From bcfe03c8e1eb3646458faa02b6cceafaa40c1a94 Mon Sep 17 00:00:00 2001
From: Philip Rideout <philiprideout@gmail.com>
Date: Thu, 29 Nov 2018 12:19:20 -0800
Subject: [PATCH] KtxUtility improvements.

This makes it easier for C++ clients to use KTX files and simplifies
the JavaScript bindings.
---
 libs/image/include/image/KtxUtility.h | 29 ++++++++++++++++++++-------
 web/filament-js/jsbindings.cpp        | 17 +++++-----------
 2 files changed, 27 insertions(+), 19 deletions(-)

diff --git a/libs/image/include/image/KtxUtility.h b/libs/image/include/image/KtxUtility.h
index e9927e4f5a..eb55666557 100644
--- a/libs/image/include/image/KtxUtility.h
+++ b/libs/image/include/image/KtxUtility.h
@@ -28,6 +28,7 @@ namespace KtxUtility {
     using TextureFormat = filament::driver::TextureFormat;
     using CompressedPixelDataType = filament::driver::CompressedPixelDataType;
     using PixelDataType = filament::driver::PixelDataType;
+    using PixelDataFormat = filament::driver::PixelDataFormat;
 
     template<typename T>
     T toCompressedFilamentEnum(uint32_t format) {
@@ -78,12 +79,12 @@ namespace KtxUtility {
         return (T) 0xffff;
     }
 
-    CompressedPixelDataType toCompressedPixelDataType(uint32_t format) {
-        return toCompressedFilamentEnum<CompressedPixelDataType>(format);
+    CompressedPixelDataType toCompressedPixelDataType(const KtxInfo& info) {
+        return toCompressedFilamentEnum<CompressedPixelDataType>(info.glInternalFormat);
     }
 
-    PixelDataType toPixelDataType(uint32_t dtype) {
-        switch (dtype) {
+    PixelDataType toPixelDataType(const KtxInfo& info) {
+        switch (info.glType) {
             case KtxBundle::UNSIGNED_BYTE: return PixelDataType::UBYTE;
             case KtxBundle::UNSIGNED_SHORT: return PixelDataType::USHORT;
             case KtxBundle::HALF_FLOAT: return PixelDataType::HALF;
@@ -92,8 +93,22 @@ namespace KtxUtility {
         return (PixelDataType) 0xff;
     }
 
-    TextureFormat toTextureFormat(uint32_t format) {
-        switch (format) {
+    PixelDataFormat toPixelDataFormat(const KtxInfo& info, bool rgbm = false) {
+        switch (info.glTypeSize) {
+            case 1: return PixelDataFormat::R;
+            case 2: return PixelDataFormat::RG;
+            case 3: return PixelDataFormat::RGB;
+            case 4: return rgbm ? PixelDataFormat::RGBM : PixelDataFormat::RGBA;
+        }
+        return (PixelDataFormat) 0xff;
+    }
+
+    bool isCompressed(const KtxInfo& info) {
+        return info.glFormat == 0;
+    }
+
+    TextureFormat toTextureFormat(const KtxInfo& info) {
+        switch (info.glInternalFormat) {
             case KtxBundle::RED: return TextureFormat::R8;
             case KtxBundle::RG: return TextureFormat::RG8;
             case KtxBundle::RGB: return TextureFormat::RGB8;
@@ -153,7 +168,7 @@ namespace KtxUtility {
             case KtxBundle::RGBA32UI: return TextureFormat::RGBA32UI;
             case KtxBundle::RGBA32I: return TextureFormat::RGBA32I;
         }
-        return toCompressedFilamentEnum<TextureFormat>(format);
+        return toCompressedFilamentEnum<TextureFormat>(info.glInternalFormat);
     }
 
 } // namespace KtxUtility
diff --git a/web/filament-js/jsbindings.cpp b/web/filament-js/jsbindings.cpp
index 91b7dc0613..79947b1ce5 100644
--- a/web/filament-js/jsbindings.cpp
+++ b/web/filament-js/jsbindings.cpp
@@ -787,7 +787,7 @@ class_<KtxBundle>("KtxBundle")
     /// Returns "undefined" if no valid Filament enumerant exists.
     .function("getInternalFormat",
             EMBIND_LAMBDA(Texture::InternalFormat, (KtxBundle* self, bool srgb), {
-        auto result = KtxUtility::toTextureFormat(self->info().glInternalFormat);
+        auto result = KtxUtility::toTextureFormat(self->info());
         if (srgb) {
             if (result == Texture::InternalFormat::RGB8) {
                 result = Texture::InternalFormat::SRGB8;
@@ -805,14 +805,7 @@ class_<KtxBundle>("KtxBundle")
     /// Returns "undefined" if no valid Filament enumerant exists.
     .function("getPixelDataFormat",
             EMBIND_LAMBDA(driver::PixelDataFormat, (KtxBundle* self, bool rgbm), {
-        switch (self->info().glTypeSize) {
-            case 1: return driver::PixelDataFormat::R;
-            case 2: return driver::PixelDataFormat::RG;
-            case 3: return driver::PixelDataFormat::RGB;
-            case 4: return rgbm ? driver::PixelDataFormat::RGBA : driver::PixelDataFormat::RGBM;
-        }
-        assert(false && "Unknown pixel data format.");
-        return (driver::PixelDataFormat) 0xff;
+        return KtxUtility::toPixelDataFormat(self->getInfo());
     }), allow_raw_pointers())
 
     /// getPixelDataType ::method::
@@ -820,7 +813,7 @@ class_<KtxBundle>("KtxBundle")
     /// Returns "undefined" if no valid Filament enumerant exists.
     .function("getPixelDataType",
             EMBIND_LAMBDA(driver::PixelDataType, (KtxBundle* self), {
-        return KtxUtility::toPixelDataType(self->info().glType);
+        return KtxUtility::toPixelDataType(self->getInfo());
     }), allow_raw_pointers())
 
     /// getCompressedPixelDataType ::method::
@@ -828,14 +821,14 @@ class_<KtxBundle>("KtxBundle")
     /// Returns "undefined" if no valid Filament enumerant exists.
     .function("getCompressedPixelDataType",
             EMBIND_LAMBDA(driver::CompressedPixelDataType, (KtxBundle* self), {
-        return KtxUtility::toCompressedPixelDataType(self->info().glInternalFormat);
+        return KtxUtility::toCompressedPixelDataType(self->getInfo());
     }), allow_raw_pointers())
 
     /// isCompressed ::method::
     /// Per spec, compressed textures in KTX always have their glFormat field set to 0.
     /// ::retval:: boolean
     .function("isCompressed", EMBIND_LAMBDA(bool, (KtxBundle* self), {
-        return self->info().glFormat == 0;
+        return KtxUtility::isCompressed(self->getInfo());
     }), allow_raw_pointers())
 
     .function("isCubemap", &KtxBundle::isCubemap)