// basisu_gpu_texture.h // Copyright (C) 2019-2026 Binomial LLC. All Rights Reserved. // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #pragma once #include "../transcoder/basisu.h" #include "../transcoder/basisu_astc_helpers.h" #include "basisu_etc.h" // Forward declarations for transcode_ktx2_to_dds() below. The full transcoder // header is only included by basisu_gpu_texture.cpp, keeping this header light. // (transcoder_texture_format is a plain int-backed enum class, so an opaque // forward declaration is valid here.) namespace basist { class ktx2_transcoder; enum class transcoder_texture_format; enum class dds_format; } namespace basisu { // GPU texture "image" class gpu_image { public: enum { cMaxBlockSize = 12 }; gpu_image() { clear(); } gpu_image(texture_format fmt, uint32_t width, uint32_t height) { init(fmt, width, height); } void clear() { m_fmt = texture_format::cInvalidTextureFormat; m_width = 0; m_height = 0; m_block_width = 0; m_block_height = 0; m_blocks_x = 0; m_blocks_y = 0; m_qwords_per_block = 0; m_blocks.clear(); } inline texture_format get_format() const { return m_fmt; } inline bool is_hdr() const { return is_hdr_texture_format(m_fmt); } inline bool is_ldr() const { return !is_hdr_texture_format(m_fmt); } // Width/height in pixels inline uint32_t get_pixel_width() const { return m_width; } inline uint32_t get_pixel_height() const { return m_height; } // Width/height in blocks, row pitch is assumed to be m_blocks_x. inline uint32_t get_blocks_x() const { return m_blocks_x; } inline uint32_t get_blocks_y() const { return m_blocks_y; } // Size of each block in pixels inline uint32_t get_block_width() const { return m_block_width; } inline uint32_t get_block_height() const { return m_block_height; } inline uint32_t get_qwords_per_block() const { return m_qwords_per_block; } inline uint32_t get_total_blocks() const { return m_blocks_x * m_blocks_y; } inline uint32_t get_bytes_per_block() const { return get_qwords_per_block() * sizeof(uint64_t); } inline uint32_t get_row_pitch_in_bytes() const { return get_bytes_per_block() * get_blocks_x(); } inline const uint64_vec &get_blocks() const { return m_blocks; } inline const uint64_t *get_ptr() const { return &m_blocks[0]; } inline uint64_t *get_ptr() { return &m_blocks[0]; } inline uint32_t get_size_in_bytes() const { return get_total_blocks() * get_qwords_per_block() * sizeof(uint64_t); } inline const void *get_block_ptr(uint32_t block_x, uint32_t block_y, uint32_t element_index = 0) const { assert(block_x < m_blocks_x && block_y < m_blocks_y); return &m_blocks[(block_x + block_y * m_blocks_x) * m_qwords_per_block + element_index]; } inline void *get_block_ptr(uint32_t block_x, uint32_t block_y, uint32_t element_index = 0) { assert(block_x < m_blocks_x && block_y < m_blocks_y && element_index < m_qwords_per_block); return &m_blocks[(block_x + block_y * m_blocks_x) * m_qwords_per_block + element_index]; } void init(texture_format fmt, uint32_t width, uint32_t height) { m_fmt = fmt; m_width = width; m_height = height; m_block_width = basisu::get_block_width(m_fmt); m_block_height = basisu::get_block_height(m_fmt); m_blocks_x = (m_width + m_block_width - 1) / m_block_width; m_blocks_y = (m_height + m_block_height - 1) / m_block_height; m_qwords_per_block = basisu::get_qwords_per_block(m_fmt); m_blocks.resize(0); m_blocks.resize(m_blocks_x * m_blocks_y * m_qwords_per_block); } // Unpacks LDR textures only. Asserts and returns false otherwise. // astc_srgb: true to use the ASTC sRGB decode profile, false for linear. // For XUASTC LDR, this should match what was used during encoding. For ETC1S/UASTC LDR 4x4, this should be false. bool unpack(image& img, bool astc_srgb) const; // Unpacks HDR textures only. Asserts and returns false otherwise. bool unpack_hdr(imagef& img) const; inline void override_dimensions(uint32_t w, uint32_t h) { m_width = w; m_height = h; } private: texture_format m_fmt; uint32_t m_width, m_height, m_blocks_x, m_blocks_y, m_block_width, m_block_height, m_qwords_per_block; uint64_vec m_blocks; }; typedef basisu::vector gpu_image_vec; // A mip chain (or single image) of uncompressed RGBA images. Used by // write_uncompressed_rgba32_dds() as one array slice / cubemap face. typedef basisu::vector image_vec; // KTX1 file writing - compatible with ARM's astcenc tool, and some other tools. // Note astc_linear_flag used to be always effectively true in older code. It's ignored for ASTC HDR formats. bool create_ktx_texture_file(uint8_vec &ktx_data, const basisu::vector& gpu_images, bool cubemap_flag, bool astc_srgb_flag); bool does_dds_support_format(texture_format fmt); // Returns true if create_ktx_texture_file() can write this (compressed) texture // format. Mirrors that writer's supported set, minus the formats we don't expose // for KTX export right now (ATC, FXT1, and all uncompressed formats). bool does_ktx_support_format(texture_format fmt); bool write_dds_file(uint8_vec& dds_data, const basisu::vector& gpu_images, bool cubemap_flag, bool use_srgb_format); bool write_dds_file(const char* pFilename, const basisu::vector& gpu_images, bool cubemap_flag, bool use_srgb_format); // Writes uncompressed 32-bit RGBA image data to an in-memory .DDS blob. // images is indexed [array-slice][mip level]. For cubemaps and cubemap arrays // the outer slice count must be a multiple of 6, ordered layer-major then the // six faces, and cubemap_flag must be true; for 2D textures and 2D arrays // cubemap_flag is false and the outer count is the array size (1 for a plain // 2D texture). Every slice must have the same mip count and the same level-0 // dimensions, and each mip level must be floor(prev/2) (min 1). Supports 2D, // 2D arrays, cubemaps, and cubemap arrays, with or without a mip chain. // Validates all of the above; returns false (and clears dds_data) on any // inconsistency or write failure. Reusable on its own (a sibling to // write_dds_file for the uncompressed RGBA case). bool write_uncompressed_rgba32_dds(uint8_vec& dds_data, const basisu::vector& images, bool cubemap_flag, bool use_srgb_format); // Transcodes the entire contents of an init()'d ktx2_transcoder (every mip // level, array layer, and cubemap face) to fmt and serializes a Microsoft // .DDS (DirectDraw Surface) blob into dds_data. fmt MUST be one of the DirectX // BC formats writable to DDS (cTFBC1_RGB, cTFBC3_RGBA, cTFBC4_R, cTFBC5_RG, // cTFBC6H, cTFBC7_RGBA) or uncompressed cTFRGBA32; any other format fails. // Supports 2D, 2D arrays, cubemaps, and cubemap arrays (with or without mips). // The transcoder need only have been init()'d -- this calls start_transcoding() // itself. Returns false (and clears dds_data) on any error. // srgb_mode selects whether the sRGB DDS format variants are used: -1 = auto // (follow the KTX2's transfer function via transcoder.is_srgb()), 0 = force // linear/UNORM, 1 = force sRGB. Ignored for formats that have no sRGB variant // (BC4/BC5/BC6H/etc.). decode_flags is passed straight to // ktx2_transcoder::transcode_image_level() (a cDecodeFlags* bitmask), letting the // caller control the transcode -- e.g. force/disable deblocking, high quality, etc. bool transcode_ktx2_to_dds(basist::ktx2_transcoder& transcoder, basist::transcoder_texture_format fmt, uint8_vec& dds_data, int srgb_mode = -1, uint32_t decode_flags = 0); // Like transcode_ktx2_to_dds(), but serializes a KTX1 (.ktx) file instead, via // create_ktx_texture_file(). COMPRESSED formats only -- BC1-7, ETC1/ETC2, // ETC2 EAC R11/RG11, PVRTC1, PVRTC2 (RGBA), ASTC LDR/HDR, UASTC; uncompressed // (RGBA32/half/float) is not supported here yet. fmt must pass // does_ktx_support_format(). Supports 2D, 2D arrays, cubemaps, and cubemap // arrays (with or without mips). srgb_mode is as above; it selects the sRGB GL // enum variants for the formats that have them (BC1/BC3/BC7, ETC2, PVRTC1, ASTC LDR) // and is ignored for formats with no sRGB variant (BC4/BC5/BC6H/ETC1/PVRTC2). decode_flags is // passed straight to transcode_image_level() (a cDecodeFlags* bitmask). The // transcoder need only have been init()'d. Returns false (and clears ktx_data) // on any error. bool transcode_ktx2_to_ktx(basist::ktx2_transcoder& transcoder, basist::transcoder_texture_format fmt, uint8_vec& ktx_data, int srgb_mode = -1, uint32_t decode_flags = 0); // Currently reads 2D 32bpp RGBA, 16-bit HALF RGBA, or 32-bit FLOAT RGBA, with or without mipmaps. No tex arrays or cubemaps, yet. bool read_uncompressed_dds_file(const char* pFilename, basisu::vector& ldr_mips, basisu::vector& hdr_mips); // Cracks open a .DDS file with tinydds (header only -- no pixel decode) and // prints its high-level info to stdout: texture type (2D / 2D array / cubemap / // cubemap array / 3D), dimensions, mip level count, array slice count, and the // format (a friendly name for BC1-7 and the common LDR/HDR uncompressed formats, // otherwise the raw hex value). Intended as a quick development sanity check. bool print_dds_info(const char* pFilename); // Reads a KTX1 (.ktx) file's 64-byte header (endian-swapping the fields if the // file's endianness marker says so) and prints them to stdout: GL type/format/ // internalFormat (+ a friendly name for the common compressed formats), // dimensions, array elements, faces, mip levels, and key-value-data size. Header // only -- it does not parse the key/value data or image data. Development aid. bool print_ktx_info(const char* pFilename); // Supports DDS and KTX bool write_compressed_texture_file(const char *pFilename, const basisu::vector& g, bool cubemap_flag, bool use_srgb_format); bool write_compressed_texture_file(const char* pFilename, const gpu_image_vec& g, bool use_srgb_format); bool write_compressed_texture_file(const char *pFilename, const gpu_image &g, bool use_srgb_format); bool write_3dfx_out_file(const char* pFilename, const gpu_image& gi); // Returns the ASCII name of a texture_format enum value, e.g. "BC7", "ASTC_LDR_4x4", "ETC1". const char* get_texture_format_name(texture_format fmt); // Human-readable name for the exact physical format stored in a .DDS file (basist::dds_transcoder::get_dds_format()). const char* get_dds_format_string(basist::dds_format fmt); // GPU texture block unpacking // For ETC1, use in basisu_etc.h: bool unpack_etc1(const etc_block& block, color_rgba *pDst, bool preserve_alpha) void unpack_etc2_eac(const void *pBlock_bits, color_rgba *pPixels); bool unpack_bc6h(const void* pSrc_block, void* pDst_block, bool is_signed, uint32_t dest_pitch_in_halfs = 4 * 3); // full format, outputs HALF values, RGB texels only (not RGBA) void unpack_atc(const void* pBlock_bits, color_rgba* pPixels); // We only support CC_MIXED non-alpha blocks here because that's the only mode the transcoder uses at the moment. bool unpack_fxt1(const void* p, color_rgba* pPixels); // PVRTC2 is currently limited to only what our transcoder outputs (non-interpolated, hard_flag=1 modulation=0). In this mode, PVRTC2 looks much like BC1/ATC. bool unpack_pvrtc2(const void* p, color_rgba* pPixels); void unpack_etc2_eac_r(const void *p, color_rgba* pPixels, uint32_t c); void unpack_etc2_eac_rg(const void* p, color_rgba* pPixels); // unpack_block() is primarily intended to unpack texture data created by the transcoder. // For some texture formats (like ETC2 RGB, PVRTC2, FXT1) it's not yet a complete implementation. // Unpacks LDR texture formats only. bool unpack_block(texture_format fmt, const void *pBlock, color_rgba *pPixels, bool astc_srgb); // Unpacks HDR texture formats only. bool unpack_block_hdr(texture_format fmt, const void* pBlock, vec4F* pPixels); bool read_astc_file(const uint8_t* pImage_data, size_t image_data_size, vector2D& blocks, uint32_t& block_width, uint32_t& block_height, uint32_t& width, uint32_t& height); bool read_astc_file(const char* pFilename, vector2D& blocks, uint32_t& block_width, uint32_t& block_height, uint32_t& width, uint32_t& height); bool write_astc_file(const char* pFilename, const void* pBlocks, uint32_t block_width, uint32_t block_height, uint32_t dim_x, uint32_t dim_y); } // namespace basisu