Quelle  formatutils.cpp   Sprache: C

//
// Copyright 2013 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

// formatutils.cpp: Queries for GL image formats.

#include "libANGLE/formatutils.h"

#include "anglebase/no_destructor.h"
#include "common/mathutil.h"
#include "gpu_info_util/SystemInfo.h"
#include "libANGLE/Context.h"
#include "libANGLE/Framebuffer.h"

using namespace angle;

namespace gl
{

// ES2 requires that format is equal to internal format at all glTex*Image2D entry points and the
// implementation can decide the true, sized, internal format. The ES2FormatMap determines the
// internal format for all valid format and type combinations.
GLenum GetSizedFormatInternal(GLenum format, GLenum type);

namespace
{
bool CheckedMathResult(const CheckedNumeric<GLuint> &value, GLuint *resultOut)
{
    if (!value.IsValid())
    {
        return false;
    }
    else
    {
        *resultOut = value.ValueOrDie();
        return true;
    }
}

constexpr uint32_t PackTypeInfo(GLuint bytes, bool specialized)
{
    // static_assert within constexpr requires c++17
    // static_assert(isPow2(bytes));
    return bytes | (rx::Log2(bytes) << 8) | (specialized << 16);
}

}  // anonymous namespace

FormatType::FormatType() : format(GL_NONE), type(GL_NONE) {}

FormatType::FormatType(GLenum format_, GLenum type_) : format(format_), type(type_) {}

bool FormatType::operator<(const FormatType &other) const
{
    if (format != other.format)
        return format < other.format;
    return type < other.type;
}

bool operator<(const Type &a, const Type &b)
{
    return memcmp(&a, &b, sizeof(Type)) < 0;
}

// Information about internal formats
static bool AlwaysSupported(const Version &, const Extensions &)
{
    return true;
}

static bool NeverSupported(const Version &, const Extensions &)
{
    return false;
}

static bool RequireES1(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion.major == 1;
}

template <GLuint minCoreGLMajorVersion, GLuint minCoreGLMinorVersion>
static bool RequireES(const Version &clientVersion, const Extensions &)
{
    return clientVersion >= Version(minCoreGLMajorVersion, minCoreGLMinorVersion);
}

// Check support for a single extension
template <ExtensionBool bool1>
static bool RequireExt(const Version &, const Extensions &extensions)
{
    return extensions.*bool1;
}

// Check for a minimum client version or a single extension
template <GLuint minCoreGLMajorVersion, GLuint minCoreGLMinorVersion, ExtensionBool bool1>
static bool RequireESOrExt(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(minCoreGLMajorVersion, minCoreGLMinorVersion) ||
           extensions.*bool1;
}

// Check for a minimum client version or two extensions
template <GLuint minCoreGLMajorVersion,
          GLuint minCoreGLMinorVersion,
          ExtensionBool bool1,
          ExtensionBool bool2>
static bool RequireESOrExtAndExt(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(minCoreGLMajorVersion, minCoreGLMinorVersion) ||
           (extensions.*bool1 && extensions.*bool2);
}

// Check for a minimum client version or at least one of two extensions
template <GLuint minCoreGLMajorVersion,
          GLuint minCoreGLMinorVersion,
          ExtensionBool bool1,
          ExtensionBool bool2>
static bool RequireESOrExtOrExt(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(minCoreGLMajorVersion, minCoreGLMinorVersion) ||
           extensions.*bool1 || extensions.*bool2;
}

// Check support for two extensions
template <ExtensionBool bool1, ExtensionBool bool2>
static bool RequireExtAndExt(const Version &, const Extensions &extensions)
{
    return extensions.*bool1 && extensions.*bool2;
}

// Check support for either of two extensions
template <ExtensionBool bool1, ExtensionBool bool2>
static bool RequireExtOrExt(const Version &, const Extensions &extensions)
{
    return extensions.*bool1 || extensions.*bool2;
}

// Check support for any of three extensions
template <ExtensionBool bool1, ExtensionBool bool2, ExtensionBool bool3>
static bool RequireExtOrExtOrExt(const Version &, const Extensions &extensions)
{
    return extensions.*bool1 || extensions.*bool2 || extensions.*bool3;
}

// R8, RG8
static bool SizedRGSupport(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(3, 0) ||
           (extensions.textureStorageEXT && extensions.textureRgEXT);
}

// R16F, RG16F with HALF_FLOAT_OES type
static bool SizedHalfFloatOESRGSupport(const Version &clientVersion, const Extensions &extensions)
{
    return extensions.textureStorageEXT && extensions.textureHalfFloatOES &&
           extensions.textureRgEXT;
}

static bool SizedHalfFloatOESRGTextureAttachmentSupport(const Version &clientVersion,
                                                        const Extensions &extensions)
{
    return SizedHalfFloatOESRGSupport(clientVersion, extensions) &&
           extensions.colorBufferHalfFloatEXT;
}

// R16F, RG16F with either HALF_FLOAT_OES or HALF_FLOAT types
static bool SizedHalfFloatRGSupport(const Version &clientVersion, const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        return true;
    }
    // HALF_FLOAT_OES
    else
    {
        return SizedHalfFloatOESRGSupport(clientVersion, extensions);
    }
}

static bool SizedHalfFloatRGTextureAttachmentSupport(const Version &clientVersion,
                                                     const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        // WebGL 2 supports EXT_color_buffer_half_float.
        return extensions.colorBufferFloatEXT ||
               (extensions.webglCompatibilityANGLE && extensions.colorBufferHalfFloatEXT);
    }
    // HALF_FLOAT_OES
    else
    {
        return SizedHalfFloatOESRGTextureAttachmentSupport(clientVersion, extensions);
    }
}

static bool SizedHalfFloatRGRenderbufferSupport(const Version &clientVersion,
                                                const Extensions &extensions)
{
    return (clientVersion >= Version(3, 0) ||
            (extensions.textureHalfFloatOES && extensions.textureRgEXT)) &&
           (extensions.colorBufferFloatEXT || extensions.colorBufferHalfFloatEXT);
}

// RGB16F, RGBA16F with HALF_FLOAT_OES type
static bool SizedHalfFloatOESSupport(const Version &clientVersion, const Extensions &extensions)
{
    return extensions.textureStorageEXT && extensions.textureHalfFloatOES;
}

static bool SizedHalfFloatOESTextureAttachmentSupport(const Version &clientVersion,
                                                      const Extensions &extensions)
{
    return SizedHalfFloatOESSupport(clientVersion, extensions) &&
           extensions.colorBufferHalfFloatEXT;
}

// RGB16F, RGBA16F with either HALF_FLOAT_OES or HALF_FLOAT types
static bool SizedHalfFloatSupport(const Version &clientVersion, const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        return true;
    }
    // HALF_FLOAT_OES
    else
    {
        return SizedHalfFloatOESSupport(clientVersion, extensions);
    }
}

static bool SizedHalfFloatFilterSupport(const Version &clientVersion, const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        return true;
    }
    // HALF_FLOAT_OES
    else
    {
        return extensions.textureHalfFloatLinearOES;
    }
}

static bool SizedHalfFloatRGBTextureAttachmentSupport(const Version &clientVersion,
                                                      const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        // It is unclear how EXT_color_buffer_half_float applies to ES3.0 and above, however,
        // dEQP GLES3 es3fFboColorbufferTests.cpp verifies that texture attachment of GL_RGB16F
        // is possible, so assume that all GLES implementations support it.
        // The WebGL version of the extension explicitly forbids RGB formats.
        return extensions.colorBufferHalfFloatEXT && !extensions.webglCompatibilityANGLE;
    }
    // HALF_FLOAT_OES
    else
    {
        return SizedHalfFloatOESTextureAttachmentSupport(clientVersion, extensions);
    }
}

static bool SizedHalfFloatRGBRenderbufferSupport(const Version &clientVersion,
                                                 const Extensions &extensions)
{
    return !extensions.webglCompatibilityANGLE &&
           ((clientVersion >= Version(3, 0) || extensions.textureHalfFloatOES) &&
            extensions.colorBufferHalfFloatEXT);
}

static bool SizedHalfFloatRGBATextureAttachmentSupport(const Version &clientVersion,
                                                       const Extensions &extensions)
{
    // HALF_FLOAT
    if (clientVersion >= Version(3, 0))
    {
        // WebGL 2 supports EXT_color_buffer_half_float.
        return extensions.colorBufferFloatEXT ||
               (extensions.webglCompatibilityANGLE && extensions.colorBufferHalfFloatEXT);
    }
    // HALF_FLOAT_OES
    else
    {
        return SizedHalfFloatOESTextureAttachmentSupport(clientVersion, extensions);
    }
}

static bool SizedHalfFloatRGBARenderbufferSupport(const Version &clientVersion,
                                                  const Extensions &extensions)
{
    return (clientVersion >= Version(3, 0) || extensions.textureHalfFloatOES) &&
           (extensions.colorBufferFloatEXT || extensions.colorBufferHalfFloatEXT);
}

// R32F, RG32F
static bool SizedFloatRGSupport(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(3, 0) ||
           (extensions.textureStorageEXT && extensions.textureFloatOES && extensions.textureRgEXT);
}

// RGB32F
static bool SizedFloatRGBSupport(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(3, 0) ||
           (extensions.textureStorageEXT && extensions.textureFloatOES) ||
           extensions.colorBufferFloatRgbCHROMIUM;
}

// RGBA32F
static bool SizedFloatRGBASupport(const Version &clientVersion, const Extensions &extensions)
{
    return clientVersion >= Version(3, 0) ||
           (extensions.textureStorageEXT && extensions.textureFloatOES) ||
           extensions.colorBufferFloatRgbaCHROMIUM;
}

static bool SizedFloatRGBARenderableSupport(const Version &clientVersion,
                                            const Extensions &extensions)
{
    // This logic is the same for both Renderbuffers and TextureAttachment.
    return extensions.colorBufferFloatRgbaCHROMIUM ||  // ES2
           extensions.colorBufferFloatEXT;             // ES3
}

static bool Float32BlendableSupport(const Version &clientVersion, const Extensions &extensions)
{
    // EXT_float_blend may be exposed on ES2 client contexts. Ensure that RGBA32F is renderable.
    return (extensions.colorBufferFloatRgbaCHROMIUM || extensions.colorBufferFloatEXT) &&
           extensions.floatBlendEXT;
}

template <ExtensionBool bool1>
static bool ETC2EACSupport(const Version &clientVersion, const Extensions &extensions)
{
    if (extensions.compressedTextureEtcANGLE)
    {
        return true;
    }

    // ETC2/EAC formats are always available in ES 3.0+ but require an extension (checked above)
    // in WebGL. If that extension is not available, hide these formats from WebGL contexts.
    return !extensions.webglCompatibilityANGLE &&
           (clientVersion >= Version(3, 0) || extensions.*bool1);
}

InternalFormat::InternalFormat()
    : internalFormat(GL_NONE),
      sized(false),
      sizedInternalFormat(GL_NONE),
      redBits(0),
      greenBits(0),
      blueBits(0),
      luminanceBits(0),
      alphaBits(0),
      sharedBits(0),
      depthBits(0),
      stencilBits(0),
      pixelBytes(0),
      componentCount(0),
      compressed(false),
      compressedBlockWidth(0),
      compressedBlockHeight(0),
      compressedBlockDepth(0),
      paletted(false),
      paletteBits(0),
      format(GL_NONE),
      type(GL_NONE),
      componentType(GL_NONE),
      colorEncoding(GL_NONE),
      textureSupport(NeverSupported),
      filterSupport(NeverSupported),
      textureAttachmentSupport(NeverSupported),
      renderbufferSupport(NeverSupported),
      blendSupport(NeverSupported)
{}

InternalFormat::InternalFormat(const InternalFormat &other) = default;

InternalFormat &InternalFormat::operator=(const InternalFormat &other) = default;

bool InternalFormat::isLUMA() const
{
    return ((redBits + greenBits + blueBits + depthBits + stencilBits) == 0 &&
            (luminanceBits + alphaBits) > 0);
}

GLenum InternalFormat::getReadPixelsFormat(const Extensions &extensions) const
{
    switch (format)
    {
        case GL_BGRA_EXT:
            // BGRA textures may be enabled but calling glReadPixels with BGRA is disallowed without
            // GL_EXT_texture_format_BGRA8888.  Read as RGBA instead.
            if (!extensions.readFormatBgraEXT)
            {
                return GL_RGBA;
            }
            return GL_BGRA_EXT;

        default:
            return format;
    }
}

GLenum InternalFormat::getReadPixelsType(const Version &version) const
{
    switch (type)
    {
        case GL_HALF_FLOAT:
        case GL_HALF_FLOAT_OES:
            if (version < Version(3, 0))
            {
                // The internal format may have a type of GL_HALF_FLOAT but when exposing this type
                // as the IMPLEMENTATION_READ_TYPE, only HALF_FLOAT_OES is allowed by
                // OES_texture_half_float.  HALF_FLOAT becomes core in ES3 and is acceptable to use
                // as an IMPLEMENTATION_READ_TYPE.
                return GL_HALF_FLOAT_OES;
            }
            return GL_HALF_FLOAT;

        default:
            return type;
    }
}

bool InternalFormat::supportSubImage() const
{
    return !CompressedFormatRequiresWholeImage(internalFormat);
}

bool InternalFormat::isRequiredRenderbufferFormat(const Version &version) const
{
    // GLES 3.0.5 section 4.4.2.2:
    // "Implementations are required to support the same internal formats for renderbuffers as the
    // required formats for textures enumerated in section 3.8.3.1, with the exception of the color
    // formats labelled "texture-only"."
    if (!sized || compressed)
    {
        return false;
    }

    // Luma formats.
    if (isLUMA())
    {
        return false;
    }

    // Depth/stencil formats.
    if (depthBits > 0 || stencilBits > 0)
    {
        // GLES 2.0.25 table 4.5.
        // GLES 3.0.5 section 3.8.3.1.
        // GLES 3.1 table 8.14.

        // Required formats in all versions.
        switch (internalFormat)
        {
            case GL_DEPTH_COMPONENT16:
            case GL_STENCIL_INDEX8:
                // Note that STENCIL_INDEX8 is not mentioned in GLES 3.0.5 section 3.8.3.1, but it
                // is in section 4.4.2.2.
                return true;
            default:
                break;
        }
        if (version.major < 3)
        {
            return false;
        }
        // Required formats in GLES 3.0 and up.
        switch (internalFormat)
        {
            case GL_DEPTH_COMPONENT32F:
            case GL_DEPTH_COMPONENT24:
            case GL_DEPTH32F_STENCIL8:
            case GL_DEPTH24_STENCIL8:
                return true;
            default:
                return false;
        }
    }

    // RGBA formats.
    // GLES 2.0.25 table 4.5.
    // GLES 3.0.5 section 3.8.3.1.
    // GLES 3.1 table 8.13.

    // Required formats in all versions.
    switch (internalFormat)
    {
        case GL_RGBA4:
        case GL_RGB5_A1:
        case GL_RGB565:
            return true;
        default:
            break;
    }
    if (version.major < 3)
    {
        return false;
    }

    if (format == GL_BGRA_EXT)
    {
        return false;
    }

    switch (componentType)
    {
        case GL_SIGNED_NORMALIZED:
        case GL_FLOAT:
            return false;
        case GL_UNSIGNED_INT:
        case GL_INT:
            // Integer RGB formats are not required renderbuffer formats.
            if (alphaBits == 0 && blueBits != 0)
            {
                return false;
            }
            // All integer R and RG formats are required.
            // Integer RGBA formats including RGB10_A2_UI are required.
            return true;
        case GL_UNSIGNED_NORMALIZED:
            if (internalFormat == GL_SRGB8)
            {
                return false;
            }
            return true;
        default:
            UNREACHABLE();
            return false;
    }
}

bool InternalFormat::isInt() const
{
    return componentType == GL_INT || componentType == GL_UNSIGNED_INT;
}

bool InternalFormat::isDepthOrStencil() const
{
    return depthBits != 0 || stencilBits != 0;
}

Format::Format(GLenum internalFormat) : Format(GetSizedInternalFormatInfo(internalFormat)) {}

Format::Format(const InternalFormat &internalFormat) : info(&internalFormat) {}

Format::Format(GLenum internalFormat, GLenum type)
    : info(&GetInternalFormatInfo(internalFormat, type))
{}

Format::Format(const Format &other)            = default;
Format &Format::operator=(const Format &other) = default;

bool Format::valid() const
{
    return info->internalFormat != GL_NONE;
}

// static
bool Format::SameSized(const Format &a, const Format &b)
{
    return a.info->sizedInternalFormat == b.info->sizedInternalFormat;
}

static GLenum EquivalentBlitInternalFormat(GLenum internalformat)
{
    // BlitFramebuffer works if the color channels are identically
    // sized, even if there is a swizzle (for example, blitting from a
    // multisampled RGBA8 renderbuffer to a BGRA8 texture). This could
    // be expanded and/or autogenerated if that is found necessary.
    if (internalformat == GL_BGRA8_EXT)
    {
        return GL_RGBA8;
    }

    // GL_ANGLE_rgbx_internal_format: Treat RGBX8 as RGB8, since the X channel is ignored.
    if (internalformat == GL_RGBX8_ANGLE)
    {
        return GL_RGB8;
    }

    // Treat ANGLE's BGRX8 as RGB8 since it's swizzled and the X channel is ignored.
    if (internalformat == GL_BGRX8_ANGLEX)
    {
        return GL_RGB8;
    }

    return internalformat;
}

// static
bool Format::EquivalentForBlit(const Format &a, const Format &b)
{
    return (EquivalentBlitInternalFormat(a.info->sizedInternalFormat) ==
            EquivalentBlitInternalFormat(b.info->sizedInternalFormat));
}

// static
Format Format::Invalid()
{
    static Format invalid(GL_NONE, GL_NONE);
    return invalid;
}

std::ostream &operator<<(std::ostream &os, const Format &fmt)
{
    // TODO(ynovikov): return string representation when available
    return FmtHex(os, fmt.info->sizedInternalFormat);
}

bool InternalFormat::operator==(const InternalFormat &other) const
{
    // We assume all internal formats are unique if they have the same internal format and type
    return internalFormat == other.internalFormat && type == other.type;
}

bool InternalFormat::operator!=(const InternalFormat &other) const
{
    return !(*this == other);
}

void InsertFormatInfo(InternalFormatInfoMap *map, const InternalFormat &formatInfo)
{
    ASSERT(!formatInfo.sized || (*map).count(formatInfo.internalFormat) == 0);
    ASSERT((*map)[formatInfo.internalFormat].count(formatInfo.type) == 0);
    (*map)[formatInfo.internalFormat][formatInfo.type] = formatInfo;
}

// YuvFormatInfo implementation
YuvFormatInfo::YuvFormatInfo(GLenum internalFormat, const Extents &yPlaneExtent)
{
    ASSERT(gl::IsYuvFormat(internalFormat));
    ASSERT((gl::GetPlaneCount(internalFormat) > 0) && (gl::GetPlaneCount(internalFormat) <= 3));

    glInternalFormat = internalFormat;
    planeCount       = gl::GetPlaneCount(internalFormat);

    // Chroma planes of a YUV format can be subsampled
    int horizontalSubsampleFactor = 0;
    int verticalSubsampleFactor   = 0;
    gl::GetSubSampleFactor(internalFormat, &horizontalSubsampleFactor, &verticalSubsampleFactor);

    // Compute plane Bpp
    planeBpp[0] = gl::GetYPlaneBpp(internalFormat);
    planeBpp[1] = gl::GetChromaPlaneBpp(internalFormat);
    planeBpp[2] = (planeCount > 2) ? planeBpp[1] : 0;

    // Compute plane extent
    planeExtent[0] = yPlaneExtent;
    planeExtent[1] = {(yPlaneExtent.width / horizontalSubsampleFactor),
                      (yPlaneExtent.height / verticalSubsampleFactor), yPlaneExtent.depth};
    planeExtent[2] = (planeCount > 2) ? planeExtent[1] : Extents();

    // Compute plane pitch
    planePitch[0] = planeExtent[0].width * planeBpp[0];
    planePitch[1] = planeExtent[1].width * planeBpp[1];
    planePitch[2] = planeExtent[2].width * planeBpp[2];

    // Compute plane size
    planeSize[0] = planePitch[0] * planeExtent[0].height;
    planeSize[1] = planePitch[1] * planeExtent[1].height;
    planeSize[2] = planePitch[2] * planeExtent[2].height;

    // Compute plane offset
    planeOffset[0] = 0;
    planeOffset[1] = planeSize[0];
    planeOffset[2] = planeSize[0] + planeSize[1];
}

// YUV format related helpers
bool IsYuvFormat(GLenum format)
{
    switch (format)
    {
        case GL_G8_B8R8_2PLANE_420_UNORM_ANGLE:
        case GL_G8_B8_R8_3PLANE_420_UNORM_ANGLE:
        case GL_G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G10X6_B10X6_R10X6_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4R12X4_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4_R12X4_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16R16_2PLANE_420_UNORM_ANGLE:
        case GL_G16_B16_R16_3PLANE_420_UNORM_ANGLE:
            return true;
        default:
            return false;
    }
}

uint32_t GetPlaneCount(GLenum format)
{
    switch (format)
    {
        case GL_G8_B8R8_2PLANE_420_UNORM_ANGLE:
        case GL_G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4R12X4_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16R16_2PLANE_420_UNORM_ANGLE:
            return 2;
        case GL_G8_B8_R8_3PLANE_420_UNORM_ANGLE:
        case GL_G10X6_B10X6_R10X6_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4_R12X4_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16_R16_3PLANE_420_UNORM_ANGLE:
            return 3;
        default:
            UNREACHABLE();
            return 0;
    }
}

uint32_t GetYPlaneBpp(GLenum format)
{
    switch (format)
    {
        case GL_G8_B8R8_2PLANE_420_UNORM_ANGLE:
        case GL_G8_B8_R8_3PLANE_420_UNORM_ANGLE:
            return 1;
        case GL_G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G10X6_B10X6_R10X6_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4R12X4_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4_R12X4_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16R16_2PLANE_420_UNORM_ANGLE:
        case GL_G16_B16_R16_3PLANE_420_UNORM_ANGLE:
            return 2;
        default:
            UNREACHABLE();
            return 0;
    }
}

uint32_t GetChromaPlaneBpp(GLenum format)
{
    // 2 plane 420 YUV formats have CbCr channels interleaved.
    // 3 plane 420 YUV formats have separate Cb and Cr planes.
    switch (format)
    {
        case GL_G8_B8_R8_3PLANE_420_UNORM_ANGLE:
            return 1;
        case GL_G8_B8R8_2PLANE_420_UNORM_ANGLE:
        case GL_G10X6_B10X6_R10X6_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4_R12X4_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16_R16_3PLANE_420_UNORM_ANGLE:
            return 2;
        case GL_G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4R12X4_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16R16_2PLANE_420_UNORM_ANGLE:
            return 4;
        default:
            UNREACHABLE();
            return 0;
    }
}

void GetSubSampleFactor(GLenum format, int *horizontalSubsampleFactor, int *verticalSubsampleFactor)
{
    ASSERT(horizontalSubsampleFactor && verticalSubsampleFactor);

    switch (format)
    {
        case GL_G8_B8R8_2PLANE_420_UNORM_ANGLE:
        case GL_G8_B8_R8_3PLANE_420_UNORM_ANGLE:
        case GL_G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G10X6_B10X6_R10X6_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4R12X4_2PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G12X4_B12X4_R12X4_3PLANE_420_UNORM_3PACK16_ANGLE:
        case GL_G16_B16R16_2PLANE_420_UNORM_ANGLE:
        case GL_G16_B16_R16_3PLANE_420_UNORM_ANGLE:
            *horizontalSubsampleFactor = 2;
            *verticalSubsampleFactor   = 2;
            break;
        default:
            UNREACHABLE();
            break;
    }
}

struct FormatBits
{
    constexpr GLuint pixelBytes() const
    {
        return (red + green + blue + alpha + shared + unused) / 8;
    }
    constexpr GLuint componentCount() const
    {
        return ((red > 0) ? 1 : 0) + ((green > 0) ? 1 : 0) + ((blue > 0) ? 1 : 0) +
               ((alpha > 0) ? 1 : 0);
    }
    constexpr bool valid() const
    {
        return ((red + green + blue + alpha + shared + unused) % 8) == 0;
    }

    GLuint red;
    GLuint green;
    GLuint blue;
    GLuint alpha;
    GLuint unused;
    GLuint shared;
};

template <GLuint red, GLuint green, GLuint blue, GLuint alpha, GLuint unused, GLuint shared>
constexpr FormatBits FB()
{
    constexpr FormatBits formatBits = {red, green, blue, alpha, unused, shared};
    static_assert(formatBits.valid(), "Invalid FormatBits");
    return formatBits;
}

void AddRGBAXFormat(InternalFormatInfoMap *map,
                    GLenum internalFormat,
                    bool sized,
                    const FormatBits &formatBits,
                    GLenum format,
                    GLenum type,
                    GLenum componentType,
                    bool srgb,
                    InternalFormat::SupportCheckFunction textureSupport,
                    InternalFormat::SupportCheckFunction filterSupport,
                    InternalFormat::SupportCheckFunction textureAttachmentSupport,
                    InternalFormat::SupportCheckFunction renderbufferSupport,
                    InternalFormat::SupportCheckFunction blendSupport)
{
    ASSERT(formatBits.valid());

    InternalFormat formatInfo;
    formatInfo.internalFormat = internalFormat;
    formatInfo.sized          = sized;
    formatInfo.sizedInternalFormat =
        sized ? internalFormat : GetSizedFormatInternal(internalFormat, type);
    formatInfo.redBits                  = formatBits.red;
    formatInfo.greenBits                = formatBits.green;
    formatInfo.blueBits                 = formatBits.blue;
    formatInfo.alphaBits                = formatBits.alpha;
    formatInfo.sharedBits               = formatBits.shared;
    formatInfo.pixelBytes               = formatBits.pixelBytes();
    formatInfo.componentCount           = formatBits.componentCount();
    formatInfo.format                   = format;
    formatInfo.type                     = type;
    formatInfo.componentType            = componentType;
    formatInfo.colorEncoding            = (srgb ? GL_SRGB : GL_LINEAR);
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

void AddRGBAFormat(InternalFormatInfoMap *map,
                   GLenum internalFormat,
                   bool sized,
                   GLuint red,
                   GLuint green,
                   GLuint blue,
                   GLuint alpha,
                   GLuint shared,
                   GLenum format,
                   GLenum type,
                   GLenum componentType,
                   bool srgb,
                   InternalFormat::SupportCheckFunction textureSupport,
                   InternalFormat::SupportCheckFunction filterSupport,
                   InternalFormat::SupportCheckFunction textureAttachmentSupport,
                   InternalFormat::SupportCheckFunction renderbufferSupport,
                   InternalFormat::SupportCheckFunction blendSupport)
{
    return AddRGBAXFormat(map, internalFormat, sized, {red, green, blue, alpha, 0, shared}, format,
                          type, componentType, srgb, textureSupport, filterSupport,
                          textureAttachmentSupport, renderbufferSupport, blendSupport);
}

static void AddLUMAFormat(InternalFormatInfoMap *map,
                          GLenum internalFormat,
                          bool sized,
                          GLuint luminance,
                          GLuint alpha,
                          GLenum format,
                          GLenum type,
                          GLenum componentType,
                          InternalFormat::SupportCheckFunction textureSupport,
                          InternalFormat::SupportCheckFunction filterSupport,
                          InternalFormat::SupportCheckFunction textureAttachmentSupport,
                          InternalFormat::SupportCheckFunction renderbufferSupport,
                          InternalFormat::SupportCheckFunction blendSupport)
{
    InternalFormat formatInfo;
    formatInfo.internalFormat = internalFormat;
    formatInfo.sized          = sized;
    formatInfo.sizedInternalFormat =
        sized ? internalFormat : GetSizedFormatInternal(internalFormat, type);
    formatInfo.luminanceBits            = luminance;
    formatInfo.alphaBits                = alpha;
    formatInfo.pixelBytes               = (luminance + alpha) / 8;
    formatInfo.componentCount           = ((luminance > 0) ? 1 : 0) + ((alpha > 0) ? 1 : 0);
    formatInfo.format                   = format;
    formatInfo.type                     = type;
    formatInfo.componentType            = componentType;
    formatInfo.colorEncoding            = GL_LINEAR;
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

void AddDepthStencilFormat(InternalFormatInfoMap *map,
                           GLenum internalFormat,
                           bool sized,
                           GLuint depthBits,
                           GLuint stencilBits,
                           GLuint unusedBits,
                           GLenum format,
                           GLenum type,
                           GLenum componentType,
                           InternalFormat::SupportCheckFunction textureSupport,
                           InternalFormat::SupportCheckFunction filterSupport,
                           InternalFormat::SupportCheckFunction textureAttachmentSupport,
                           InternalFormat::SupportCheckFunction renderbufferSupport,
                           InternalFormat::SupportCheckFunction blendSupport)
{
    InternalFormat formatInfo;
    formatInfo.internalFormat = internalFormat;
    formatInfo.sized          = sized;
    formatInfo.sizedInternalFormat =
        sized ? internalFormat : GetSizedFormatInternal(internalFormat, type);
    formatInfo.depthBits                = depthBits;
    formatInfo.stencilBits              = stencilBits;
    formatInfo.pixelBytes               = (depthBits + stencilBits + unusedBits) / 8;
    formatInfo.componentCount           = ((depthBits > 0) ? 1 : 0) + ((stencilBits > 0) ? 1 : 0);
    formatInfo.format                   = format;
    formatInfo.type                     = type;
    formatInfo.componentType            = componentType;
    formatInfo.colorEncoding            = GL_LINEAR;
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

void AddCompressedFormat(InternalFormatInfoMap *map,
                         GLenum internalFormat,
                         GLuint compressedBlockWidth,
                         GLuint compressedBlockHeight,
                         GLuint compressedBlockDepth,
                         GLuint compressedBlockSize,
                         GLuint componentCount,
                         bool srgb,
                         InternalFormat::SupportCheckFunction textureSupport,
                         InternalFormat::SupportCheckFunction filterSupport,
                         InternalFormat::SupportCheckFunction textureAttachmentSupport,
                         InternalFormat::SupportCheckFunction renderbufferSupport,
                         InternalFormat::SupportCheckFunction blendSupport)
{
    InternalFormat formatInfo;
    formatInfo.internalFormat           = internalFormat;
    formatInfo.sized                    = true;
    formatInfo.sizedInternalFormat      = internalFormat;
    formatInfo.compressedBlockWidth     = compressedBlockWidth;
    formatInfo.compressedBlockHeight    = compressedBlockHeight;
    formatInfo.compressedBlockDepth     = compressedBlockDepth;
    formatInfo.pixelBytes               = compressedBlockSize / 8;
    formatInfo.componentCount           = componentCount;
    formatInfo.format                   = internalFormat;
    formatInfo.type                     = GL_UNSIGNED_BYTE;
    formatInfo.componentType            = GL_UNSIGNED_NORMALIZED;
    formatInfo.colorEncoding            = (srgb ? GL_SRGB : GL_LINEAR);
    formatInfo.compressed               = true;
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

void AddPalettedFormat(InternalFormatInfoMap *map,
                       GLenum internalFormat,
                       GLuint paletteBits,
                       GLuint pixelBytes,
                       GLenum format,
                       GLuint componentCount,
                       InternalFormat::SupportCheckFunction textureSupport,
                       InternalFormat::SupportCheckFunction filterSupport,
                       InternalFormat::SupportCheckFunction textureAttachmentSupport,
                       InternalFormat::SupportCheckFunction renderbufferSupport,
                       InternalFormat::SupportCheckFunction blendSupport)
{
    InternalFormat formatInfo;
    formatInfo.internalFormat           = internalFormat;
    formatInfo.sized                    = true;
    formatInfo.sizedInternalFormat      = internalFormat;
    formatInfo.paletteBits              = paletteBits;
    formatInfo.pixelBytes               = pixelBytes;
    formatInfo.componentCount           = componentCount;
    formatInfo.format                   = format;
    formatInfo.type                     = GL_UNSIGNED_BYTE;
    formatInfo.componentType            = GL_UNSIGNED_NORMALIZED;
    formatInfo.colorEncoding            = GL_LINEAR;
    formatInfo.paletted                 = true;
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

void AddYUVFormat(InternalFormatInfoMap *map,
                  GLenum internalFormat,
                  bool sized,
                  GLuint cr,
                  GLuint y,
                  GLuint cb,
                  GLuint alpha,
                  GLuint shared,
                  GLenum format,
                  GLenum type,
                  GLenum componentType,
                  bool srgb,
                  InternalFormat::SupportCheckFunction textureSupport,
                  InternalFormat::SupportCheckFunction filterSupport,
                  InternalFormat::SupportCheckFunction textureAttachmentSupport,
                  InternalFormat::SupportCheckFunction renderbufferSupport,
                  InternalFormat::SupportCheckFunction blendSupport)
{
    ASSERT(sized);

    InternalFormat formatInfo;
    formatInfo.internalFormat      = internalFormat;
    formatInfo.sized               = sized;
    formatInfo.sizedInternalFormat = internalFormat;
    formatInfo.redBits             = cr;
    formatInfo.greenBits           = y;
    formatInfo.blueBits            = cb;
    formatInfo.alphaBits           = alpha;
    formatInfo.sharedBits          = shared;
    formatInfo.pixelBytes          = (cr + y + cb + alpha + shared) / 8;
    formatInfo.componentCount =
        ((cr > 0) ? 1 : 0) + ((y > 0) ? 1 : 0) + ((cb > 0) ? 1 : 0) + ((alpha > 0) ? 1 : 0);
    formatInfo.format                   = format;
    formatInfo.type                     = type;
    formatInfo.componentType            = componentType;
    formatInfo.colorEncoding            = (srgb ? GL_SRGB : GL_LINEAR);
    formatInfo.textureSupport           = textureSupport;
    formatInfo.filterSupport            = filterSupport;
    formatInfo.textureAttachmentSupport = textureAttachmentSupport;
    formatInfo.renderbufferSupport      = renderbufferSupport;
    formatInfo.blendSupport             = blendSupport;

    InsertFormatInfo(map, formatInfo);
}

// Notes:
// 1. "Texture supported" includes all the means by which texture can be created, however,
//    GL_EXT_texture_storage in ES2 is a special case, when only glTexStorage* is allowed.
//    The assumption is that ES2 validation will not check textureSupport for sized formats.
//
// 2. Sized half float types are a combination of GL_HALF_FLOAT and GL_HALF_FLOAT_OES support,
//    due to a limitation that only one type for sized formats is allowed.
//
// TODO(ynovikov): http://anglebug.com/2846 Verify support fields of BGRA, depth, stencil
// and compressed formats. Perform texturable check as part of filterable and attachment checks.
static InternalFormatInfoMap BuildInternalFormatInfoMap()
{
    InternalFormatInfoMap map;

    // From ES 3.0.1 spec, table 3.12
    map[GL_NONE][GL_NONE] = InternalFormat();

    // clang-format off

    //                 | Internal format     |sized| R | G | B | A |S | Format         | Type                             | Component type        | SRGB | Texture supported                                | Filterable     | Texture attachment                               | Renderbuffer                                   | Blend
    AddRGBAFormat(&map, GL_R8,                true,  8,  0,  0,  0, 0, GL_RED,          GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, SizedRGSupport,                                       AlwaysSupported, SizedRGSupport,                                          RequireESOrExt<3, 0, &Extensions::textureRgEXT>, RequireESOrExt<3, 0, &Extensions::textureRgEXT>);
    AddRGBAFormat(&map, GL_R8_SNORM,          true,  8,  0,  0,  0, 0, GL_RED,          GL_BYTE,                           GL_SIGNED_NORMALIZED,   false, RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RG8,               true,  8,  8,  0,  0, 0, GL_RG,           GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, SizedRGSupport,                                       AlwaysSupported, SizedRGSupport,                                          RequireESOrExt<3, 0, &Extensions::textureRgEXT>, RequireESOrExt<3, 0, &Extensions::textureRgEXT>);
    AddRGBAFormat(&map, GL_RG8_SNORM,         true,  8,  8,  0,  0, 0, GL_RG,           GL_BYTE,                           GL_SIGNED_NORMALIZED,   false, RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB8,              true,  8,  8,  8,  0, 0, GL_RGB,          GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, AlwaysSupported, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, RequireESOrExt<3, 0, &Extensions::rgb8Rgba8OES>,    RequireESOrExt<3, 0, &Extensions::rgb8Rgba8OES>);
    AddRGBAFormat(&map, GL_RGB8_SNORM,        true,  8,  8,  8,  0, 0, GL_RGB,          GL_BYTE,                           GL_SIGNED_NORMALIZED,   false, RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB565,            true,  5,  6,  5,  0, 0, GL_RGB,          GL_UNSIGNED_SHORT_5_6_5,           GL_UNSIGNED_NORMALIZED, false, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, AlwaysSupported, RequireESOrExt<3, 0, &Extensions::textureStorageEXT&gt;, RequireES<2, 0>,                                    RequireES<2, 0>);
    AddRGBAFormat(&map, GL_RGBA4,             true,  4,  4,  4,  4, 0, GL_RGBA,         GL_UNSIGNED_SHORT_4_4_4_4,         GL_UNSIGNED_NORMALIZED, false, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, AlwaysSupported, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, RequireES<2, 0>,                                    RequireES<2, 0>);
    AddRGBAFormat(&map, GL_RGB5_A1,           true,  5,  5,  5,  1, 0, GL_RGBA,         GL_UNSIGNED_SHORT_5_5_5_1,         GL_UNSIGNED_NORMALIZED, false, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, AlwaysSupported, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, RequireES<2, 0>,                                    RequireES<2, 0>);
    AddRGBAFormat(&map, GL_RGBA8,             true,  8,  8,  8,  8, 0, GL_RGBA,         GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, AlwaysSupported, RequireESOrExt<3, 0, &Extensions::textureStorageEXT>, RequireESOrExt<3, 0, &Extensions::rgb8Rgba8OES>,    RequireESOrExt<3, 0, &Extensions::rgb8Rgba8OES>);
    AddRGBAFormat(&map, GL_RGBA8_SNORM,       true,  8,  8,  8,  8, 0, GL_RGBA,         GL_BYTE,                           GL_SIGNED_NORMALIZED,   false, RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB10_A2UI,        true, 10, 10, 10,  2, 0, GL_RGBA_INTEGER, GL_UNSIGNED_INT_2_10_10_10_REV,    GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_SRGB8,             true,  8,  8,  8,  0, 0, GL_RGB,          GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, true,  RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_SRGB8_ALPHA8,      true,  8,  8,  8,  8, 0, GL_RGBA,         GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, true,  RequireESOrExt<3, 0, &Extensions::sRGBEXT>,           AlwaysSupported, RequireES<3, 0>,                                         RequireESOrExt<3, 0, &Extensions::sRGBEXT>,      RequireESOrExt<3, 0, &Extensions::sRGBEXT>);
    AddRGBAFormat(&map, GL_R11F_G11F_B10F,    true, 11, 11, 10,  0, 0, GL_RGB,          GL_UNSIGNED_INT_10F_11F_11F_REV,   GL_FLOAT,               false, RequireES<3, 0>,                                      AlwaysSupported, RequireExt<&Extensions::colorBufferFloatEXT>,            RequireExt<&Extensions::colorBufferFloatEXT>,    RequireExt<&Extensions::colorBufferFloatEXT>);
    AddRGBAFormat(&map, GL_RGB9_E5,           true,  9,  9,  9,  0, 5, GL_RGB,          GL_UNSIGNED_INT_5_9_9_9_REV,       GL_FLOAT,               false, RequireES<3, 0>,                                      AlwaysSupported, NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_R8I,               true,  8,  0,  0,  0, 0, GL_RED_INTEGER,  GL_BYTE,                           GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_R8UI,              true,  8,  0,  0,  0, 0, GL_RED_INTEGER,  GL_UNSIGNED_BYTE,                  GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_R16I,              true, 16,  0,  0,  0, 0, GL_RED_INTEGER,  GL_SHORT,                          GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_R16UI,             true, 16,  0,  0,  0, 0, GL_RED_INTEGER,  GL_UNSIGNED_SHORT,                 GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_R32I,              true, 32,  0,  0,  0, 0, GL_RED_INTEGER,  GL_INT,                            GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_R32UI,             true, 32,  0,  0,  0, 0, GL_RED_INTEGER,  GL_UNSIGNED_INT,                   GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG8I,              true,  8,  8,  0,  0, 0, GL_RG_INTEGER,   GL_BYTE,                           GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG8UI,             true,  8,  8,  0,  0, 0, GL_RG_INTEGER,   GL_UNSIGNED_BYTE,                  GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG16I,             true, 16, 16,  0,  0, 0, GL_RG_INTEGER,   GL_SHORT,                          GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG16UI,            true, 16, 16,  0,  0, 0, GL_RG_INTEGER,   GL_UNSIGNED_SHORT,                 GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG32I,             true, 32, 32,  0,  0, 0, GL_RG_INTEGER,   GL_INT,                            GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RG32UI,            true, 32, 32,  0,  0, 0, GL_RG_INTEGER,   GL_UNSIGNED_INT,                   GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGB8I,             true,  8,  8,  8,  0, 0, GL_RGB_INTEGER,  GL_BYTE,                           GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB8UI,            true,  8,  8,  8,  0, 0, GL_RGB_INTEGER,  GL_UNSIGNED_BYTE,                  GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB16I,            true, 16, 16, 16,  0, 0, GL_RGB_INTEGER,  GL_SHORT,                          GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB16UI,           true, 16, 16, 16,  0, 0, GL_RGB_INTEGER,  GL_UNSIGNED_SHORT,                 GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB32I,            true, 32, 32, 32,  0, 0, GL_RGB_INTEGER,  GL_INT,                            GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGB32UI,           true, 32, 32, 32,  0, 0, GL_RGB_INTEGER,  GL_UNSIGNED_INT,                   GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  NeverSupported,                                          NeverSupported,                                  NeverSupported);
    AddRGBAFormat(&map, GL_RGBA8I,            true,  8,  8,  8,  8, 0, GL_RGBA_INTEGER, GL_BYTE,                           GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGBA8UI,           true,  8,  8,  8,  8, 0, GL_RGBA_INTEGER, GL_UNSIGNED_BYTE,                  GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGBA16I,           true, 16, 16, 16, 16, 0, GL_RGBA_INTEGER, GL_SHORT,                          GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGBA16UI,          true, 16, 16, 16, 16, 0, GL_RGBA_INTEGER, GL_UNSIGNED_SHORT,                 GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGBA32I,           true, 32, 32, 32, 32, 0, GL_RGBA_INTEGER, GL_INT,                            GL_INT,                 false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);
    AddRGBAFormat(&map, GL_RGBA32UI,          true, 32, 32, 32, 32, 0, GL_RGBA_INTEGER, GL_UNSIGNED_INT,                   GL_UNSIGNED_INT,        false, RequireES<3, 0>,                                      NeverSupported,  RequireES<3, 0>,                                         RequireES<3, 0>,                                 NeverSupported);

    AddRGBAFormat(&map, GL_BGRA8_EXT,         true,  8,  8,  8,  8, 0, GL_BGRA_EXT,     GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    AlwaysSupported, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    RequireExt<&Extensions::textureFormatBGRA8888EXT>;, RequireExt<&Extensions::textureFormatBGRA8888EXT>);
    AddRGBAFormat(&map, GL_BGRA4_ANGLEX,      true,  4,  4,  4,  4, 0, GL_BGRA_EXT,     GL_UNSIGNED_SHORT_4_4_4_4_REV_EXT, GL_UNSIGNED_NORMALIZED, false, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    AlwaysSupported, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    RequireExt<&Extensions::textureFormatBGRA8888EXT>, RequireExt<&Extensions::textureFormatBGRA8888EXT>);
    AddRGBAFormat(&map, GL_BGR5_A1_ANGLEX,    true,  5,  5,  5,  1, 0, GL_BGRA_EXT,     GL_UNSIGNED_SHORT_1_5_5_5_REV_EXT, GL_UNSIGNED_NORMALIZED, false, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    AlwaysSupported, RequireExt<&Extensions::textureFormatBGRA8888EXT>,    RequireExt<&Extensions::textureFormatBGRA8888EXT>, RequireExt<&Extensions::textureFormatBGRA8888EXT>);

    // Special format that is used for D3D textures that are used within ANGLE via the
    // EGL_ANGLE_d3d_texture_client_buffer extension. We don't allow uploading texture images with
    // this format, but textures in this format can be created from D3D textures, and filtering them
    // and rendering to them is allowed.
    AddRGBAFormat(&map, GL_BGRA8_SRGB_ANGLEX, true,  8,  8,  8,  8, 0, GL_BGRA_EXT,     GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, true,  NeverSupported,                                    AlwaysSupported, AlwaysSupported,                                   AlwaysSupported,                               AlwaysSupported);

    // Special format which is not really supported, so always false for all supports.
    AddRGBAFormat(&map, GL_BGR565_ANGLEX,     true,  5,  6,  5,  0, 0, GL_BGRA_EXT,     GL_UNSIGNED_SHORT_5_6_5,           GL_UNSIGNED_NORMALIZED, false, NeverSupported,                                    NeverSupported,  NeverSupported,                                    NeverSupported,                                NeverSupported);
    AddRGBAFormat(&map, GL_BGR10_A2_ANGLEX,   true, 10, 10, 10,  2, 0, GL_BGRA_EXT,     GL_UNSIGNED_INT_2_10_10_10_REV,    GL_UNSIGNED_NORMALIZED, false, NeverSupported,                                    NeverSupported,  NeverSupported,                                    NeverSupported,                                NeverSupported);

    // Special format to emulate RGB8 with RGBA8 within ANGLE.
    AddRGBAFormat(&map, GL_RGBX8_ANGLE,      true,   8,  8,  8,  0, 0, GL_RGB,          GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, AlwaysSupported,                                   AlwaysSupported, AlwaysSupported,                                   AlwaysSupported,                               NeverSupported);

    // Special format to emulate BGR8 with BGRA8 within ANGLE.
    AddRGBAFormat(&map, GL_BGRX8_ANGLEX,      true,  8,  8,  8,  0, 0, GL_BGRA_EXT,     GL_UNSIGNED_BYTE,                  GL_UNSIGNED_NORMALIZED, false, NeverSupported,                                    AlwaysSupported,  NeverSupported,                                    NeverSupported,                                NeverSupported);

    // This format is supported on ES 2.0 with two extensions, so keep it out-of-line to not widen the table above even more.
    //                 | Internal format     |sized| R | G | B | A |S | Format         | Type                             | Component type        | SRGB | Texture supported                                                                            | Filterable     | Texture attachment                               | Renderbuffer                                   | Blend
    AddRGBAFormat(&map, GL_RGB10_A2,          true, 10, 10, 10,  2, 0, GL_RGBA,         GL_UNSIGNED_INT_2_10_10_10_REV,    GL_UNSIGNED_NORMALIZED, false, RequireESOrExtAndExt<3, 0, &Extensions::textureStorageEXT, &Extensions::textureType2101010REVEXT>,  AlwaysSupported, RequireES<3, 0>,                                   RequireES<3, 0>,                                 RequireES<3, 0>);

    // Floating point formats
    //                 | Internal format |sized| R | G | B | A |S | Format | Type             | Component type | SRGB | Texture supported         | Filterable                                    | Texture attachment                          | Renderbuffer                            | Blend
    // It's not possible to have two entries per sized format.
    // E.g. for GL_RG16F, one with GL_HALF_FLOAT type and the other with GL_HALF_FLOAT_OES type.
    // So, GL_HALF_FLOAT type formats conditions are merged with GL_HALF_FLOAT_OES type conditions.
    AddRGBAFormat(&map, GL_R16F,          true, 16,  0,  0,  0, 0, GL_RED,  GL_HALF_FLOAT,     GL_FLOAT,        false, SizedHalfFloatRGSupport,    SizedHalfFloatFilterSupport,                    SizedHalfFloatRGTextureAttachmentSupport,     SizedHalfFloatRGRenderbufferSupport,       SizedHalfFloatRGRenderbufferSupport);
    AddRGBAFormat(&map, GL_RG16F,         true, 16, 16,  0,  0, 0, GL_RG,   GL_HALF_FLOAT,     GL_FLOAT,        false, SizedHalfFloatRGSupport,    SizedHalfFloatFilterSupport,                    SizedHalfFloatRGTextureAttachmentSupport,     SizedHalfFloatRGRenderbufferSupport,       SizedHalfFloatRGRenderbufferSupport);
    AddRGBAFormat(&map, GL_RGB16F,        true, 16, 16, 16,  0, 0, GL_RGB,  GL_HALF_FLOAT,     GL_FLOAT,        false, SizedHalfFloatSupport,      SizedHalfFloatFilterSupport,                    SizedHalfFloatRGBTextureAttachmentSupport,    SizedHalfFloatRGBRenderbufferSupport,      SizedHalfFloatRGBRenderbufferSupport);
    AddRGBAFormat(&map, GL_RGBA16F,       true, 16, 16, 16, 16, 0, GL_RGBA, GL_HALF_FLOAT,     GL_FLOAT,        false, SizedHalfFloatSupport,      SizedHalfFloatFilterSupport,                    SizedHalfFloatRGBATextureAttachmentSupport,   SizedHalfFloatRGBARenderbufferSupport,     SizedHalfFloatRGBARenderbufferSupport);
    AddRGBAFormat(&map, GL_R32F,          true, 32,  0,  0,  0, 0, GL_RED,  GL_FLOAT,          GL_FLOAT,        false, SizedFloatRGSupport,        RequireExt<&Extensions::textureFloatLinearOES>, RequireExt<&Extensions::colorBufferFloatEXT>,    RequireExt<&Extensions::colorBufferFloatEXT>, Float32BlendableSupport);
    AddRGBAFormat(&map, GL_RG32F,         true, 32, 32,  0,  0, 0, GL_RG,   GL_FLOAT,          GL_FLOAT,        false, SizedFloatRGSupport,        RequireExt<&Extensions::textureFloatLinearOES>, RequireExt<&Extensions::colorBufferFloatEXT>,    RequireExt<&Extensions::colorBufferFloatEXT>, Float32BlendableSupport);
    AddRGBAFormat(&map, GL_RGB32F,        true, 32, 32, 32,  0, 0, GL_RGB,  GL_FLOAT,          GL_FLOAT,        false, SizedFloatRGBSupport,       RequireExt<&Extensions::textureFloatLinearOES>, RequireExt<&Extensions::colorBufferFloatRgbCHROMIUM>, NeverSupported,                            NeverSupported);
    AddRGBAFormat(&map, GL_RGBA32F,       true, 32, 32, 32, 32, 0, GL_RGBA, GL_FLOAT,          GL_FLOAT,        false, SizedFloatRGBASupport,      RequireExt<&Extensions::textureFloatLinearOES>, SizedFloatRGBARenderableSupport,              SizedFloatRGBARenderableSupport,           Float32BlendableSupport);

    // ANGLE Depth stencil formats
    //                         | Internal format         |sized| D |S | X | Format            | Type                             | Component type        | Texture supported                                                                            | Filterable                                                                             | Texture attachment                                                                           | Renderbuffer                                                                                              | Blend
    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT16,     true, 16, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_SHORT,                 GL_UNSIGNED_NORMALIZED, RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::depthTextureOES>,       RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::depthTextureOES>, RequireES<1, 0>,                                                                               RequireES<1, 0>,                                                                                             RequireES<1, 0>);
    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT24,     true, 24, 0,  8, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,                   GL_UNSIGNED_NORMALIZED, RequireES<3, 0>,                                                                               RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>,                                    RequireES<3, 0>,                                                                               RequireESOrExt<3, 0, &Extensions::depth24OES>,                                                               RequireESOrExt<3, 0, &Extensions::depth24OES>);
    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT32F,    true, 32, 0,  0, GL_DEPTH_COMPONENT, GL_FLOAT,                          GL_FLOAT,               RequireES<3, 0>,                                                                               RequireESOrExt<3, 0, &Extensions::depthTextureANGLE>,                                    RequireES<3, 0>,                                                                               RequireES<3, 0>,                                                                                             RequireES<3, 0>);
    AddDepthStencilFormat(&map, GL_DEPTH_COMPONENT32_OES, true, 32, 0,  0, GL_DEPTH_COMPONENT, GL_UNSIGNED_INT,                   GL_UNSIGNED_NORMALIZED, RequireExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES>,                 AlwaysSupported,                                                                         RequireExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES>,                 RequireExtOrExtOrExt<&Extensions::depthTextureANGLE, &Extensions::depthTextureOES, &Extensions::depth32OES>, RequireExtOrExtOrExt<&Extensions::depthTextureANGLE,&nbsp;&Extensions::depthTextureOES, &Extensions::depth32OES>);
    AddDepthStencilFormat(&map, GL_DEPTH24_STENCIL8,      true, 24, 8,  0, GL_DEPTH_STENCIL,   GL_UNSIGNED_INT_24_8,              GL_UNSIGNED_NORMALIZED, RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencilOES>, AlwaysSupported,                                                                         RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencilOES>, RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencilOES>,               RequireESOrExtOrExt<3, 0, &Extensions::depthTextureANGLE, &Extensions::packedDepthStencilOES>);
    AddDepthStencilFormat(&map, GL_DEPTH32F_STENCIL8,     true, 32, 8, 24, GL_DEPTH_STENCIL,   GL_FLOAT_32_UNSIGNED_INT_24_8_REV, GL_FLOAT,               RequireESOrExt<3, 0, &Extensions::depthBufferFloat2NV>,                                        AlwaysSupported,                                                                         RequireESOrExt<3, 0, &Extensions::depthBufferFloat2NV>,                                        RequireESOrExt<3, 0, &Extensions::depthBufferFloat2NV>,                                                      RequireESOrExt<3, 0, &Extensions::depthBufferFloat2NV>);
    // STENCIL_INDEX8 is special-cased, see around the bottom of the list.

    // Luminance alpha formats
    //                | Internal format           |sized| L | A | Format            | Type             | Component type        | Texture supported                                                           | Filterable                                     | Texture attachment | Renderbuffer | Blend
    AddLUMAFormat(&map, GL_ALPHA8_EXT,             true,  0,  8, GL_ALPHA,           GL_UNSIGNED_BYTE,  GL_UNSIGNED_NORMALIZED, RequireExt<&Extensions::textureStorageEXT>,                                      AlwaysSupported,                                 NeverSupported,      NeverSupported, NeverSupported);
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