Source/core/platform/graphics/GraphicsContext3D.cpp - Issue 13842017: Add OES_texture_half_float extension support in WebGL.

Unified Diff: Source/core/platform/graphics/GraphicsContext3D.cpp

Issue 13842017: Add OES_texture_half_float extension support in WebGL. (Closed) Base URL: https://chromium.googlesource.com/chromium/blink.git@master

Patch Set: move test cases to directory LayoutTest/webgl/ Created 7 years, 8 months ago

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Index: Source/core/platform/graphics/GraphicsContext3D.cpp

diff --git a/Source/core/platform/graphics/GraphicsContext3D.cpp b/Source/core/platform/graphics/GraphicsContext3D.cpp

index e82d7f18c9e4f378493f62b5366e79fb85ec3571..cc012f34be93bba11812bd2b3b376350288beb9c 100644

--- a/Source/core/platform/graphics/GraphicsContext3D.cpp

+++ b/Source/core/platform/graphics/GraphicsContext3D.cpp

@@ -89,6 +89,27 @@ GraphicsContext3D::DataFormat getDataFormat(GC3Denum destinationFormat, GC3Denum

case GraphicsContext3D::UNSIGNED_SHORT_5_6_5:

dstFormat = GraphicsContext3D::DataFormatRGB565;

break;

+ case GraphicsContext3D::HALF_FLOAT_OES: // OES_texture_half_float

+ switch (destinationFormat) {

+ case GraphicsContext3D::RGB:

+ dstFormat = GraphicsContext3D::DataFormatRGB16F;

+ break;

+ case GraphicsContext3D::RGBA:

+ dstFormat = GraphicsContext3D::DataFormatRGBA16F;

+ break;

+ case GraphicsContext3D::ALPHA:

+ dstFormat = GraphicsContext3D::DataFormatA16F;

+ break;

+ case GraphicsContext3D::LUMINANCE:

+ dstFormat = GraphicsContext3D::DataFormatR16F;

+ break;

+ case GraphicsContext3D::LUMINANCE_ALPHA:

+ dstFormat = GraphicsContext3D::DataFormatRA16F;

+ break;

+ default:

+ ASSERT_NOT_REACHED();

+ }

+ break;

case GraphicsContext3D::FLOAT: // OES_texture_float

switch (destinationFormat) {

case GraphicsContext3D::RGB:

@@ -130,6 +151,129 @@ void getDrawingParameters(DrawingBuffer* drawingBuffer, WebKit::WebGraphicsConte

}

+// Following Float to Half-Float converion code is from the implementation of ftp://www.fox-toolkit.org/pub/fasthalffloatconversion.pdf,

+// "Fast Half Float Conversions" by Jeroen van der Zijp, November 2008 (Revised September 2010).

+// Specially, the basetable[512] and shifttable[512] are generated as follows:

+/*

+unsigned short basetable[512];

+unsigned char shifttable[512];

+void generatetables(){

+ unsigned int i;

+ int e;

+ for (i = 0; i < 256; ++i){

+ e = i - 127;

+ if (e < -24){ // Very small numbers map to zero

+ basetable[i | 0x000] = 0x0000;

+ basetable[i | 0x100] = 0x8000;

+ shifttable[i | 0x000] = 24;

+ shifttable[i | 0x100] = 24;

+ }

+ else if (e < -14) { // Small numbers map to denorms

+ basetable[i | 0x000] = (0x0400>>(-e-14));

+ basetable[i | 0x100] = (0x0400>>(-e-14)) | 0x8000;

+ shifttable[i | 0x000] = -e-1;

+ shifttable[i | 0x100] = -e-1;

+ }

+ else if (e <= 15){ // Normal numbers just lose precision

+ basetable[i | 0x000] = ((e+15)<<10);

+ basetable[i| 0x100] = ((e+15)<<10) | 0x8000;

+ shifttable[i|0x000] = 13;

+ shifttable[i|0x100] = 13;

+ }

+ else if (e<128){ // Large numbers map to Infinity

+ basetable[i|0x000] = 0x7C00;

+ basetable[i|0x100] = 0xFC00;

+ shifttable[i|0x000] = 24;

+ shifttable[i|0x100] = 24;

+ }

+ else { // Infinity and NaN's stay Infinity and NaN's

+ basetable[i|0x000] = 0x7C00;

+ basetable[i|0x100] = 0xFC00;

+ shifttable[i|0x000] = 13;

+ shifttable[i|0x100] = 13;

+ }

+*/

+unsigned short baseTable[512] = {

+0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

+0, 0, 0, 0, 0, 0, 0, 1, 2, 4, 8, 16, 32, 64, 128, 256,

+512, 1024, 2048, 3072, 4096, 5120, 6144, 7168, 8192, 9216, 10240, 11264, 12288, 13312, 14336, 15360,

+16384, 17408, 18432, 19456, 20480, 21504, 22528, 23552, 24576, 25600, 26624, 27648, 28672, 29696, 30720, 31744,

+31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744, 31744,

+32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768, 32768,

+32768, 32768, 32768, 32768, 32768, 32768, 32768, 32769, 32770, 32772, 32776, 32784, 32800, 32832, 32896, 33024,

+33280, 33792, 34816, 35840, 36864, 37888, 38912, 39936, 40960, 41984, 43008, 44032, 45056, 46080, 47104, 48128,

+49152, 50176, 51200, 52224, 53248, 54272, 55296, 56320, 57344, 58368, 59392, 60416, 61440, 62464, 63488, 64512,

+64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512,

+64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512, 64512

+};

+unsigned char shiftTable[512] = {

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,

+24, 24, 24, 24, 24, 24, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15,

+14, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,

+13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 24,

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 13,

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,

+24, 24, 24, 24, 24, 24, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15,

+14, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13,

+13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 13, 24,

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24,

+24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 24, 13

+};

+unsigned short convertFloatToHalfFloat(float f)

+ unsigned temp = *(reinterpret_cast<unsigned *>(&f));

+ unsigned signexp = (temp >> 23) & 0x1ff;

+ return baseTable[signexp] + ((temp & 0x007fffff) >> shiftTable[signexp]);

} // anonymous namespace

// Macros to assist in delegating from GraphicsContext3D to

@@ -1621,17 +1765,163 @@ template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRA32F, GraphicsC

}

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGBA16F, GraphicsContext3D::AlphaDoNothing, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ destination[0] = convertFloatToHalfFloat(source[0]);

+ destination[1] = convertFloatToHalfFloat(source[1]);

+ destination[2] = convertFloatToHalfFloat(source[2]);

+ destination[3] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 4;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGBA16F, GraphicsContext3D::AlphaDoPremultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3];

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[1] * scaleFactor);

+ destination[2] = convertFloatToHalfFloat(source[2] * scaleFactor);

+ destination[3] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 4;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGBA16F, GraphicsContext3D::AlphaDoUnmultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3] ? 1.0f / source[3] : 1.0f;

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[1] * scaleFactor);

+ destination[2] = convertFloatToHalfFloat(source[2] * scaleFactor);

+ destination[3] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 4;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGB16F, GraphicsContext3D::AlphaDoNothing, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ destination[0] = convertFloatToHalfFloat(source[0]);

+ destination[1] = convertFloatToHalfFloat(source[1]);

+ destination[2] = convertFloatToHalfFloat(source[2]);

+ source += 4;

+ destination += 3;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGB16F, GraphicsContext3D::AlphaDoPremultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3];

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[1] * scaleFactor);

+ destination[2] = convertFloatToHalfFloat(source[2] * scaleFactor);

+ source += 4;

+ destination += 3;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRGB16F, GraphicsContext3D::AlphaDoUnmultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3] ? 1.0f / source[3] : 1.0f;

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[1] * scaleFactor);

+ destination[2] = convertFloatToHalfFloat(source[2] * scaleFactor);

+ source += 4;

+ destination += 3;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRA16F, GraphicsContext3D::AlphaDoNothing, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ destination[0] = convertFloatToHalfFloat(source[0]);

+ destination[1] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 2;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRA16F, GraphicsContext3D::AlphaDoPremultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3];

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 2;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatRA16F, GraphicsContext3D::AlphaDoUnmultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3] ? 1.0f / source[3] : 1.0f;

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ destination[1] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 2;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatR16F, GraphicsContext3D::AlphaDoNothing, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ destination[0] = convertFloatToHalfFloat(source[0]);

+ source += 4;

+ destination += 1;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatR16F, GraphicsContext3D::AlphaDoPremultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3];

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ source += 4;

+ destination += 1;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatR16F, GraphicsContext3D::AlphaDoUnmultiply, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ float scaleFactor = source[3] ? 1.0f / source[3] : 1.0f;

+ destination[0] = convertFloatToHalfFloat(source[0] * scaleFactor);

+ source += 4;

+ destination += 1;

+ }

+template<> ALWAYS_INLINE void pack<GraphicsContext3D::DataFormatA16F, GraphicsContext3D::AlphaDoNothing, float, uint16_t>(const float* source, uint16_t* destination, unsigned pixelsPerRow)

+ for (unsigned i = 0; i < pixelsPerRow; ++i) {

+ destination[0] = convertFloatToHalfFloat(source[3]);

+ source += 4;

+ destination += 1;

+ }

ALWAYS_INLINE bool HasAlpha(int format)

{

return format == GraphicsContext3D::DataFormatA8

+ || format == GraphicsContext3D::DataFormatA16F

|| format == GraphicsContext3D::DataFormatA32F

|| format == GraphicsContext3D::DataFormatRA8

|| format == GraphicsContext3D::DataFormatAR8

+ || format == GraphicsContext3D::DataFormatRA16F

|| format == GraphicsContext3D::DataFormatRA32F

|| format == GraphicsContext3D::DataFormatRGBA8

|| format == GraphicsContext3D::DataFormatBGRA8

|| format == GraphicsContext3D::DataFormatARGB8

|| format == GraphicsContext3D::DataFormatABGR8

+ || format == GraphicsContext3D::DataFormatRGBA16F

|| format == GraphicsContext3D::DataFormatRGBA32F

|| format == GraphicsContext3D::DataFormatRGBA4444

|| format == GraphicsContext3D::DataFormatRGBA5551;

@@ -1640,8 +1930,10 @@ ALWAYS_INLINE bool HasAlpha(int format)

ALWAYS_INLINE bool HasColor(int format)

{

return format == GraphicsContext3D::DataFormatRGBA8

+ || format == GraphicsContext3D::DataFormatRGBA16F

|| format == GraphicsContext3D::DataFormatRGBA32F

|| format == GraphicsContext3D::DataFormatRGB8

+ || format == GraphicsContext3D::DataFormatRGB16F

|| format == GraphicsContext3D::DataFormatRGB32F

|| format == GraphicsContext3D::DataFormatBGR8

|| format == GraphicsContext3D::DataFormatBGRA8

@@ -1651,8 +1943,10 @@ ALWAYS_INLINE bool HasColor(int format)

|| format == GraphicsContext3D::DataFormatRGBA4444

|| format == GraphicsContext3D::DataFormatRGB565

|| format == GraphicsContext3D::DataFormatR8

+ || format == GraphicsContext3D::DataFormatR16F

|| format == GraphicsContext3D::DataFormatR32F

|| format == GraphicsContext3D::DataFormatRA8

+ || format == GraphicsContext3D::DataFormatRA16F

|| format == GraphicsContext3D::DataFormatRA32F

|| format == GraphicsContext3D::DataFormatAR8;

}

@@ -1668,6 +1962,16 @@ struct IsFloatFormat {

};

template<int Format>

+struct IsHalfFloatFormat {

+ static const bool Value =

+ Format == GraphicsContext3D::DataFormatRGBA16F

+ || Format == GraphicsContext3D::DataFormatRGB16F

+ || Format == GraphicsContext3D::DataFormatRA16F

+ || Format == GraphicsContext3D::DataFormatR16F

+ || Format == GraphicsContext3D::DataFormatA16F;

+};

+template<int Format>

struct Is16bppFormat {

static const bool Value =

Format == GraphicsContext3D::DataFormatRGBA5551

@@ -1675,24 +1979,29 @@ struct Is16bppFormat {

|| Format == GraphicsContext3D::DataFormatRGB565;

};

-template<int Format, bool IsFloat = IsFloatFormat<Format>::Value, bool Is16bpp = Is16bppFormat<Format>::Value>

+template<int Format, bool IsFloat = IsFloatFormat<Format>::Value, bool IsHalfFloat = IsHalfFloatFormat<Format>::Value, bool Is16bpp = Is16bppFormat<Format>::Value>

struct DataTypeForFormat {

typedef uint8_t Type;

};

template<int Format>

-struct DataTypeForFormat<Format, true, false> {

+struct DataTypeForFormat<Format, true, false, false> {

typedef float Type;

};

template<int Format>

-struct DataTypeForFormat<Format, false, true> {

+struct DataTypeForFormat<Format, false, true, false> {

+ typedef uint16_t Type;

+};

+template<int Format>

+struct DataTypeForFormat<Format, false, false, true> {

typedef uint16_t Type;

};

template<int Format>

struct IntermediateFormat {

- static const int Value = IsFloatFormat<Format>::Value ? GraphicsContext3D::DataFormatRGBA32F : GraphicsContext3D::DataFormatRGBA8;

+ static const int Value = (IsFloatFormat<Format>::Value || IsHalfFloatFormat<Format>::Value) ? GraphicsContext3D::DataFormatRGBA32F : GraphicsContext3D::DataFormatRGBA8;

};

ALWAYS_INLINE unsigned TexelBytesForFormat(GraphicsContext3D::DataFormat format)

@@ -1706,6 +2015,8 @@ ALWAYS_INLINE unsigned TexelBytesForFormat(GraphicsContext3D::DataFormat format)

case GraphicsContext3D::DataFormatRGBA5551:

case GraphicsContext3D::DataFormatRGBA4444:

case GraphicsContext3D::DataFormatRGB565:

+ case GraphicsContext3D::DataFormatA16F:

+ case GraphicsContext3D::DataFormatR16F:

return 2;

case GraphicsContext3D::DataFormatRGB8:

case GraphicsContext3D::DataFormatBGR8:

@@ -1716,8 +2027,12 @@ ALWAYS_INLINE unsigned TexelBytesForFormat(GraphicsContext3D::DataFormat format)

case GraphicsContext3D::DataFormatBGRA8:

case GraphicsContext3D::DataFormatR32F:

case GraphicsContext3D::DataFormatA32F:

+ case GraphicsContext3D::DataFormatRA16F:

return 4;

+ case GraphicsContext3D::DataFormatRGB16F:

+ return 6;

case GraphicsContext3D::DataFormatRA32F:

+ case GraphicsContext3D::DataFormatRGBA16F:

return 8;

case GraphicsContext3D::DataFormatRGB32F:

return 12;

@@ -1803,17 +2118,22 @@ ALWAYS_INLINE void FormatConverter::convert(GraphicsContext3D::DataFormat dstFor

switch (dstFormat) {

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatR8)

- FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatA8)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatR16F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatR32F)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatA8)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatA16F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatA32F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRA8)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRA16F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRA32F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGB8)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGB565)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGB16F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGB32F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGBA8)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGBA5551)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGBA4444)

+ FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGBA16F)

FORMATCONVERTER_CASE_DSTFORMAT(GraphicsContext3D::DataFormatRGBA32F)

default:

ASSERT_NOT_REACHED();

@@ -1875,7 +2195,7 @@ ALWAYS_INLINE void FormatConverter::convert()

typedef typename DataTypeForFormat<IntermediateSrcFormat>::Type IntermediateSrcType;

const ptrdiff_t srcStrideInElements = m_srcStride / sizeof(SrcType);

const ptrdiff_t dstStrideInElements = m_dstStride / sizeof(DstType);

- const bool trivialUnpack = (SrcFormat == GraphicsContext3D::DataFormatRGBA8 && !IsFloatFormat<DstFormat>::Value) || SrcFormat == GraphicsContext3D::DataFormatRGBA32F;

+ const bool trivialUnpack = (SrcFormat == GraphicsContext3D::DataFormatRGBA8 && !IsFloatFormat<DstFormat>::Value && !IsHalfFloatFormat<DstFormat>::Value) || SrcFormat == GraphicsContext3D::DataFormatRGBA32F;

const bool trivialPack = (DstFormat == GraphicsContext3D::DataFormatRGBA8 || DstFormat == GraphicsContext3D::DataFormatRGBA32F) && alphaOp == GraphicsContext3D::AlphaDoNothing && m_dstStride > 0;

ASSERT(!trivialUnpack || !trivialPack);

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