;
		StateCacheT<MTL::DepthStencilState*> m_depthStencilStateCache;
		StateCacheT<MTL::SamplerState*>      m_samplerStateCache;

		TextVideoMem m_textVideoMem;

		FrameBufferHandle m_fbh;
		bool m_rtMsaa;

		Resolution m_resolution;
		void* m_capture;
		uint32_t m_captureSize;

		bool m_variableRateShadingSupported;
		bool m_supportsDepthClipMode;
		bool m_depthClamp;

		MTL::RenderPipelineDescriptor* m_renderPipelineDescriptor;
		MTL::DepthStencilDescriptor*   m_depthStencilDescriptor;
		MTL::StencilDescriptor*        m_frontFaceStencilDescriptor;
		MTL::StencilDescriptor*        m_backFaceStencilDescriptor;
		MTL::VertexDescriptor*         m_vertexDescriptor;
		MTL::SamplerDescriptor*        m_samplerDescriptor;

		MTL::Texture*             m_screenshotTarget;
		ShaderMtl                 m_screenshotBlitProgramVsh;
		ShaderMtl                 m_screenshotBlitProgramFsh;
		ProgramMtl                m_screenshotBlitProgram;
		MTL::RenderPipelineState* m_screenshotBlitRenderPipelineState;

		MTL::CommandBuffer*         m_commandBuffer;
		MTL::BlitCommandEncoder*    m_blitCommandEncoder;
		MTL::RenderCommandEncoder*  m_renderCommandEncoder;
		MTL::ComputeCommandEncoder* m_computeCommandEncoder;
		FrameBufferHandle           m_renderCommandEncoderFrameBufferHandle;
	};

	RendererContextI* rendererCreate(const Init& _init)
	{
		s_renderMtl = BX_NEW(g_allocator, RendererContextMtl);
		if (!s_renderMtl->init(_init) )
		{
			bx::deleteObject(g_allocator, s_renderMtl);
			s_renderMtl = NULL;
		}
		return s_renderMtl;
	}

	void rendererDestroy()
	{
		s_renderMtl->shutdown();
		bx::deleteObject(g_allocator, s_renderMtl);
		s_renderMtl = NULL;
	}

	void writeString(bx::WriterI* _writer, const char* _str)
	{
		bx::write(_writer, _str, (int32_t)bx::strLen(_str), bx::ErrorAssert{});
	}

	void ShaderMtl::create(const Memory* _mem)
	{
		bx::MemoryReader reader(_mem->data, _mem->size);

		bx::ErrorAssert err;

		uint32_t magic;
		bx::read(&reader, magic, &err);

		uint32_t hashIn;
		bx::read(&reader, hashIn, &err);

		uint32_t hashOut;

		if (isShaderVerLess(magic, 6) )
		{
			hashOut = hashIn;
		}
		else
		{
			bx::read(&reader, hashOut, &err);
		}

		uint16_t count;
		bx::read(&reader, count, &err);

		BX_TRACE("%s Shader consts %d"
			, getShaderTypeName(magic)
			, count
			);

		for (uint32_t ii = 0; ii < count; ++ii)
		{
			uint8_t nameSize;
			bx::read(&reader, nameSize, &err);

			char name[256];
			bx::read(&reader, &name, nameSize, &err);
			name[nameSize] = '\0';

			uint8_t type;
			bx::read(&reader, type, &err);

			uint8_t num;
			bx::read(&reader, num, &err);

			uint16_t regIndex;
			bx::read(&reader, regIndex, &err);

			uint16_t regCount;
			bx::read(&reader, regCount, &err);

			if (!isShaderVerLess(magic, 8) )
			{
				uint16_t texInfo = 0;
				bx::read(&reader, texInfo, &err);
			}

			if (!isShaderVerLess(magic, 10) )
			{
				uint16_t texFormat = 0;
				bx::read(&reader, texFormat, &err);
			}
		}

		if (isShaderType(magic, 'C') )
		{
			for (uint32_t ii = 0; ii < 3; ++ii)
			{
				bx::read(&reader, m_numThreads[ii], &err);
			}
		}

		uint32_t shaderSize;
		bx::read(&reader, shaderSize, &err);

		const char* code = (const char*)reader.getDataPtr();
		bx::skip(&reader, shaderSize+1);

		MTL::Library* lib = newLibraryWithSource(s_renderMtl->m_device, code);

		if (NULL != lib)
		{
			m_function = lib->newFunction(nsstr(SHADER_FUNCTION_NAME) );
			MTL_RELEASE_W(lib, 0);
		}

		BGFX_FATAL(NULL != m_function
			, bgfx::Fatal::InvalidShader
			, "Failed to create %s shader."
			, getShaderTypeName(magic)
			);

		bx::HashMurmur2A murmur;
		murmur.begin();
		murmur.add(hashIn);
		murmur.add(hashOut);
		murmur.add(code, shaderSize);
//		murmur.add(numAttrs);
//		murmur.add(m_attrMask, numAttrs);
		m_hash = murmur.end();
	}

	void ProgramMtl::create(const ShaderMtl* _vsh, const ShaderMtl* _fsh)
	{
		BX_ASSERT(NULL != _vsh->m_function, "Vertex shader doesn't exist.");
		m_vsh = _vsh;
		m_fsh = _fsh;

		// get attributes
		bx::memSet(m_attributes,   0xff, sizeof(m_attributes) );
		bx::memSet(m_instanceData, 0xff, sizeof(m_instanceData) );

		uint32_t used     = 0;
		uint32_t instUsed = 0;

		if (NULL != _vsh->m_function)
		{
			NS::Array* vertexAttribs = _vsh->m_function->vertexAttributes();

			for (NS::UInteger ai = 0, ac = vertexAttribs->count(); ai < ac; ++ai)
			{
				MTL::VertexAttribute* attrib = (MTL::VertexAttribute*)vertexAttribs->object(ai);

				if (attrib->isActive() )
				{
					const char* name = utf8String(attrib->name() );
					uint32_t loc = (uint32_t)attrib->attributeIndex();
					BX_TRACE("attr %s: %d", name, loc);

					for (uint8_t ii = 0; ii < Attrib::Count; ++ii)
					{
						if (0 == bx::strCmp(s_attribName[ii],name) )
						{
							m_attributes[ii] = loc;
							m_used[used++] = ii;
							break;
						}
					}

					for (uint32_t ii = 0; ii < BX_COUNTOF(s_instanceDataName); ++ii)
					{
						if (0 == bx::strCmp(s_instanceDataName[ii], name) )
						{
							m_instanceData[ii] = loc;
							instUsed = bx::max(instUsed, ii + 1);
							break;
						}
					}

				}
			}
		}

		m_used[used] = Attrib::Count;
		m_instanceData[instUsed] = UINT32_MAX;
	}

	void ProgramMtl::destroy()
	{
		m_vsh = NULL;
		m_fsh = NULL;
		if (NULL != m_computePS)
		{
			bx::deleteObject(g_allocator, m_computePS);
			m_computePS = NULL;
		}
	}

	void BufferMtl::create(uint32_t _size, void* _data, uint16_t _flags, uint16_t _stride, bool _vertex)
	{
		BX_UNUSED(_stride);

		m_size   = _size;
		m_flags  = _flags;
		m_vertex = _vertex;

		if (NULL == _data)
		{
			m_ptr = s_renderMtl->m_device->newBuffer(_size, MTL::ResourceCPUCacheModeDefaultCache);
		}
		else
		{
			m_ptr = s_renderMtl->m_device->newBuffer(_data, _size, MTL::ResourceCPUCacheModeDefaultCache);
		}
	}

	void BufferMtl::update(uint32_t _offset, uint32_t _size, void* _data, bool _discard)
	{
		MTL::BlitCommandEncoder* bce = s_renderMtl->getBlitCommandEncoder();

		if (!m_vertex
		&&  !_discard)
		{
			if (NULL == m_dynamic)
			{
				m_dynamic = (uint8_t*)bx::alloc(g_allocator, m_size);
			}

			bx::memCopy(m_dynamic + _offset, _data, _size);

			const uint32_t start = _offset & ~3;
			const uint32_t end   = bx::strideAlign(_offset + _size, 4);

			MTL::Buffer* temp = s_renderMtl->m_device->newBuffer(
				  m_dynamic + start
				, end - start
				, MTL::ResourceCPUCacheModeDefaultCache
				);

			bce->copyFromBuffer(temp, 0, m_ptr, start, end - start);

			s_renderMtl->m_cmd.release(temp);
		}
		else
		{
			MTL::Buffer* temp = s_renderMtl->m_device->newBuffer(_data, _size, MTL::ResourceCPUCacheModeDefaultCache);
			bce->copyFromBuffer(temp, 0, m_ptr, _offset, _size);
			s_renderMtl->m_cmd.release(temp);
		}
	}

	void VertexBufferMtl::create(uint32_t _size, void* _data, VertexLayoutHandle _layoutHandle, uint16_t _flags)
	{
		m_layoutHandle = _layoutHandle;
		uint16_t stride = isValid(_layoutHandle)
			? s_renderMtl->m_vertexLayouts[_layoutHandle.idx].m_stride
			: 0
			;

		BufferMtl::create(_size, _data, _flags, stride, true);
	}

	void TextureMtl::create(const Memory* _mem, uint64_t _flags, uint8_t _skip, uint64_t _external)
	{
		m_sampler = s_renderMtl->getSamplerState(uint32_t(_flags) );

		bimg::ImageContainer imageContainer;

		if (bimg::imageParse(imageContainer, _mem->data, _mem->size) )
		{
			const bimg::ImageBlockInfo& blockInfo = getBlockInfo(bimg::TextureFormat::Enum(imageContainer.m_format) );
			const uint8_t startLod = bx::min<uint8_t>(_skip, imageContainer.m_numMips-1);

			bimg::TextureInfo ti;
			bimg::imageGetSize(
				  &ti
				, uint16_t(imageContainer.m_width >>startLod)
				, uint16_t(imageContainer.m_height>>startLod)
				, uint16_t(imageContainer.m_depth >>startLod)
				, imageContainer.m_cubeMap
				, 1 < imageContainer.m_numMips
				, imageContainer.m_numLayers
				, imageContainer.m_format
				);
			ti.numMips = bx::min<uint8_t>(imageContainer.m_numMips-startLod, ti.numMips);

			m_flags  = _flags;
			m_width  = ti.width;
			m_height = ti.height;
			m_depth  = ti.depth;
			m_requestedFormat  = uint8_t(imageContainer.m_format);
			m_textureFormat    = uint8_t(getViableTextureFormat(imageContainer) );
			const bool convert = m_textureFormat != m_requestedFormat;
			const uint8_t bpp  = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(m_textureFormat) );

			MTL::TextureDescriptor* desc = newTextureDescriptor();

			if (1 < ti.numLayers)
			{
				if (imageContainer.m_cubeMap)
				{
					desc->setTextureType(MTL::TextureTypeCubeArray);
					m_type = TextureCube;
				}
				else
				{
					desc->setTextureType(MTL::TextureType2DArray);
					m_type = Texture2D;
				}
			}
			else if (imageContainer.m_cubeMap)
			{
				desc->setTextureType(MTL::TextureTypeCube);
				m_type = TextureCube;
			}
			else if (1 < imageContainer.m_depth)
			{
				desc->setTextureType(MTL::TextureType3D);
				m_type = Texture3D;
			}
			else
			{
				desc->setTextureType(MTL::TextureType2D);
				m_type = Texture2D;
			}

			m_numMips = ti.numMips;
			const uint16_t numSides = ti.numLayers * (imageContainer.m_cubeMap ? 6 : 1);
			const bool compressed   = bimg::isCompressed(bimg::TextureFormat::Enum(m_textureFormat) );
			const bool writeOnly    = 0 != (_flags&BGFX_TEXTURE_RT_WRITE_ONLY);
			const bool computeWrite = 0 != (_flags&BGFX_TEXTURE_COMPUTE_WRITE);
			const bool renderTarget = 0 != (_flags&BGFX_TEXTURE_RT_MASK);
			const bool srgb         = 0 != (_flags&BGFX_TEXTURE_SRGB);

			BX_TRACE("Texture %3d: %s (requested: %s), layers %d, %dx%d%s RT[%c], WO[%c], CW[%c], sRGB[%c]"
				, this - s_renderMtl->m_textures
				, getName( (TextureFormat::Enum)m_textureFormat)
				, getName( (TextureFormat::Enum)m_requestedFormat)
				, ti.numLayers
				, ti.width
				, ti.height
				, imageContainer.m_cubeMap ? "x6" : ""
				, renderTarget ? 'x' : ' '
				, writeOnly    ? 'x' : ' '
				, computeWrite ? 'x' : ' '
				, srgb         ? 'x' : ' '
				);

			const uint32_t msaaQuality = bx::satSub<uint32_t>(uint32_t( (_flags&BGFX_TEXTURE_RT_MSAA_MASK) >> BGFX_TEXTURE_RT_MSAA_SHIFT ), 1u);
			const int32_t  sampleCount = s_msaa[msaaQuality];

			const TextureFormatInfo& tfi = s_textureFormat[m_textureFormat];

			MTL::PixelFormat format = MTL::PixelFormatInvalid;
			if (srgb)
			{
				format = tfi.m_fmtSrgb;
				BX_WARN(format != MTL::PixelFormatInvalid
					, "sRGB not supported for texture format %d"
					, m_textureFormat
					);
			}

			if (format == MTL::PixelFormatInvalid)
			{
				// not swizzled and not sRGB, or sRGB unsupported
				format = tfi.m_fmt;
			}

			desc->setPixelFormat(format);
			desc->setWidth(ti.width);
			desc->setHeight(ti.height);
			desc->setDepth(bx::max(1,imageContainer.m_depth) );
			desc->setMipmapLevelCount(ti.numMips);
			desc->setSampleCount(1);
			desc->setArrayLength(ti.numLayers);
			desc->setSwizzle(*(MTL::TextureSwizzleChannels*)&tfi.m_mapping);

			if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
			{
				desc->setCpuCacheMode(MTL::CPUCacheModeDefaultCache);

				desc->setStorageMode(false
					|| writeOnly
					|| bimg::isDepth(bimg::TextureFormat::Enum(m_textureFormat) )
					?     MTL::StorageModePrivate
					: (BX_ENABLED(BX_PLATFORM_IOS) || BX_ENABLED(BX_PLATFORM_VISIONOS)
						? MTL::StorageModeShared
						: MTL::StorageModeManaged
					) );

				MTL::TextureUsage usage = 0
					|                 MTL::TextureUsageShaderRead
					| (computeWrite ? MTL::TextureUsageShaderWrite  : 0)
					| (renderTarget ? MTL::TextureUsageRenderTarget : 0)
					;

				desc->setUsage(usage);
			}

			if (0 != _external)
			{
				m_ptr    = (MTL::Texture*)(void*)_external;
				m_flags |= BGFX_SAMPLER_INTERNAL_SHARED;
			}
			else
			{
				m_ptr = s_renderMtl->m_device->newTexture(desc);
			}

			if (sampleCount > 1)
			{
				desc->setTextureType(MTL::TextureType2DMultisample);
				desc->setSampleCount(sampleCount);
				desc->setMipmapLevelCount(1);

				if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
				{
					desc->setStorageMode(MTL::StorageModePrivate);
				}

				m_ptrMsaa = s_renderMtl->m_device->newTexture(desc);
			}

			if (m_requestedFormat == TextureFormat::D24S8
			&&  desc->pixelFormat() == MTL::PixelFormatDepth32Float)
			{
				desc->setPixelFormat(MTL::PixelFormatStencil8);
				m_ptrStencil = s_renderMtl->m_device->newTexture(desc);
			}

			uint8_t* temp = NULL;
			if (convert)
			{
				temp = (uint8_t*)bx::alloc(g_allocator, ti.width*ti.height*4);
			}

			for (uint16_t side = 0; side < numSides; ++side)
			{
				uint32_t width  = ti.width;
				uint32_t height = ti.height;
				uint32_t depth  = ti.depth;

				for (uint8_t lod = 0, num = ti.numMips; lod < num; ++lod)
				{
					width  = bx::max(1u, width);
					height = bx::max(1u, height);
					depth  = bx::max(1u, depth);

					bimg::ImageMip mip;
					if (bimg::imageGetRawData(imageContainer, side, lod+startLod, _mem->data, _mem->size, mip) )
					{
						const uint8_t* data = mip.m_data;

						if (convert)
						{
							bimg::imageDecodeToBgra8(
								  g_allocator
								, temp
								, mip.m_data
								, mip.m_width
								, mip.m_height
								, mip.m_width*4
								, mip.m_format
								);
							data = temp;
						}

						MTL::Region region(0, 0, 0, width, height, depth);

						uint32_t bytesPerRow   = 0;
						uint32_t bytesPerImage = 0;

						if (compressed && !convert)
						{
							if (format >= 160 /*PVRTC_RGB_2BPP*/
							&&  format <= 167 /*PVRTC_RGBA_4BPP_sRGB*/)
							{
								bytesPerRow   = 0;
								bytesPerImage = 0;
							}
							else
							{
								bytesPerRow   = (mip.m_width / blockInfo.blockWidth)*mip.m_blockSize;
								bytesPerImage = desc->textureType() == MTL::TextureType3D
									? (mip.m_height/blockInfo.blockHeight)*bytesPerRow
									: 0
									;
							}
						}
						else
						{
							bytesPerRow   = width * bpp / 8;
							bytesPerImage = desc->textureType() == MTL::TextureType3D
								? bytesPerRow * height
								: 0
								;
						}

						m_ptr->replaceRegion(region, lod, side, data, bytesPerRow, bytesPerImage);
					}

					width  >>= 1;
					height >>= 1;
					depth  >>= 1;
				}
			}

			MTL_RELEASE(desc, 0);

			if (NULL != temp)
			{
				bx::free(g_allocator, temp);
			}
		}
	}

	void TextureMtl::destroy()
	{
		if (0 == (m_flags & BGFX_SAMPLER_INTERNAL_SHARED) )
		{
			MTL_RELEASE_W(m_ptr, 0);
		}

		MTL_RELEASE_W(m_ptrMsaa, 0);
		MTL_RELEASE_W(m_ptrStencil, 0);

		for (uint32_t ii = 0; ii < m_numMips; ++ii)
		{
			MTL_RELEASE_W(m_ptrMips[ii], 0);
		}
	}

	void TextureMtl::overrideInternal(uintptr_t _ptr)
	{
		destroy();
		m_flags |= BGFX_SAMPLER_INTERNAL_SHARED;
		m_ptr = (MTL::Texture*)(void*)_ptr;
	}

	void TextureMtl::update(uint8_t _side, uint8_t _mip, const Rect& _rect, uint16_t _z, uint16_t _depth, uint16_t _pitch, const Memory* _mem)
	{
		const uint32_t bpp       = bimg::getBitsPerPixel(bimg::TextureFormat::Enum(m_textureFormat) );
		uint32_t rectpitch  = _rect.m_width*bpp/8;
		if (bimg::isCompressed(bimg::TextureFormat::Enum(m_textureFormat) ) )
		{
			if (m_ptr->pixelFormat() >= 160 /*PVRTC_RGB_2BPP*/
			&&  m_ptr->pixelFormat() <= 167 /*PVRTC_RGBA_4BPP_sRGB*/)
			{
				rectpitch   = 0;
			}
			else
			{
				const bimg::ImageBlockInfo& blockInfo = bimg::getBlockInfo(bimg::TextureFormat::Enum(m_textureFormat) );
				rectpitch = (_rect.m_width / blockInfo.blockWidth)*blockInfo.blockSize;
			}
		}
		const uint32_t srcpitch  = UINT16_MAX == _pitch ? rectpitch : _pitch;
		const uint32_t slice     = ( (m_type == Texture3D) ? 0 : _side + _z * (m_type == TextureCube ? 6 : 1) );
		const uint16_t zz        = (m_type == Texture3D) ? _z : 0 ;

		const uint32_t mipWidth  = bx::max(1u, uint32_t(m_width)  >> _mip);
		const uint32_t mipHeight = bx::max(1u, uint32_t(m_height) >> _mip);
		const uint32_t width     = bx::min<uint32_t>(_rect.m_width,  mipWidth);
		const uint32_t height    = bx::min<uint32_t>(_rect.m_height, mipHeight);

		const bool convert = m_textureFormat != m_requestedFormat;

		uint8_t* data = _mem->data;
		uint8_t* temp = NULL;

		if (convert)
		{
			temp = (uint8_t*)bx::alloc(g_allocator, rectpitch*_rect.m_height);
			bimg::imageDecodeToBgra8(
				  g_allocator
				, temp
				, data
				, _rect.m_width
				, _rect.m_height
				, srcpitch
				, bimg::TextureFormat::Enum(m_requestedFormat)
				);
			data = temp;
		}

		if (NULL != s_renderMtl->m_renderCommandEncoder)
		{
			s_renderMtl->m_cmd.finish(true);

			MTL::Region region(_rect.m_x, _rect.m_y, zz, width, height, _depth);

			m_ptr->replaceRegion(region, _mip, slice, data, srcpitch, srcpitch * _rect.m_height);
		}
		else
		{
			MTL::BlitCommandEncoder* bce = s_renderMtl->getBlitCommandEncoder();

			MTL::TextureDescriptor* desc = newTextureDescriptor();
			desc->setTextureType(_depth > 1 ? MTL::TextureType3D : MTL::TextureType2D);
			desc->setPixelFormat(m_ptr->pixelFormat() );
			desc->setWidth(width);
			desc->setHeight(height);
			desc->setDepth(_depth);
			desc->setMipmapLevelCount(1);
			desc->setSampleCount(1);
			desc->setArrayLength(1);

			if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
			{
				desc->setCpuCacheMode(MTL::CPUCacheModeDefaultCache);
				desc->setStorageMode(BX_ENABLED(BX_PLATFORM_IOS) || BX_ENABLED(BX_PLATFORM_VISIONOS)
					? MTL::StorageModeShared
					: MTL::StorageModeManaged)
					;
				desc->setUsage(MTL::TextureUsage(0) );
			}

			MTL::Texture* tempTexture = s_renderMtl->m_device->newTexture(desc);

			MTL::Region region(0, 0, 0, width, height, _depth);

			tempTexture->replaceRegion(region, 0, 0, data, srcpitch, srcpitch * _rect.m_height);

			bce->copyFromTexture(
				  tempTexture
				, 0
				, 0
				, MTL::Origin::Make(0,0,0)
				, MTL::Size::Make(width, height, _depth)
				, m_ptr
				, slice
				, _mip
				, MTL::Origin::Make(_rect.m_x, _rect.m_y, zz)
				);

			MTL_RELEASE(desc, 0);
			MTL_RELEASE(tempTexture, 1);
		}

		if (NULL != temp)
		{
			bx::free(g_allocator, temp);
		}
	}

	void TextureMtl::commit(uint8_t _stage, bool _vertex, bool _fragment, uint32_t _flags, uint8_t _mip)
	{
		if (_vertex)
		{
			MTL::Texture* p = _mip != UINT8_MAX ? getTextureMipLevel(_mip) : m_ptr;
			s_renderMtl->m_renderCommandEncoder->setVertexTexture(p, _stage);
			s_renderMtl->m_renderCommandEncoder->setVertexSamplerState(
				  0 == (BGFX_SAMPLER_INTERNAL_DEFAULT & _flags)
					? s_renderMtl->getSamplerState(_flags)
					: m_sampler
				, _stage
				);
		}

		if (_fragment)
		{
			MTL::Texture* p = _mip != UINT8_MAX ? getTextureMipLevel(_mip) : m_ptr;
			s_renderMtl->m_renderCommandEncoder->setFragmentTexture(p, _stage);
			s_renderMtl->m_renderCommandEncoder->setFragmentSamplerState(
				  0 == (BGFX_SAMPLER_INTERNAL_DEFAULT & _flags)
					? s_renderMtl->getSamplerState(_flags)
					: m_sampler
				, _stage
				);
		}
	}

	MTL::Texture* TextureMtl::getTextureMipLevel(uint8_t _mip)
	{
		_mip = bx::clamp(_mip, 0, m_numMips);

		if (NULL != m_ptr)
		{
			if (NULL == m_ptrMips[_mip])
			{
				if (TextureCube == m_type)
				{
					m_ptrMips[_mip] = m_ptr->newTextureView(
						  m_ptr->pixelFormat()
						, (MTL::TextureType)MTL::TextureType2DArray
						, NS::Range::Make(_mip, 1)
						, NS::Range::Make(0, m_ptr->arrayLength() * 6)
						);
				}
				else
				{
					m_ptrMips[_mip] = m_ptr->newTextureView(
						  m_ptr->pixelFormat()
						, m_ptr->textureType()
						, NS::Range::Make(_mip, 1)
						, NS::Range::Make(0, m_ptr->arrayLength() )
						);
				}
			}

			return m_ptrMips[_mip];
		}

		return NULL;
	}

	SwapChainMtl::~SwapChainMtl()
	{
		MTL_RELEASE(m_metalLayer, 2);
		MTL_RELEASE(m_drawable, 0);

		MTL_RELEASE(m_drawableTexture, 0);

		releaseBackBuffer();
	}

	void SwapChainMtl::init(void* _nwh)
	{
		{
			MTL_RELEASE(m_metalLayer, 2);

			Class mtkViewClass = objc_lookUpClass("MTKView");
			if (NULL != mtkViewClass)
			{
				if (NULL != _nwh
				&&  MtlObjAccess::send<bool>(_nwh, sel_registerName("isKindOfClass:"), mtkViewClass) )
				{
					m_metalLayer = (CA::MetalLayer*)MtlObjAccess::send<void*>(_nwh, sel_registerName("layer") );
				}
			}

			Class caMetalLayerClass = objc_lookUpClass("CAMetalLayer");
			if (NULL != caMetalLayerClass)
			{
				if (NULL == m_metalLayer)
#	if BX_PLATFORM_IOS || BX_PLATFORM_VISIONOS
				{
					CA::MetalLayer* metalLayer = (CA::MetalLayer*)_nwh;

					if (NULL == metalLayer
					||  !MtlObjAccess::send<bool>(metalLayer, sel_registerName("isKindOfClass:"), caMetalLayerClass) )
					{
						BX_WARN(false, "Unable to create Metal device. Please set platform data window to a CAMetalLayer");
						return;
					}

					m_metalLayer = metalLayer;
				}
#	elif BX_PLATFORM_OSX
				{
					if (MtlObjAccess::send<bool>(_nwh, sel_registerName("isKindOfClass:"), caMetalLayerClass) )
					{
						m_metalLayer = (CA::MetalLayer*)_nwh;
					}
					else
					{
						void* contentView = NULL;

						Class nsViewClass   = objc_lookUpClass("NSView");
						Class nsWindowClass = objc_lookUpClass("NSWindow");

						if (MtlObjAccess::send<bool>(_nwh, sel_registerName("isKindOfClass:"), nsViewClass) )
						{
							contentView = _nwh;
						}
						else if (MtlObjAccess::send<bool>(_nwh, sel_registerName("isKindOfClass:"), nsWindowClass) )
						{
							contentView = MtlObjAccess::send<void*>(_nwh, sel_registerName("contentView") );
						}
						else
						{
							BX_WARN(0, "Unable to create Metal device. Please set platform data window to an NSWindow, NSView, or CAMetalLayer");
							return;
						}

						void (^setLayer)(void) =
						^{
							void* layer = MtlObjAccess::send<void*>(contentView, sel_registerName("layer") );

							if(NULL != layer && MtlObjAccess::send<bool>(layer, sel_registerName("isKindOfClass:"), caMetalLayerClass) )
							{
								m_metalLayer = (CA::MetalLayer*)layer;
							}
							else
							{
								MtlObjAccess::send<void>(contentView, sel_registerName("setWantsLayer:"), true);
								m_metalLayer = CA::MetalLayer::layer();
								MtlObjAccess::send<void>(contentView, sel_registerName("setLayer:"), m_metalLayer);
							}
						};

						Class nsThreadClass = objc_lookUpClass("NSThread");
						if (MtlObjAccess::send<bool>(nsThreadClass, sel_registerName("isMainThread") ) )
						{
							setLayer();
						}
						else
						{
							bx::Semaphore semaphore;
							bx::Semaphore* psemaphore = &semaphore;

							Class nsRunLoopClass = objc_lookUpClass("NSRunLoop");
							void* mainRunLoop = MtlObjAccess::send<void*>(nsRunLoopClass, sel_registerName("mainRunLoop") );
							CFRunLoopRef cfRunLoop = MtlObjAccess::send<CFRunLoopRef>(mainRunLoop, sel_registerName("getCFRunLoop") );

							CFRunLoopPerformBlock(cfRunLoop, kCFRunLoopCommonModes,
							^{
								setLayer();
								psemaphore->post();
							});

							semaphore.wait();
						}
					}
				}
#	endif // BX_PLATFORM_*
			}

			if (NULL == m_metalLayer)
			{
				BX_WARN(NULL != s_renderMtl->m_device, "Unable to create Metal device.");
				return;
			}

			m_metalLayer->setDevice(s_renderMtl->m_device);
			MtlObjAccess::send<void>(m_metalLayer, sel_registerName("setMagnificationFilter:"), nsstr("nearest") );

			const Resolution& resolution = s_renderMtl->m_resolution;
			m_metalLayer->setPixelFormat( (MTL::PixelFormat)( (resolution.reset & BGFX_RESET_SRGB_BACKBUFFER)
				? s_textureFormat[resolution.formatColor].m_fmtSrgb
				: s_textureFormat[resolution.formatColor].m_fmt) )
				;

			retain(m_metalLayer);
		}

		m_nwh = _nwh;
	}

	void SwapChainMtl::releaseBackBuffer()
	{
		MTL_RELEASE(m_backBufferStencil, m_backBufferDepth == m_backBufferStencil ? 1 : 0);
		MTL_RELEASE_W(m_backBufferDepth, 0);
		MTL_RELEASE_W(m_backBufferColorMsaa, 0);
	}

	uint32_t SwapChainMtl::resize(uint32_t _width, uint32_t _height, TextureFormat::Enum _format, TextureFormat::Enum _depthFormat)
	{
		releaseBackBuffer();

		const Resolution& resolution   = s_renderMtl->m_resolution;

		const uint32_t resetFlags      = resolution.reset;
		const uint32_t maxFrameLatency = resolution.maxFrameLatency;
		const TextureFormat::Enum formatColor = TextureFormat::Count == _format
			? resolution.formatColor
			: _format
			;
		const TextureFormat::Enum formatDepthStencil = TextureFormat::Count == _depthFormat
			? resolution.formatDepthStencil
			: _depthFormat
			;

		const int32_t sampleCount = s_msaa[(resetFlags & BGFX_RESET_MSAA_MASK)>>BGFX_RESET_MSAA_SHIFT];

#if BX_PLATFORM_OSX
#	if __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
		if (s_renderMtl->m_hasVSync)
		{
			m_metalLayer->setDisplaySyncEnabled(!!(resetFlags & BGFX_RESET_VSYNC) );
		}

		if (s_renderMtl->m_hasMaximumDrawableCount)
		{
			m_metalLayer->setMaximumDrawableCount(bx::clamp<uint32_t>(
				  maxFrameLatency != 0 ? maxFrameLatency : BGFX_CONFIG_MAX_FRAME_LATENCY
				, 2
				, 3
				) );
		}
#	endif // __MAC_OS_X_VERSION_MAX_ALLOWED >= 101300
#endif // BX_PLATFORM_OSX

		{
			m_metalLayer->setDrawableSize(CGSizeMake(_width, _height) );
			m_metalLayer->setPixelFormat( (MTL::PixelFormat)( (resetFlags & BGFX_RESET_SRGB_BACKBUFFER)
				? s_textureFormat[formatColor].m_fmtSrgb
				: s_textureFormat[formatColor].m_fmt) )
				;

			const CGSize actualSize = m_metalLayer->drawableSize();
			BX_WARN(true
				&& uint32_t(actualSize.width)  == _width
				&& uint32_t(actualSize.height) == _height
				, "CAMetalLayer drawableSize is %ux%u after requesting %ux%u. "
				  "The host layer (MTKView? with autoReizeDrawable=YES) "
				  "is overriding the size requested via bgfx::init/reset. "
				  "Either disable host auto-resizable, or pass the post-layout "
				  "drawable size to bgfx."
				, uint32_t(actualSize.width)
				, uint32_t(actualSize.height)
				, _width
				, _height
				);
		}

		MTL::TextureDescriptor* desc = newTextureDescriptor();

		desc->setTextureType(sampleCount > 1
			? MTL::TextureType2DMultisample
			: MTL::TextureType2D)
			;

		desc->setWidth(_width);
		desc->setHeight(_height);
		desc->setDepth(1);
		desc->setMipmapLevelCount(1);
		desc->setSampleCount(sampleCount);
		desc->setArrayLength(1);
		MTL::TextureSwizzleChannels defaultSwizzle(MTL::TextureSwizzleRed, MTL::TextureSwizzleGreen, MTL::TextureSwizzleBlue, MTL::TextureSwizzleAlpha);
		desc->setSwizzle(defaultSwizzle);

		if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
		{
			desc->setCpuCacheMode(MTL::CPUCacheModeDefaultCache);
			desc->setStorageMode(MTL::StorageModePrivate);
			desc->setUsage(MTL::TextureUsageRenderTarget);
		}

		if (bimg::isDepth(bimg::TextureFormat::Enum(formatDepthStencil) ) )
		{
			const MTL::PixelFormat depthFormat = s_textureFormat[formatDepthStencil].m_fmt;

			{
				desc->setPixelFormat(depthFormat);
				m_backBufferDepth = s_renderMtl->m_device->newTexture(desc);
			}

			if (MTL::PixelFormatDepth24Unorm_Stencil8 == depthFormat
			||  MTL::PixelFormatDepth32Float_Stencil8 == depthFormat)
			{
				m_backBufferDepth->setLabel(nsstr("SwapChain BackBuffer Depth/Stencil") );

				m_backBufferStencil = m_backBufferDepth;
				retain(m_backBufferStencil);
			}
			else
			{
				m_backBufferDepth->setLabel(nsstr("SwapChain BackBuffer Depth") );

				desc->setPixelFormat(MTL::PixelFormatStencil8);

				m_backBufferStencil = s_renderMtl->m_device->newTexture(desc);
				m_backBufferStencil->setLabel(nsstr("SwapChain BackBuffer Stencil") );
			}
		}

		if (sampleCount > 1)
		{
			desc->setPixelFormat(m_metalLayer->pixelFormat() );
			m_backBufferColorMsaa = s_renderMtl->m_device->newTexture(desc);
			m_backBufferColorMsaa->setLabel(nsstr("SwapChain BackBuffer Color MSAA") );
		}

		MTL_RELEASE(desc, 0);

		bx::HashMurmur2A murmur;
		murmur.begin();
		murmur.add(1);
		murmur.add(m_metalLayer->pixelFormat() );
		murmur.add(formatColor);
		murmur.add(formatDepthStencil);
		murmur.add(sampleCount);

		return murmur.end();
	}

	MTL::Texture* SwapChainMtl::currentDrawableTexture()
	{
		if (NULL == m_drawableTexture)
		{
			m_drawable = m_metalLayer->nextDrawable();

			if (m_drawable != NULL)
			{
				m_drawableTexture = m_drawable->texture();
				retain(m_drawable); // keep alive to be usable at 'flip'
				retain(m_drawableTexture);
			}
			else
			{
				MTL::TextureDescriptor* desc = newTextureDescriptor();
				desc->setTextureType(MTL::TextureType2D);

				desc->setPixelFormat(m_metalLayer->pixelFormat() );
				desc->setWidth(m_metalLayer->drawableSize().width);
				desc->setHeight(m_metalLayer->drawableSize().height);

				desc->setDepth(1);
				desc->setMipmapLevelCount(1);
				desc->setSampleCount(1);
				desc->setArrayLength(1);

				if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
				{
					desc->setCpuCacheMode(MTL::CPUCacheModeDefaultCache);
					desc->setStorageMode(BX_ENABLED(BX_PLATFORM_IOS) || BX_ENABLED(BX_PLATFORM_VISIONOS)
						? MTL::StorageModeShared
						: MTL::StorageModeManaged)
						;

					desc->setUsage(MTL::TextureUsageRenderTarget);
				}

				m_drawableTexture = s_renderMtl->m_device->newTexture(desc);
				MTL_CHECK_REFCOUNT(m_drawableTexture, 1);
				MTL_RELEASE(desc, 0);
			}
		}

		return m_drawableTexture;
	}

	void FrameBufferMtl::create(uint8_t _num, const Attachment* _attachment)
	{
		m_swapChain = NULL;
		m_denseIdx  = UINT16_MAX;
		m_num       = 0;
		m_width     = 0;
		m_height    = 0;

		for (uint32_t ii = 0; ii < _num; ++ii)
		{
			const Attachment& at = _attachment[ii];
			TextureHandle handle = at.handle;

			if (isValid(handle) )
			{
				const TextureMtl& texture = s_renderMtl->m_textures[handle.idx];

				if (0 == m_width)
				{
					m_width = texture.m_width;
					m_height = texture.m_height;
				}

				if (bimg::isDepth(bimg::TextureFormat::Enum(texture.m_textureFormat) ) )
				{
					m_depthHandle = handle;
					m_depthAttachment = at;
				}
				else
				{
					m_colorHandle[m_num] = handle;
					m_colorAttachment[m_num] = at;
					m_num++;
				}
			}
		}

		bx::HashMurmur2A murmur;
		murmur.begin();
		murmur.add(m_num);

		for (uint32_t ii = 0; ii < m_num; ++ii)
		{
			const TextureMtl& texture = s_renderMtl->m_textures[m_colorHandle[ii].idx];
			murmur.add(uint32_t(texture.m_ptr->pixelFormat() ) );
		}

		if (!isValid(m_depthHandle) )
		{
			murmur.add(uint32_t(MTL::PixelFormatInvalid) );
			murmur.add(uint32_t(MTL::PixelFormatInvalid) );
		}
		else
		{
			const TextureMtl& depthTexture = s_renderMtl->m_textures[m_depthHandle.idx];
			murmur.add(uint32_t(depthTexture.m_ptr->pixelFormat() ) );
			murmur.add(NULL != depthTexture.m_ptrStencil
				? depthTexture.m_ptrStencil->pixelFormat()
				: MTL::PixelFormatInvalid
				);
		}

		const TextureMtl &firstTexture = s_renderMtl->m_textures[_attachment[0].handle.idx];
		const uint32_t msaaQuality = bx::satSub<uint32_t>(uint32_t( (firstTexture.m_flags&BGFX_TEXTURE_RT_MSAA_MASK) >> BGFX_TEXTURE_RT_MSAA_SHIFT ), 1u);
		const int32_t sampleCount = s_msaa[msaaQuality];
		murmur.add(sampleCount);

		m_pixelFormatHash = murmur.end();
	}

	void FrameBufferMtl::create(uint16_t _denseIdx, void* _nwh, uint32_t _width, uint32_t _height, TextureFormat::Enum _format, TextureFormat::Enum _depthFormat)
	{
		BX_UNUSED(_format, _depthFormat);
		m_swapChain = BX_NEW(g_allocator, SwapChainMtl);
		m_num       = 0;
		m_width     = _width;
		m_height    = _height;
		m_nwh       = _nwh;
		m_denseIdx  = _denseIdx;

		m_swapChain->init(_nwh);
		resizeSwapChain(_width, _height, _format, _depthFormat);
	}

	void FrameBufferMtl::postReset()
	{
	}

	uint16_t FrameBufferMtl::destroy()
	{
		if (NULL != m_swapChain)
		{
			bx::deleteObject(g_allocator, m_swapChain);
			m_swapChain = NULL;
		}

		m_num = 0;
		m_nwh = NULL;
		m_depthHandle = BGFX_INVALID_HANDLE;

		uint16_t denseIdx = m_denseIdx;
		m_denseIdx = UINT16_MAX;

		return denseIdx;
	}

	void FrameBufferMtl::resolve()
	{
		for (uint32_t ii = 0; ii < m_num; ++ii)
		{
			if (0 != (m_colorAttachment[ii].resolve & BGFX_RESOLVE_AUTO_GEN_MIPS) )
			{
				const TextureMtl& texture = s_renderMtl->m_textures[m_colorHandle[ii].idx];
				const bool isRenderTarget = !!(texture.m_flags & BGFX_TEXTURE_RT_MASK);
				const bool hasMips        = 1 < texture.m_numMips;
				const bool fmtSupport     = 0 != (g_caps.formats[texture.m_textureFormat] & BGFX_CAPS_FORMAT_TEXTURE_MIP_AUTOGEN);

				if (isRenderTarget
				&&  fmtSupport
				&&  hasMips)
				{
					MTL::BlitCommandEncoder* bce = s_renderMtl->getBlitCommandEncoder();
					bce->generateMipmaps(texture.m_ptr);
				}
			}
		}

		s_renderMtl->endEncoding();
	}

	void FrameBufferMtl::resizeSwapChain(uint32_t _width, uint32_t _height, TextureFormat::Enum _format, TextureFormat::Enum _depthFormat)
	{
		m_pixelFormatHash = m_swapChain->resize(_width, _height, _format, _depthFormat);
	}

	void CommandQueueMtl::init(MTL::Device* _device, uint32_t _maxFrameLatency)
	{
		m_commandQueue = _device->newCommandQueue();
		m_maxFrameLatency = bx::min<uint32_t>(
			  _maxFrameLatency != 0 ? _maxFrameLatency : BGFX_CONFIG_MAX_FRAME_LATENCY
			, BGFX_CONFIG_MAX_FRAME_LATENCY
			);
		m_framesSemaphore.post(m_maxFrameLatency);
	}

	void CommandQueueMtl::shutdown()
	{
		finish(true);

		{
			NS::AutoreleasePool* pool = NS::AutoreleasePool::alloc()->init();

			MTL_RELEASE(m_commandQueue, 0);

			pool->release();
		}
	}

	MTL::CommandBuffer* CommandQueueMtl::alloc()
	{
		{
			NS::AutoreleasePool* pool = NS::AutoreleasePool::alloc()->init();

			m_activeCommandBuffer = m_commandQueue->commandBuffer();
			retain(m_activeCommandBuffer);

			pool->release();
		}
		return m_activeCommandBuffer;
	}

	inline void commandBufferFinishedCallback(void* _data)
	{
		CommandQueueMtl* queue = (CommandQueueMtl*)_data;

		if (queue)
		{
			queue->m_framesSemaphore.post();
		}
	}

	void CommandQueueMtl::kick(bool _endFrame, bool _waitForFinish)
	{
		if (m_activeCommandBuffer)
		{
			if (_endFrame)
			{
				m_releaseWriteIndex = (m_releaseWriteIndex + 1) % BGFX_CONFIG_MAX_FRAME_LATENCY;
				m_activeCommandBuffer->addCompletedHandler(
					MTL::HandlerFunction([this](MTL::CommandBuffer*) { commandBufferFinishedCallback(this); })
					);
			}

			m_activeCommandBuffer->commit();

			if (_waitForFinish)
			{
				m_activeCommandBuffer->waitUntilCompleted();
			}

			{
				NS::AutoreleasePool* pool = NS::AutoreleasePool::alloc()->init();

				MTL_RELEASE_I(m_activeCommandBuffer);

				pool->release();
			}
		}
	}

	void CommandQueueMtl::finish(bool _finishAll)
	{
		if (_finishAll)
		{
			const uint32_t count = m_activeCommandBuffer != NULL
				? m_maxFrameLatency - 1
				: m_maxFrameLatency
				;

			for (uint32_t ii = 0; ii < count; ++ii)
			{
				consume();
			}

			m_framesSemaphore.post(count);
		}
		else
		{
			consume();
		}
	}

	void CommandQueueMtl::release(NS::Object* _ptr)
	{
		m_release[m_releaseWriteIndex].push_back(_ptr);
	}

	void CommandQueueMtl::consume()
	{
		m_framesSemaphore.wait();
		m_releaseReadIndex = (m_releaseReadIndex + 1) % BGFX_CONFIG_MAX_FRAME_LATENCY;

		ResourceArray& ra = m_release[m_releaseReadIndex];

		for (ResourceArray::iterator it = ra.begin(), itEnd = ra.end(); it != itEnd; ++it)
		{
			MTL_RELEASE_I(*it);
		}

		ra.clear();
	}

	void TimerQueryMtl::init()
	{
		m_frequency = bx::getHPFrequency();
	}

	void TimerQueryMtl::shutdown()
	{
	}

	uint32_t TimerQueryMtl::begin(uint32_t _resultIdx, uint32_t _frameNum)
	{
		BX_UNUSED(_resultIdx);
		BX_UNUSED(_frameNum);
		return 0;
	}

	void TimerQueryMtl::end(uint32_t _idx)
	{
		BX_UNUSED(_idx);
	}

	static void setTimestamp(void* _data)
	{
		*( (int64_t*)_data) = bx::getHPCounter();
	}

	void TimerQueryMtl::addHandlers(MTL::CommandBuffer*& _commandBuffer)
	{
		while (0 == m_control.reserve(1) )
		{
			m_control.consume(1);
		}

		uint32_t offset = m_control.m_current;

		_commandBuffer->addScheduledHandler(
			MTL::HandlerFunction([pBegin = &m_result[offset].m_begin](MTL::CommandBuffer*) { setTimestamp(pBegin); })
			);
		_commandBuffer->addCompletedHandler(
			MTL::HandlerFunction([pEnd = &m_result[offset].m_end](MTL::CommandBuffer*) { setTimestamp(pEnd); })
			);
		m_control.commit(1);
	}

	bool TimerQueryMtl::get()
	{
		if (0 != m_control.getNumUsed() )
		{
			uint32_t offset = m_control.m_read;
			m_begin = m_result[offset].m_begin;
			m_end   = m_result[offset].m_end;
			m_elapsed = m_end - m_begin;

			m_control.consume(1);

			return true;
		}

		return false;
	}

	void OcclusionQueryMTL::postReset()
	{
		MTL_RELEASE_W(m_buffer, 0);
	}

	void OcclusionQueryMTL::preReset()
	{
		m_buffer = s_renderMtl->m_device->newBuffer(BX_COUNTOF(m_query) * 8, MTL::ResourceCPUCacheModeDefaultCache);
	}

	void OcclusionQueryMTL::begin(MTL::RenderCommandEncoder*& _rce, Frame* _render, OcclusionQueryHandle _handle)
	{
		while (0 == m_control.reserve(1) )
		{
			resolve(_render, true);
		}

		Query& query = m_query[m_control.m_current];
		query.m_handle  = _handle;
		uint32_t offset = _handle.idx * 8;
		_rce->setVisibilityResultMode( (MTL::VisibilityResultMode)MTL::VisibilityResultModeBoolean, offset);
	}

	void OcclusionQueryMTL::end(MTL::RenderCommandEncoder*& _rce)
	{
		Query& query = m_query[m_control.m_current];
		uint32_t offset = query.m_handle.idx * 8;
		_rce->setVisibilityResultMode( (MTL::VisibilityResultMode)MTL::VisibilityResultModeDisabled, offset);
		m_control.commit(1);
	}

	void OcclusionQueryMTL::resolve(Frame* _render, bool _wait)
	{
		BX_UNUSED(_wait);

		while (0 != m_control.getNumUsed() )
		{
			Query& query = m_query[m_control.m_read];

			if (isValid(query.m_handle) )
			{
				uint64_t result = ( (uint64_t*)m_buffer->contents() )[query.m_handle.idx];
				_render->m_occlusion[query.m_handle.idx] = int32_t(result);
			}

			m_control.consume(1);
		}
	}

	void OcclusionQueryMTL::invalidate(OcclusionQueryHandle _handle)
	{
		const uint32_t size = m_control.m_size;

		for (uint32_t ii = 0, num = m_control.getNumUsed(); ii < num; ++ii)
		{
			Query& query = m_query[(m_control.m_read + ii) % size];
			if (query.m_handle.idx == _handle.idx)
			{
				query.m_handle.idx = bgfx::kInvalidHandle;
			}
		}
	}

	void RendererContextMtl::submitBlit(BlitState& _bs, uint16_t _view)
	{
		if (!_bs.hasItem(_view) )
		{
			return;
		}

		endEncoding();

		m_blitCommandEncoder = getBlitCommandEncoder();

		while (_bs.hasItem(_view) )
		{
			const BlitItem& blit = _bs.advance();

			const TextureMtl& src = m_textures[blit.m_src.idx];
			const TextureMtl& dst = m_textures[blit.m_dst.idx];

#if BX_PLATFORM_OSX
			const bool readBack = !!(dst.m_flags & BGFX_TEXTURE_READ_BACK);
#endif  // BX_PLATFORM_OSX

			if (MTL::TextureType3D == src.m_ptr->textureType() )
			{
				m_blitCommandEncoder->copyFromTexture(
					  src.m_ptr
					, 0
					, 0
					, MTL::Origin::Make(blit.m_srcX, blit.m_srcY, blit.m_srcZ)
					, MTL::Size::Make(blit.m_width, blit.m_height, bx::max<int32_t>(blit.m_depth, 1) )
					, dst.m_ptr
					, 0
					, 0
					, MTL::Origin::Make(blit.m_dstX, blit.m_dstY, blit.m_dstZ)
					);
#if BX_PLATFORM_OSX
				if (m_hasSynchronizeResource && readBack)
				{
					m_blitCommandEncoder->synchronizeResource(dst.m_ptr);
				}
#endif  // BX_PLATFORM_OSX
			}
			else
			{
				m_blitCommandEncoder->copyFromTexture(
					  src.m_ptr
					, blit.m_srcZ
					, blit.m_srcMip
					, MTL::Origin::Make(blit.m_srcX, blit.m_srcY, 0)
					, MTL::Size::Make(blit.m_width, blit.m_height, 1)
					, dst.m_ptr
					, blit.m_dstZ
					, blit.m_dstMip
					, MTL::Origin::Make(blit.m_dstX, blit.m_dstY, 0)
					);
#if BX_PLATFORM_OSX
				if (m_hasSynchronizeResource && readBack)
				{
					m_blitCommandEncoder->synchronizeTexture(dst.m_ptr, 0, blit.m_dstMip);
				}
#endif  // BX_PLATFORM_OSX
			}
		}

		if (0 != m_blitCommandEncoder)
		{
			m_blitCommandEncoder->endEncoding();
			m_blitCommandEncoder = 0;
		}
	}

	void RendererContextMtl::submitUniformCache(UniformCacheState& _ucs, uint16_t _view)
	{
		while (_ucs.hasItem(_view) )
		{
			const UniformCacheItem& uci = _ucs.advance();

			bx::memCopy(m_uniforms[uci.m_handle], &_ucs.m_frame->m_uniformCacheFrame.m_data[uci.m_offset], uci.m_size);
		}
	}

	void RendererContextMtl::submit(Frame* _render, const ClearQuad& _clearQuad, const MipGen& /*_mipGen*/, TextVideoMemBlitter& _textVideoMemBlitter)
	{
		m_cmd.finish(false);

		if (NULL == m_commandBuffer)
		{
			m_commandBuffer = m_cmd.alloc();
		}


		if (_render->m_capture)
		{
			MTL::CaptureManager* captureMgr = getSharedCaptureManager();
			MTL::CaptureDescriptor* captureDesc = newCaptureDescriptor();
			captureDesc->setCaptureObject( (MTL::Device*)m_device);
			captureDesc->setDestination(MTL::CaptureDestinationDeveloperTools);

			NS::Error* err = NULL;
			captureMgr->startCapture(captureDesc, &err);

			if (NULL != err)
			{
				BX_TRACE("Failed to start capture. Error %ld: %s", (long)err->code(), err->localizedDescription()->utf8String() );
			}
		}

		BGFX_MTL_PROFILER_BEGIN_LITERAL("rendererSubmit", kColorFrame);

		int64_t timeBegin = bx::getHPCounter();
		int64_t captureElapsed = 0;

		m_gpuTimer.addHandlers(m_commandBuffer);

		if (m_blitCommandEncoder)
		{
			m_blitCommandEncoder->endEncoding();
			m_blitCommandEncoder = 0;
		}

		updateResolution(_render->m_resolution);

		if (0 != _render->m_numScreenShots
		||  NULL != m_capture)
		{
			if (m_screenshotTarget)
			{
				if (m_screenshotTarget->width()  != m_resolution.width
				||  m_screenshotTarget->height() != m_resolution.height)
				{
					MTL_RELEASE(m_screenshotTarget, 0);
				}
			}

			if (NULL == m_screenshotTarget)
			{
				MTL::TextureDescriptor* desc = newTextureDescriptor();

				desc->setTextureType(MTL::TextureType2D);
				desc->setPixelFormat(getSwapChainPixelFormat(m_mainFrameBuffer.m_swapChain) );
				desc->setWidth(m_resolution.width);
				desc->setHeight(m_resolution.height);
				desc->setDepth(1);
				desc->setMipmapLevelCount(1);
				desc->setSampleCount(1);
				desc->setArrayLength(1);

				if (s_renderMtl->m_hasCPUCacheModesAndStorageModes)
				{
					desc->setCpuCacheMode(MTL::CPUCacheModeDefaultCache);
					desc->setStorageMode(BX_ENABLED(BX_PLATFORM_IOS) || BX_ENABLED(BX_PLATFORM_VISIONOS)
						? MTL::StorageModeShared
						: MTL::StorageModeManaged)
						;

					desc->setUsage(MTL::TextureUsage(0
						| MTL::TextureUsageRenderTarget
						| MTL::TextureUsageShaderRead
						) );
				}

				m_screenshotTarget = m_device->newTexture(desc);
				MTL_RELEASE(desc, 0);
			}
		}
		else
		{
			MTL_RELEASE(m_screenshotTarget, 0);
		}

		m_uniformBuffer = m_uniformBuffers[m_bufferIndex];
		m_bufferIndex = (m_bufferIndex + 1) % BGFX_CONFIG_MAX_FRAME_LATENCY;
		m_uniformBufferVertexOffset = 0;
		m_uniformBufferFragmentOffset = 0;

		if (0 < _render->m_iboffset)
		{
			BGFX_PROFILER_SCOPE("bgfx/Update transient index buffer", kColorResource);
			TransientIndexBuffer* ib = _render->m_transientIb;
			m_indexBuffers[ib->handle.idx].update(0, bx::strideAlign(_render->m_iboffset,4), ib->data, true);
		}

		if (0 < _render->m_vboffset)
		{
			BGFX_PROFILER_SCOPE("bgfx/Update transient vertex buffer", kColorResource);
			TransientVertexBuffer* vb = _render->m_transientVb;
			m_vertexBuffers[vb->handle.idx].update(0, bx::strideAlign(_render->m_vboffset,4), vb->data, true);
		}

		_render->sort();

		RenderDraw currentState;
		currentState.clear();
		currentState.m_stateFlags = BGFX_STATE_NONE;
		currentState.m_stencil    = packStencil(BGFX_STENCIL_NONE, BGFX_STENCIL_NONE);

		RenderBind currentBind;
		currentBind.clear();

		static ViewState viewState;
		viewState.reset(_render);
		uint32_t blendFactor = 0;

		bool wireframe = !!(_render->m_debug&BGFX_DEBUG_WIREFRAME);

		ProgramHandle currentProgram = BGFX_INVALID_HANDLE;
		SortKey key;
		uint16_t view = UINT16_MAX;
		FrameBufferHandle fbh = { BGFX_CONFIG_MAX_FRAME_BUFFERS };

		UniformCacheState ucs(_render);
		BlitState bs(_render);

		const uint64_t primType = 0;
		uint8_t primIndex = uint8_t(primType>>BGFX_STATE_PT_SHIFT);
		PrimInfo prim = s_primInfo[primIndex];
		const uint32_t maxComputeBindings = g_caps.limits.maxComputeBindings;
		const uint32_t maxTextureSamplers = g_caps.limits.maxTextureSamplers;

		MTL::RenderCommandEncoder* rce = NULL;
		PipelineStateMtl* currentPso = NULL;

		bool wasCompute     = false;
		bool viewHasScissor = false;
		Rect viewScissorRect;
		viewScissorRect.clear();

		uint32_t statsNumPrimsSubmitted[BX_COUNTOF(s_primInfo)] = {};
		uint32_t statsNumPrimsRendered[BX_COUNTOF(s_primInfo)]  = {};
		uint32_t statsNumInstances[BX_COUNTOF(s_primInfo)]      = {};
		uint32_t statsNumDrawIndirect[BX_COUNTOF(s_primInfo)]   = {};
		uint32_t statsNumIndices = 0;
		uint32_t statsKeyType[2] = {};

		Profiler<TimerQueryMtl> profiler(
			  _render
			, m_gpuTimer
			, s_viewName
			);

		m_occlusionQuery.resolve(_render);

		if (0 == (_render->m_debug&BGFX_DEBUG_IFH) )
		{
			viewState.m_rect = _render->m_view[0].m_rect;
			int32_t numItems = _render->m_numRenderItems;

			for (int32_t item = 0; item < numItems;)
			{
				const uint64_t encodedKey = _render->m_sortKeys[item];
				const bool isCompute = key.decode(encodedKey, _render->m_viewRemap);
				statsKeyType[isCompute]++;

				const bool viewChanged = 0
					|| key.m_view != view
					|| item == numItems
					;

				const uint32_t itemIdx       = _render->m_sortValues[item];
				const RenderItem& renderItem = _render->m_renderItem[itemIdx];
				const RenderBind& renderBind = _render->m_renderItemBind[itemIdx];
				++item;

				if (viewChanged
				|| (!isCompute && wasCompute) )
				{
					view = key.m_view;
					currentProgram = BGFX_INVALID_HANDLE;

					if (item > 1)
					{
						profiler.end();
					}

					BGFX_MTL_PROFILER_END();
					setViewType(view, "  ");
					BGFX_MTL_PROFILER_BEGIN(view, kColorView);

					profiler.begin(view);

					viewState.m_rect = _render->m_view[view].m_rect;

					submitUniformCache(ucs, view);
					submitBlit(bs, view);

					if (!isCompute)
					{
						const Rect& scissorRect = _render->m_view[view].m_scissor;
						viewHasScissor = !scissorRect.isZero();
						viewScissorRect = viewHasScissor ? scissorRect : viewState.m_rect;
						Clear& clr = _render->m_view[view].m_clear;

						const Rect viewRect = viewState.m_rect;
						bool clearWithRenderPass = false;

						if (NULL == m_renderCommandEncoder
						||  fbh.idx != _render->m_view[view].m_fbh.idx)
						{
							endEncoding();

							MTL::RenderPassDescriptor* renderPassDescriptor = newRenderPassDescriptor();
							renderPassDescriptor->setVisibilityResultBuffer(m_occlusionQuery.m_buffer);

							fbh = _render->m_view[view].m_fbh;

							uint32_t width  = m_resolution.width;
							uint32_t height = m_resolution.height;

							if (isValid(fbh) )
							{
								FrameBufferMtl& frameBuffer = m_frameBuffers[fbh.idx];
								width  = frameBuffer.m_width;
								height = frameBuffer.m_height;
							}

							clearWithRenderPass = true
								&& 0      == viewRect.m_x
								&& 0      == viewRect.m_y
								&& width  == viewRect.m_width
								&& height == viewRect.m_height
								;

							setFrameBuffer(renderPassDescriptor, fbh);

							if (clearWithRenderPass)
							{
								for (uint32_t ii = 0; ii < g_caps.limits.maxFBAttachments; ++ii)
								{
									MTL::RenderPassColorAttachmentDescriptor* desc = renderPassDescriptor->colorAttachments()->object(ii);

									if (desc->texture() != NULL)
									{
										if (0 != (BGFX_CLEAR_COLOR & clr.m_flags) )
										{
											if (0 != (BGFX_CLEAR_COLOR_USE_PALETTE & clr.m_flags) )
											{
												uint8_t index = (uint8_t)bx::min(BGFX_CONFIG_MAX_COLOR_PALETTE-1, clr.m_index[ii]);
												const float* rgba = _render->m_colorPalette[index];
												const float rr = rgba[0];
												const float gg = rgba[1];
												const float bb = rgba[2];
												const float aa = rgba[3];
												desc->setClearColor(MTL::ClearColor::Make(rr, gg, bb, aa) );
											}
											else
											{
												float rr = clr.m_index[0]*1.0f/255.0f;
												float gg = clr.m_index[1]*1.0f/255.0f;
												float bb = clr.m_index[2]*1.0f/255.0f;
												float aa = clr.m_index[3]*1.0f/255.0f;
												desc->setClearColor(MTL::ClearColor::Make(rr, gg, bb, aa) );
											}

											desc->setLoadAction(MTL::LoadActionClear);
										}
										else
										{
											desc->setLoadAction(MTL::LoadActionLoad);
										}

										const MTL::StoreAction multisampleStoreAction = m_hasStoreActionStoreAndMultisampleResolve
											? MTL::StoreActionStoreAndMultisampleResolve
											: MTL::StoreActionMultisampleResolve
											;

										desc->setStoreAction(desc->texture()->sampleCount() > 1
											? multisampleStoreAction
											: MTL::StoreActionStore
											);
									}
								}

								MTL::RenderPassDepthAttachmentDescriptor* depthAttachment = renderPassDescriptor->depthAttachment();

								if (NULL != depthAttachment->texture() )
								{
									depthAttachment->setClearDepth(clr.m_depth);
									depthAttachment->setLoadAction(0 != (BGFX_CLEAR_DEPTH & clr.m_flags)
										? MTL::LoadActionClear
										: MTL::LoadActionLoad)
										;
									depthAttachment->setStoreAction(MTL::StoreActionStore);
								}

								MTL::RenderPassStencilAttachmentDescriptor* stencilAttachment = renderPassDescriptor->stencilAttachment();

								if (NULL != stencilAttachment->texture() )
								{
									stencilAttachment->setClearStencil(clr.m_stencil);
									stencilAttachment->setLoadAction(0 != (BGFX_CLEAR_STENCIL & clr.m_flags)
										? MTL::LoadActionClear
										: MTL::LoadActionLoad)
										;
									stencilAttachment->setStoreAction(MTL::StoreActionStore);
								}
							}
							else
							{
								for (uint32_t ii = 0; ii < g_caps.limits.maxFBAttachments; ++ii)
								{
									MTL::RenderPassColorAttachmentDescriptor* desc = renderPassDescriptor->colorAttachments()->object(ii);
									if (desc->texture() != NULL)
									{
										desc->setLoadAction(MTL::LoadActionLoad);

										const MTL::StoreAction multisampleStoreAction = m_hasStoreActionStoreAndMultisampleResolve
											? MTL::StoreActionStoreAndMultisampleResolve
											: MTL::StoreActionMultisampleResolve
											;

										desc->setStoreAction(desc->texture()->sampleCount() > 1
											? multisampleStoreAction
											: MTL::StoreActionStore
											);
									}
								}

								MTL::RenderPassDepthAttachmentDescriptor* depthAttachment = renderPassDescriptor->depthAttachment();

								if (NULL != depthAttachment->texture() )
								{
									depthAttachment->setLoadAction(MTL::LoadActionLoad);
									depthAttachment->setStoreAction(MTL::StoreActionStore);
								}

								MTL::RenderPassStencilAttachmentDescriptor* stencilAttachment = renderPassDescriptor->stencilAttachment();

								if (NULL != stencilAttachment->texture() )
								{
									stencilAttachment->setLoadAction(MTL::LoadActionLoad);
									stencilAttachment->setStoreAction(MTL::StoreActionStore);
								}
							}

							if (m_variableRateShadingSupported)
							{
								MTL::RasterizationRateLayerDescriptor* rrld = newRasterizationRateLayerDescriptor(s_shadingRate[_render->m_view[view].m_shadingRate]);
								MTL::RasterizationRateMapDescriptor*   rrmd = newRasterizationRateMapDescriptor();
								rrmd->setScreenSize(MTL::Size::Make(viewRect.m_width, viewRect.m_height, 0) );
								rrmd->setLayer(rrld, 0);

								renderPassDescriptor->setRasterizationRateMap(m_device->newRasterizationRateMap(rrmd) );
							}

							rce = m_commandBuffer->renderCommandEncoder(renderPassDescriptor);
							m_renderCommandEncoder = rce;
							m_renderCommandEncoderFrameBufferHandle = fbh;

							MTL_RELEASE(renderPassDescriptor, 0);

							if (m_depthClamp)
							{
								rce->setDepthClipMode(MTL::DepthClipModeClamp);
							}
						}
						else if (BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
						{
							rce->popDebugGroup();
						}

						if (BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
						{
							rce->pushDebugGroup(nsstr(s_viewName[view]) );
						}

						rce->setTriangleFillMode( (MTL::TriangleFillMode)wireframe ? MTL::TriangleFillModeLines : MTL::TriangleFillModeFill);

						{
							MTL::Viewport vp;
							vp.originX = viewState.m_rect.m_x;
							vp.originY = viewState.m_rect.m_y;
							vp.width   = viewState.m_rect.m_width;
							vp.height  = viewState.m_rect.m_height;
							vp.znear   = 0.0f;
							vp.zfar    = 1.0f;
							rce->setViewport(vp);

							MTL::ScissorRect sciRect = {
								viewState.m_rect.m_x,
								viewState.m_rect.m_y,
								viewState.m_rect.m_width,
								viewState.m_rect.m_height
							};
							rce->setScissorRect(sciRect);
						}

						if (BGFX_CLEAR_NONE != (clr.m_flags & BGFX_CLEAR_MASK)
							&& !clearWithRenderPass)
						{
							clearQuad(_clearQuad, viewState.m_rect, clr, _render->m_colorPalette);
						}
					}
				}

				if (isCompute)
				{
					if (!wasCompute)
					{
						wasCompute = true;

						endEncoding();
						rce = NULL;

						setViewType(view, "C");
						BGFX_MTL_PROFILER_END();
						BGFX_MTL_PROFILER_BEGIN(view, kColorCompute);

						m_computeCommandEncoder = m_commandBuffer->computeCommandEncoder();
					}
					else if (viewChanged && BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
					{
						m_computeCommandEncoder->popDebugGroup();
					}

					if (viewChanged
					&&  BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
					{
						s_viewName[view][3] = L'C';
						m_computeCommandEncoder->pushDebugGroup(nsstr(s_viewName[view]) );
						s_viewName[view][3] = L' ';
					}

					const RenderCompute& compute = renderItem.compute;

					rendererUpdateUniforms(this, _render->m_uniformBuffer[compute.m_uniformIdx], compute.m_uniformBegin, compute.m_uniformEnd);

					if (key.m_program.idx != currentProgram.idx)
					{
						currentProgram = key.m_program;

						currentPso = getComputePipelineState(currentProgram);

						if (NULL == currentPso)
						{
							currentProgram = BGFX_INVALID_HANDLE;
							continue;
						}

						m_computeCommandEncoder->setComputePipelineState(currentPso->m_cps);
					}

					if (isValid(currentProgram)
					&&  NULL != currentPso)
					{
						uint32_t vertexUniformBufferSize = currentPso->m_vshConstantBufferSize;

						if (0 != vertexUniformBufferSize)
						{
							m_uniformBufferVertexOffset = bx::alignUp(
								  m_uniformBufferVertexOffset
								, currentPso->m_vshConstantBufferAlignment
								);
							m_computeCommandEncoder->setBuffer(m_uniformBuffer, m_uniformBufferVertexOffset, 0);
						}

						UniformBuffer* vcb = currentPso->m_vshConstantBuffer;
						if (NULL != vcb)
						{
							commit(*vcb);
						}

						viewState.setPredefined<4>(this, view, *currentPso, _render, compute);

						m_uniformBufferVertexOffset += vertexUniformBufferSize;
					}

					for (uint8_t stage = 0; stage < maxComputeBindings; ++stage)
					{
						const Binding& bind = renderBind.m_bind[stage];
						if (kInvalidHandle != bind.m_idx)
						{
							switch (bind.m_type)
							{
								case Binding::Image:
								{
									TextureMtl& texture = m_textures[bind.m_idx];
									m_computeCommandEncoder->setTexture(texture.getTextureMipLevel(bind.m_mip), stage);
								}
								break;

								case Binding::Texture:
								{
									TextureMtl& texture = m_textures[bind.m_idx];
									uint32_t flags = bind.m_samplerFlags;

									m_computeCommandEncoder->setTexture(texture.m_ptr, stage);
									m_computeCommandEncoder->setSamplerState(
										0 == (BGFX_SAMPLER_INTERNAL_DEFAULT & flags)
										? getSamplerState(flags)
										: texture.m_sampler
										, stage
										);
								}
								break;

								case Binding::IndexBuffer:
								case Binding::VertexBuffer:
								{
									const BufferMtl& buffer = Binding::IndexBuffer == bind.m_type
									? m_indexBuffers[bind.m_idx]
									: m_vertexBuffers[bind.m_idx]
									;
									m_computeCommandEncoder->setBuffer(buffer.m_ptr, 0, stage + 1);
								}
								break;
							}
						}
					}

					MTL::Size threadsPerGroup = MTL::Size::Make(
						  currentPso->m_numThreads[0]
						, currentPso->m_numThreads[1]
						, currentPso->m_numThreads[2]
						);

					if (isValid(compute.m_indirectBuffer) )
					{
						const VertexBufferMtl& vb = m_vertexBuffers[compute.m_indirectBuffer.idx];

						uint32_t numDrawIndirect = UINT32_MAX == compute.m_numIndirect
						? vb.m_size/BGFX_CONFIG_DRAW_INDIRECT_STRIDE
						: compute.m_numIndirect
						;

						uint32_t args = compute.m_startIndirect * BGFX_CONFIG_DRAW_INDIRECT_STRIDE;
						for (uint32_t ii = 0; ii < numDrawIndirect; ++ii)
						{
							m_computeCommandEncoder->dispatchThreadgroups(
								  vb.m_ptr
								, args
								, threadsPerGroup
								);
							args += BGFX_CONFIG_DRAW_INDIRECT_STRIDE;
						}
					}
					else
					{
						m_computeCommandEncoder->dispatchThreadgroups(
							  MTL::Size::Make(compute.m_numX, compute.m_numY, compute.m_numZ)
							, threadsPerGroup
							);
					}
					continue;
				}


				bool resetState = viewChanged || wasCompute;

				if (wasCompute)
				{
					wasCompute = false;
					currentProgram = BGFX_INVALID_HANDLE;

					setViewType(view, " ");
					BGFX_MTL_PROFILER_END();
					BGFX_MTL_PROFILER_BEGIN(view, kColorDraw);
				}

				const RenderDraw& draw = renderItem.draw;

				const bool hasOcclusionQuery = 0 != (draw.m_stateFlags & BGFX_STATE_INTERNAL_OCCLUSION_QUERY);
				{
					const bool occluded = true
						&& isValid(draw.m_occlusionQuery)
						&& !hasOcclusionQuery
						&& !isVisible(_render, draw.m_occlusionQuery, 0 != (draw.m_submitFlags&BGFX_SUBMIT_INTERNAL_OCCLUSION_VISIBLE) )
						;

					if (occluded
					||  _render->m_frameCache.isZeroArea(viewScissorRect, draw.m_scissor) )
					{
						if (resetState)
						{
							currentState.clear();
							currentState.m_scissor = !draw.m_scissor;
							currentBind.clear();
						}

						continue;
					}
				}

				const uint64_t newFlags = draw.m_stateFlags;
				uint64_t changedFlags = currentState.m_stateFlags ^ draw.m_stateFlags;
				currentState.m_stateFlags = newFlags;

				const uint64_t newStencil = draw.m_stencil;
				uint64_t changedStencil = currentState.m_stencil ^ draw.m_stencil;
				currentState.m_stencil = newStencil;

				if (resetState)
				{
					currentState.clear();
					currentState.m_scissor = !draw.m_scissor;
					changedFlags = BGFX_STATE_MASK;
					changedStencil = packStencil(BGFX_STENCIL_MASK, BGFX_STENCIL_MASK);
					currentState.m_stateFlags = newFlags;
					currentState.m_stencil    = newStencil;

					currentBind.clear();

					currentProgram = BGFX_INVALID_HANDLE;
					setDepthStencilState(newFlags, packStencil(BGFX_STENCIL_DEFAULT, BGFX_STENCIL_DEFAULT) );

					const uint64_t pt = newFlags&BGFX_STATE_PT_MASK;
					primIndex = uint8_t(pt>>BGFX_STATE_PT_SHIFT);
				}

				if (prim.m_type != s_primInfo[primIndex].m_type)
				{
					prim = s_primInfo[primIndex];
				}

				uint16_t scissor = draw.m_scissor;
				if (currentState.m_scissor != scissor)
				{
					currentState.m_scissor = scissor;

					MTL::ScissorRect rc;
					if (UINT16_MAX == scissor)
					{
						if (viewHasScissor)
						{
							rc.x   = viewScissorRect.m_x;
							rc.y    = viewScissorRect.m_y;
							rc.width  = viewScissorRect.m_width;
							rc.height = viewScissorRect.m_height;
						}
						else
						{   // can't disable: set to view rect
							rc.x   = viewState.m_rect.m_x;
							rc.y    = viewState.m_rect.m_y;
							rc.width  = viewState.m_rect.m_width;
							rc.height = viewState.m_rect.m_height;
						}
					}
					else
					{
						Rect scissorRect;
						scissorRect.setIntersect(viewScissorRect, _render->m_frameCache.m_rectCache.m_cache[scissor]);

						rc.x      = scissorRect.m_x;
						rc.y      = scissorRect.m_y;
						rc.width  = scissorRect.m_width;
						rc.height = scissorRect.m_height;
					}

					rce->setScissorRect(rc);
				}

				if ( (0
					 | BGFX_STATE_WRITE_Z
					 | BGFX_STATE_DEPTH_TEST_MASK
					 ) & changedFlags
				|| 0 != changedStencil)
				{
					setDepthStencilState(newFlags,newStencil);
				}

				if ( (0
					 | BGFX_STATE_CULL_MASK
					 | BGFX_STATE_FRONT_CCW
					 | BGFX_STATE_ALPHA_REF_MASK
					 | BGFX_STATE_PT_MASK
					 ) & changedFlags)
				{
					if (BGFX_STATE_FRONT_CCW & changedFlags)
					{
						rce->setFrontFacingWinding( (newFlags&BGFX_STATE_FRONT_CCW)
							? MTL::WindingCounterClockwise
							: MTL::WindingClockwise
							);
					}

					if (BGFX_STATE_CULL_MASK & changedFlags)
					{
						const uint64_t pt = newFlags&BGFX_STATE_CULL_MASK;
						const uint8_t cullIndex = uint8_t(pt>>BGFX_STATE_CULL_SHIFT);
						rce->setCullMode( (MTL::CullMode)s_cullMode[cullIndex]);
					}

					if (BGFX_STATE_ALPHA_REF_MASK & changedFlags)
					{
						uint32_t ref = (newFlags&BGFX_STATE_ALPHA_REF_MASK)>>BGFX_STATE_ALPHA_REF_SHIFT;
						viewState.m_alphaRef = ref/255.0f;
					}

					const uint64_t pt = newFlags&BGFX_STATE_PT_MASK;
					primIndex = uint8_t(pt>>BGFX_STATE_PT_SHIFT);
					if (prim.m_type != s_primInfo[primIndex].m_type)
					{
						prim = s_primInfo[primIndex];
					}
				}

				if (blendFactor != draw.m_rgba
				&& !(newFlags & BGFX_STATE_BLEND_INDEPENDENT) )
				{
					const uint32_t rgba = draw.m_rgba;
					float rr = ( (rgba>>24)     )/255.0f;
					float gg = ( (rgba>>16)&0xff)/255.0f;
					float bb = ( (rgba>> 8)&0xff)/255.0f;
					float aa = ( (rgba    )&0xff)/255.0f;
					rce->setBlendColor(rr,gg,bb,aa);

					blendFactor = draw.m_rgba;
				}

				bool programChanged = false;
				rendererUpdateUniforms(this, _render->m_uniformBuffer[draw.m_uniformIdx], draw.m_uniformBegin, draw.m_uniformEnd);

				bool vertexStreamChanged = hasVertexStreamChanged(currentState, draw);

				if (key.m_program.idx != currentProgram.idx
				||  vertexStreamChanged
				|| (0
				   | BGFX_STATE_BLEND_MASK
				   | BGFX_STATE_BLEND_EQUATION_MASK
				   | BGFX_STATE_WRITE_RGB
				   | BGFX_STATE_WRITE_A
				   | BGFX_STATE_BLEND_INDEPENDENT
				   | BGFX_STATE_MSAA
				   | BGFX_STATE_BLEND_ALPHA_TO_COVERAGE
				   ) & changedFlags
				|| ( (blendFactor != draw.m_rgba) && !!(newFlags & BGFX_STATE_BLEND_INDEPENDENT) ) )
				{
					currentProgram = key.m_program;

					currentState.m_streamMask             = draw.m_streamMask;
					currentState.m_instanceDataBuffer.idx = draw.m_instanceDataBuffer.idx;
					currentState.m_instanceDataOffset     = draw.m_instanceDataOffset;
					currentState.m_instanceDataStride     = draw.m_instanceDataStride;

					const VertexLayout* layouts[BGFX_CONFIG_MAX_VERTEX_STREAMS];

					uint32_t numVertices = draw.m_numVertices;
					uint8_t  numStreams  = 0;

					for (BitMaskToIndexIteratorT it(draw.m_streamMask)
						; !it.isDone()
						; it.next(), numStreams++
						)
					{
						const uint8_t idx = it.idx;

						currentState.m_stream[idx].m_layoutHandle   = draw.m_stream[idx].m_layoutHandle;
						currentState.m_stream[idx].m_handle         = draw.m_stream[idx].m_handle;
						currentState.m_stream[idx].m_startVertex    = draw.m_stream[idx].m_startVertex;

						const uint16_t handle = draw.m_stream[idx].m_handle.idx;
						const VertexBufferMtl& vb = m_vertexBuffers[handle];
						const uint16_t decl = isValid(draw.m_stream[idx].m_layoutHandle)
							? draw.m_stream[idx].m_layoutHandle.idx
							: vb.m_layoutHandle.idx;
						const VertexLayout& layout = m_vertexLayouts[decl];
						const uint32_t stride = layout.m_stride;

						layouts[numStreams] = &layout;

						numVertices = bx::min(UINT32_MAX == draw.m_numVertices
							? vb.m_size/stride
							: draw.m_numVertices
							, numVertices
							);
						const uint32_t offset = draw.m_stream[idx].m_startVertex * stride;

						rce->setVertexBuffer(vb.m_ptr, offset, idx+1);
					}

					if (!isValid(currentProgram) )
					{
						continue;
					}

					currentPso = NULL;

					if (0 < numStreams)
					{
						currentPso = getPipelineState(
								newFlags
							, draw.m_rgba
							, fbh
							, numStreams
							, layouts
							, currentProgram
							, draw.m_instanceDataStride/16
							);
					}

					if (NULL == currentPso)
					{
						currentProgram = BGFX_INVALID_HANDLE;
						continue;
					}

					rce->setRenderPipelineState(currentPso->m_rps);

					if (isValid(draw.m_instanceDataBuffer) )
					{
						const VertexBufferMtl& inst = m_vertexBuffers[draw.m_instanceDataBuffer.idx];
						rce->setVertexBuffer(inst.m_ptr, draw.m_instanceDataOffset, numStreams+1);
					}

					programChanged = true;
				}

				if (isValid(currentProgram) )
				{
					const uint32_t vertexUniformBufferSize   = currentPso->m_vshConstantBufferSize;
					const uint32_t fragmentUniformBufferSize = currentPso->m_fshConstantBufferSize;

					if (0 != vertexUniformBufferSize)
					{
						m_uniformBufferVertexOffset = bx::alignUp(
							  m_uniformBufferVertexOffset
							, currentPso->m_vshConstantBufferAlignment
							);
						rce->setVertexBuffer(m_uniformBuffer, m_uniformBufferVertexOffset, 0);
					}

					m_uniformBufferFragmentOffset = m_uniformBufferVertexOffset + vertexUniformBufferSize;
					if (0 != fragmentUniformBufferSize)
					{
						m_uniformBufferFragmentOffset = bx::alignUp(
							  m_uniformBufferFragmentOffset
							, currentPso->m_fshConstantBufferAlignment
							);
						rce->setFragmentBuffer(m_uniformBuffer, m_uniformBufferFragmentOffset, 0);
					}

					UniformBuffer* vcb = currentPso->m_vshConstantBuffer;
					if (NULL != vcb)
					{
						commit(*vcb);
					}

					UniformBuffer* fcb = currentPso->m_fshConstantBuffer;
					if (NULL != fcb)
					{
						commit(*fcb);
					}

					viewState.setPredefined<4>(this, view, *currentPso, _render, draw);

					m_uniformBufferFragmentOffset += fragmentUniformBufferSize;
					m_uniformBufferVertexOffset    = m_uniformBufferFragmentOffset;
				}

				if (isValid(currentProgram) )
				{
					uint8_t* bindingTypes = currentPso->m_bindingTypes;
					for (uint8_t stage = 0; stage < maxTextureSamplers; ++stage)
					{
						const Binding& bind = renderBind.m_bind[stage];
						Binding& current = currentBind.m_bind[stage];
						if (current.m_idx          != bind.m_idx
						||  current.m_type         != bind.m_type
						||  current.m_samplerFlags != bind.m_samplerFlags
						||  programChanged)
						{
							if (kInvalidHandle != bind.m_idx)
							{
								switch (bind.m_type)
								{
								case Binding::Image:
									{
										if (bind.m_access == Access::ReadWrite && 0 == (g_caps.supported & BGFX_CAPS_IMAGE_RW) )
										{
											BGFX_FATAL(
												false
												, Fatal::DebugCheck
												, "Failed to set image with access: Access::ReadWrite, device is not support image read&write"
												);
										}

										if ( (bind.m_access == Access::Read      && (0 == (g_caps.formats[bind.m_format] &  BGFX_CAPS_FORMAT_TEXTURE_IMAGE_READ) ) )
										||   (bind.m_access == Access::Write     && (0 == (g_caps.formats[bind.m_format] &  BGFX_CAPS_FORMAT_TEXTURE_IMAGE_WRITE) ) )
										||   (bind.m_access == Access::ReadWrite && (0 == (g_caps.formats[bind.m_format] & (BGFX_CAPS_FORMAT_TEXTURE_IMAGE_READ|BGFX_CAPS_FORMAT_TEXTURE_IMAGE_WRITE) ) ) )
										)
										{
											BGFX_FATAL(
												false
												, Fatal::DebugCheck
												, "Failed to set image with access: %s, format:%s is not supported"
												, s_accessNames[bind.m_access]
												, bimg::getName(bimg::TextureFormat::Enum(bind.m_format) )
												);
										}

										TextureMtl& texture = m_textures[bind.m_idx];
										texture.commit(
											stage
											, 0 != (bindingTypes[stage] & PipelineStateMtl::BindToVertexShader)
											, 0 != (bindingTypes[stage] & PipelineStateMtl::BindToFragmentShader)
											, bind.m_samplerFlags
											, bind.m_mip
											);
									}
									break;

								case Binding::Texture:
									{
										TextureMtl& texture = m_textures[bind.m_idx];
										texture.commit(
											stage
											, 0 != (bindingTypes[stage] & PipelineStateMtl::BindToVertexShader)
											, 0 != (bindingTypes[stage] & PipelineStateMtl::BindToFragmentShader)
											, bind.m_samplerFlags
											);
									}
									break;

								case Binding::IndexBuffer:
								case Binding::VertexBuffer:
									{
										const BufferMtl& buffer = Binding::IndexBuffer == bind.m_type
											? m_indexBuffers[bind.m_idx]
											: m_vertexBuffers[bind.m_idx]
											;

										if (0 != (bindingTypes[stage] & PipelineStateMtl::BindToVertexShader) )
										{
											rce->setVertexBuffer(buffer.m_ptr, 0, stage + 1);
										}

										if (0 != (bindingTypes[stage] & PipelineStateMtl::BindToFragmentShader) )
										{
											rce->setFragmentBuffer(buffer.m_ptr, 0, stage + 1);
										}
									}
									break;
								}
							}
						}

						current = bind;
					}
				}

				if (0 != currentState.m_streamMask)
				{
					uint32_t numVertices = draw.m_numVertices;

					if (UINT32_MAX == numVertices)
					{
						const VertexBufferMtl& vb = m_vertexBuffers[currentState.m_stream[0].m_handle.idx];
						uint16_t decl = !isValid(vb.m_layoutHandle) ? draw.m_stream[0].m_layoutHandle.idx : vb.m_layoutHandle.idx;
						const VertexLayout& layout = m_vertexLayouts[decl];
						numVertices = vb.m_size/layout.m_stride;
					}

					uint32_t numIndices        = 0;
					uint32_t numPrimsSubmitted = 0;
					uint32_t numInstances      = 0;
					uint32_t numPrimsRendered  = 0;
					uint32_t numDrawIndirect   = 0;

					if (hasOcclusionQuery)
					{
						m_occlusionQuery.begin(rce, _render, draw.m_occlusionQuery);
					}

					if (isValid(draw.m_indirectBuffer) )
					{
						const VertexBufferMtl& vb = m_vertexBuffers[draw.m_indirectBuffer.idx];

						if (isValid(draw.m_indexBuffer) )
						{
							const bool isIndex16           = draw.isIndex16();
							const MTL::IndexType indexFormat = isIndex16 ? (MTL::IndexType)MTL::IndexTypeUInt16 : (MTL::IndexType)MTL::IndexTypeUInt32;
							const IndexBufferMtl& ib       = m_indexBuffers[draw.m_indexBuffer.idx];

							numDrawIndirect = UINT32_MAX == draw.m_numIndirect
								? vb.m_size/BGFX_CONFIG_DRAW_INDIRECT_STRIDE
								: draw.m_numIndirect
								;

							for (uint32_t ii = 0; ii < numDrawIndirect; ++ii)
							{
								rce->drawIndexedPrimitives(prim.m_type, indexFormat, ib.m_ptr, 0, vb.m_ptr, (draw.m_startIndirect + ii )* BGFX_CONFIG_DRAW_INDIRECT_STRIDE);
							}
						}
						else
						{
							numDrawIndirect = UINT32_MAX == draw.m_numIndirect
								? vb.m_size/BGFX_CONFIG_DRAW_INDIRECT_STRIDE
								: draw.m_numIndirect
								;

							for (uint32_t ii = 0; ii < numDrawIndirect; ++ii)
							{
								rce->drawPrimitives(prim.m_type, vb.m_ptr, (draw.m_startIndirect + ii) * BGFX_CONFIG_DRAW_INDIRECT_STRIDE);
							}
						}
					}
					else
					{
						if (isValid(draw.m_indexBuffer) )
						{
							const bool isIndex16           = draw.isIndex16();
							const uint32_t indexSize       = isIndex16 ? 2 : 4;
							const MTL::IndexType indexFormat = isIndex16 ? (MTL::IndexType)MTL::IndexTypeUInt16 : (MTL::IndexType)MTL::IndexTypeUInt32;
							const IndexBufferMtl& ib       = m_indexBuffers[draw.m_indexBuffer.idx];

							if (UINT32_MAX == draw.m_numIndices)
							{
								numIndices        = ib.m_size/indexSize;
								numPrimsSubmitted = numIndices/prim.m_div - prim.m_sub;
								numInstances      = draw.m_numInstances;
								numPrimsRendered  = numPrimsSubmitted*draw.m_numInstances;

								rce->drawIndexedPrimitives(prim.m_type, numIndices, indexFormat, ib.m_ptr, 0, draw.m_numInstances);
							}
							else if (prim.m_min <= draw.m_numIndices)
							{
								numIndices        = draw.m_numIndices;
								numPrimsSubmitted = numIndices/prim.m_div - prim.m_sub;
								numInstances      = draw.m_numInstances;
								numPrimsRendered  = numPrimsSubmitted*draw.m_numInstances;

								rce->drawIndexedPrimitives(prim.m_type, numIndices, indexFormat, ib.m_ptr, draw.m_startIndex * indexSize,numInstances);
							}
						}
						else
						{
							numPrimsSubmitted = numVertices/prim.m_div - prim.m_sub;
							numInstances      = draw.m_numInstances;
							numPrimsRendered  = numPrimsSubmitted*draw.m_numInstances;

							rce->drawPrimitives(prim.m_type, 0, numVertices, draw.m_numInstances);
						}
					}

					if (hasOcclusionQuery)
					{
						m_occlusionQuery.end(rce);
					}

					statsNumPrimsSubmitted[primIndex] += numPrimsSubmitted;
					statsNumPrimsRendered[primIndex]  += numPrimsRendered;
					statsNumInstances[primIndex]      += numInstances;
					statsNumDrawIndirect[primIndex]   += numDrawIndirect;
					statsNumIndices                   += numIndices;
				}
			}

			if (wasCompute)
			{
				invalidateCompute();

				setViewType(view, "C");
				BGFX_MTL_PROFILER_END();
				BGFX_MTL_PROFILER_BEGIN(view, kColorCompute);
			}

			submitBlit(bs, BGFX_CONFIG_MAX_VIEWS);

			if (0 < _render->m_numRenderItems)
			{
				captureElapsed = -bx::getHPCounter();
				capture();
				rce = m_renderCommandEncoder;
				captureElapsed += bx::getHPCounter();

				profiler.end();
			}
		}

		if (BX_ENABLED(BGFX_CONFIG_DEBUG_ANNOTATION) )
		{
			if (0 < _render->m_numRenderItems)
			{
				rce->popDebugGroup();
			}
		}

		BGFX_MTL_PROFILER_END();

		int64_t timeEnd = bx::getHPCounter();
		int64_t frameTime = timeEnd - timeBegin;

		static int64_t min = frameTime;
		static int64_t max = frameTime;
		min = bx::min<int64_t>(min, frameTime);
		max = bx::max<int64_t>(max, frameTime);

		static uint32_t maxGpuLatency = 0;
		static double   maxGpuElapsed = 0.0f;
		double elapsedGpuMs = 0.0;

		do
		{
			double toGpuMs = 1000.0 / double(m_gpuTimer.m_frequency);
			elapsedGpuMs   = m_gpuTimer.m_elapsed * toGpuMs;
			maxGpuElapsed  = elapsedGpuMs > maxGpuElapsed ? elapsedGpuMs : maxGpuElapsed;
		}
		while (m_gpuTimer.get() );

		maxGpuLatency = bx::max<int32_t>(maxGpuLatency, m_gpuTimer.m_control.getNumUsed()-1);

		const int64_t timerFreq = bx::getHPFrequency();

		Stats& perfStats = _render->m_perfStats;
		perfStats.cpuTimeBegin  = timeBegin;
		perfStats.cpuTimeEnd    = timeEnd;
		perfStats.cpuTimerFreq  = timerFreq;
		perfStats.gpuTimeBegin  = m_gpuTimer.m_begin;
		perfStats.gpuTimeEnd    = m_gpuTimer.m_end;
		perfStats.gpuTimerFreq  = m_gpuTimer.m_frequency;
		perfStats.numDraw       = statsKeyType[0];
		perfStats.numCompute    = statsKeyType[1];
		perfStats.numBlit       = _render->m_numBlitItems;
		perfStats.maxGpuLatency = maxGpuLatency;
		perfStats.gpuFrameNum   = 0; // TODO: take from TimerQueryMtl::Result
		bx::memCopy(perfStats.numPrims, statsNumPrimsRendered, sizeof(perfStats.numPrims) );
		perfStats.gpuMemoryMax  = -INT64_MAX;
		perfStats.gpuMemoryUsed = -INT64_MAX;

		rce->setTriangleFillMode(MTL::TriangleFillModeFill);

		if (_render->m_debug & (BGFX_DEBUG_IFH|BGFX_DEBUG_STATS) )
		{
			rce->pushDebugGroup(nsstr("debugstats") );

			TextVideoMem& tvm = m_textVideoMem;

			static int64_t next = timeEnd;

			if (timeEnd >= next)
			{
				next = timeEnd + timerFreq;

				double freq = double(timerFreq);
				double toMs = 1000.0/freq;

				tvm.clear();
				uint16_t pos = 0;
				tvm.printf(0, pos++, BGFX_CONFIG_DEBUG ? 0x8c : 0x8f
					, " %s / " BX_COMPILER_NAME
					  " / " BX_CPU_NAME
					  " / " BX_ARCH_NAME
					  " / " BX_PLATFORM_NAME
					  " / Version 1.%d.%d (commit: " BGFX_REV_SHA1 ")"
					, getRendererName()
					, BGFX_API_VERSION
					, BGFX_REV_NUMBER
					);

				pos = 10;
				tvm.printf(10, pos++, 0x8b, "        Frame: %7.3f, % 7.3f \x1f, % 7.3f \x1e [ms] / % 6.2f FPS "
					, double(frameTime)*toMs
					, double(min)*toMs
					, double(max)*toMs
					, freq/frameTime
					);

				const uint32_t msaa = (m_resolution.reset&BGFX_RESET_MSAA_MASK)>>BGFX_RESET_MSAA_SHIFT;
				tvm.printf(10, pos++, 0x8b, "  Reset flags: [%c] vsync, [%c] MSAAx%d, [%c] MaxAnisotropy "
					, !!(m_resolution.reset&BGFX_RESET_VSYNC) ? '\xfe' : ' '
					, 0 != msaa ? '\xfe' : ' '
					, 1<<msaa
					, !!(m_resolution.reset&BGFX_RESET_MAXANISOTROPY) ? '\xfe' : ' '
					);

				double elapsedCpuMs = double(frameTime)*toMs;
				tvm.printf(10, pos++, 0x8b, "    Submitted: %4d (draw %4d, compute %4d) / CPU %3.4f [ms] %c GPU %3.4f [ms] (latency %d)"
					, _render->m_numRenderItems
					, statsKeyType[0]
					, statsKeyType[1]
					, elapsedCpuMs
					, elapsedCpuMs > maxGpuElapsed ? '>' : '<'
					, maxGpuElapsed
					, maxGpuLatency
					);
				maxGpuLatency = 0;
				maxGpuElapsed = 0.0;

				for (uint32_t ii = 0; ii < Topology::Count; ++ii)
				{
					tvm.printf(10, pos++, 0x8b, "   %10s: %7d (#inst: %5d), submitted: %7d"
						, getName(Topology::Enum(ii) )
						, statsNumPrimsRendered[ii]
						, statsNumInstances[ii]
						, statsNumPrimsSubmitted[ii]
						);
				}

				tvm.printf(10, pos++, 0x8b, "      Indices: %7d ", statsNumIndices);
				tvm.printf(10, pos++, 0x8b, "     DVB size: %7d ", _render->m_vboffset);
				tvm.printf(10, pos++, 0x8b, "     DIB size: %7d ", _render->m_iboffset);

				pos++;
				double captureMs = double(captureElapsed)*toMs;
				tvm.printf(10, pos++, 0x8b, "     Capture: %3.4f [ms]", captureMs);

				uint8_t attr[2] = { 0x8c, 0x8a };
				uint8_t attrIndex = _render->m_waitSubmit < _render->m_waitRender;

				tvm.printf(10, pos++, attr[attrIndex    &1], " Submit wait: %3.4f [ms]", _render->m_waitSubmit*toMs);
				tvm.printf(10, pos++, attr[(attrIndex+1)&1], " Render wait: %3.4f [ms]", _render->m_waitRender*toMs);

				min = frameTime;
				max = frameTime;
			}

			dbgTextSubmit(this, _textVideoMemBlitter, tvm);
			rce = m_renderCommandEncoder;

			rce->popDebugGroup();
		}
		else if (_render->m_debug & BGFX_DEBUG_TEXT)
		{
			rce->pushDebugGroup(nsstr("debugtext") );

			dbgTextSubmit(this, _textVideoMemBlitter, _render->m_textVideoMem);
			rce = m_renderCommandEncoder;

			rce->popDebugGroup();
		}

		endEncoding();

		m_renderCommandEncoderFrameBufferHandle = BGFX_INVALID_HANDLE;

		if (_render->m_capture)
		{
			MTL::CaptureManager* captureMgr = getSharedCaptureManager();
			if (captureMgr->isCapturing() )
			{
				captureMgr->stopCapture();
			}
		}

		if (m_screenshotTarget)
		{
			MTL::RenderPassDescriptor* renderPassDescriptor = newRenderPassDescriptor();
			renderPassDescriptor->colorAttachments()->object(0)->setTexture(NULL != m_mainFrameBuffer.m_swapChain ? m_mainFrameBuffer.m_swapChain->currentDrawableTexture() : NULL);
			renderPassDescriptor->colorAttachments()->object(0)->setStoreAction(MTL::StoreActionStore);

			rce = m_commandBuffer->renderCommandEncoder(renderPassDescriptor);

			MTL_RELEASE(renderPassDescriptor, 0);

			if (m_depthClamp)
			{
				rce->setDepthClipMode(MTL::DepthClipModeClamp);
			}

			rce->setCullMode( (MTL::CullMode)MTL::CullModeNone);

			rce->setRenderPipelineState(m_screenshotBlitRenderPipelineState);

			const MTL::SamplerState* samplerState = getSamplerState(0
				| BGFX_SAMPLER_U_CLAMP
				| BGFX_SAMPLER_V_CLAMP
				| BGFX_SAMPLER_MIN_POINT
				| BGFX_SAMPLER_MAG_POINT
				| BGFX_SAMPLER_MIP_POINT
				);

			rce->setFragmentSamplerState(samplerState, 0);
			rce->setFragmentTexture(m_screenshotTarget, 0);

			rce->drawPrimitives(MTL::PrimitiveTypeTriangle, 0, 3, 1);

			rce->endEncoding();
		}

		if (NULL != m_commandBuffer)
		{
			m_cmd.kick(true, false);
			m_commandBuffer = NULL;
		}
	}

} /* namespace mtl */ } // namespace bgfx

#else

namespace bgfx { namespace mtl
	{
		RendererContextI* rendererCreate(const Init& _init)
		{
			BX_UNUSED(_init);
			return NULL;
		}

		void rendererDestroy()
		{
		}
	} /* namespace mtl */ } // namespace bgfx

#endif // BGFX_CONFIG_RENDERER_METAL