Quelle  validationES2.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.
//

// validationES2.cpp: Validation functions for OpenGL ES 2.0 entry point parameters

#include "libANGLE/validationES2_autogen.h"

#include <cstdint>

#include "common/mathutil.h"
#include "common/string_utils.h"
#include "common/utilities.h"
#include "libANGLE/Context.h"
#include "libANGLE/ErrorStrings.h"
#include "libANGLE/Fence.h"
#include "libANGLE/Framebuffer.h"
#include "libANGLE/FramebufferAttachment.h"
#include "libANGLE/MemoryObject.h"
#include "libANGLE/Renderbuffer.h"
#include "libANGLE/Shader.h"
#include "libANGLE/Texture.h"
#include "libANGLE/Uniform.h"
#include "libANGLE/VertexArray.h"
#include "libANGLE/formatutils.h"
#include "libANGLE/validationES.h"
#include "libANGLE/validationES2.h"
#include "libANGLE/validationES3_autogen.h"

namespace gl
{
using namespace err;

namespace
{

bool IsPartialBlit(const Context *context,
                   const FramebufferAttachment *readBuffer,
                   const FramebufferAttachment *writeBuffer,
                   GLint srcX0,
                   GLint srcY0,
                   GLint srcX1,
                   GLint srcY1,
                   GLint dstX0,
                   GLint dstY0,
                   GLint dstX1,
                   GLint dstY1)
{
    const Extents &writeSize = writeBuffer->getSize();
    const Extents &readSize  = readBuffer->getSize();

    if (srcX0 != 0 || srcY0 != 0 || dstX0 != 0 || dstY0 != 0 || dstX1 != writeSize.width ||
        dstY1 != writeSize.height || srcX1 != readSize.width || srcY1 != readSize.height)
    {
        return true;
    }

    if (context->getState().isScissorTestEnabled())
    {
        const Rectangle &scissor = context->getState().getScissor();
        return scissor.x > 0 || scissor.y > 0 || scissor.width < writeSize.width ||
               scissor.height < writeSize.height;
    }

    return false;
}

bool IsValidCopyTextureSourceInternalFormatEnum(GLenum internalFormat)
{
    // Table 1.1 from the CHROMIUM_copy_texture spec
    switch (GetUnsizedFormat(internalFormat))
    {
        case GL_RED:
        case GL_ALPHA:
        case GL_LUMINANCE:
        case GL_LUMINANCE_ALPHA:
        case GL_RGB:
        case GL_RGBA:
        case GL_RGB8:
        case GL_RGBA8:
        case GL_BGRA_EXT:
        case GL_BGRA8_EXT:
            return true;

        default:
            return false;
    }
}

bool IsValidCopySubTextureSourceInternalFormat(GLenum internalFormat)
{
    return IsValidCopyTextureSourceInternalFormatEnum(internalFormat);
}

bool IsValidCopyTextureDestinationInternalFormatEnum(GLint internalFormat)
{
    // Table 1.0 from the CHROMIUM_copy_texture spec
    switch (internalFormat)
    {
        case GL_ALPHA:
        case GL_BGRA8_EXT:
        case GL_BGRA_EXT:
        case GL_LUMINANCE:
        case GL_LUMINANCE_ALPHA:
        case GL_R11F_G11F_B10F:
        case GL_R16F:
        case GL_R32F:
        case GL_R8:
        case GL_R8UI:
        case GL_RG16F:
        case GL_RG32F:
        case GL_RG8:
        case GL_RG8UI:
        case GL_RGB:
        case GL_RGB10_A2:
        case GL_RGB16F:
        case GL_RGB32F:
        case GL_RGB565:
        case GL_RGB5_A1:
        case GL_RGB8:
        case GL_RGB8UI:
        case GL_RGB9_E5:
        case GL_RGBA:
        case GL_RGBA16F:
        case GL_RGBA32F:
        case GL_RGBA4:
        case GL_RGBA8:
        case GL_RGBA8UI:
        case GL_RGBX8_ANGLE:
        case GL_SRGB8:
        case GL_SRGB8_ALPHA8:
        case GL_SRGB_ALPHA_EXT:
        case GL_SRGB_EXT:
            return true;

        default:
            return false;
    }
}

bool IsValidCopySubTextureDestionationInternalFormat(GLenum internalFormat)
{
    return IsValidCopyTextureDestinationInternalFormatEnum(internalFormat);
}

bool IsValidCopyTextureDestinationFormatType(const Context *context,
                                             angle::EntryPoint entryPoint,
                                             GLint internalFormat,
                                             GLenum type)
{
    if (!IsValidCopyTextureDestinationInternalFormatEnum(internalFormat))
    {
        context->validationErrorF(entryPoint, GL_INVALID_OPERATION, kInvalidInternalFormat,
                                  internalFormat);
        return false;
    }

    if (!ValidES3FormatCombination(GetUnsizedFormat(internalFormat), type, internalFormat))
    {
        context->validationError(entryPoint, GL_INVALID_OPERATION, kMismatchedTypeAndFormat);
        return false;
    }

    const InternalFormat &internalFormatInfo = GetInternalFormatInfo(internalFormat, type);
    if (!internalFormatInfo.textureSupport(context->getClientVersion(), context->getExtensions()))
    {
        context->validationErrorF(entryPoint, GL_INVALID_OPERATION, kInvalidInternalFormat,
                                  internalFormat);
        return false;
    }

    return true;
}

bool IsValidCopyTextureDestinationTargetEnum(const Context *context, TextureTarget target)
{
    switch (target)
    {
        case TextureTarget::_2D:
        case TextureTarget::CubeMapNegativeX:
        case TextureTarget::CubeMapNegativeY:
        case TextureTarget::CubeMapNegativeZ:
        case TextureTarget::CubeMapPositiveX:
        case TextureTarget::CubeMapPositiveY:
        case TextureTarget::CubeMapPositiveZ:
            return true;

        case TextureTarget::Rectangle:
            return context->getExtensions().textureRectangleANGLE;

        default:
            return false;
    }
}

bool IsValidCopyTextureDestinationTarget(const Context *context,
                                         TextureType textureType,
                                         TextureTarget target)
{
    return TextureTargetToType(target) == textureType;
}

bool IsValidCopyTextureSourceTarget(const Context *context, TextureType type)
{
    switch (type)
    {
        case TextureType::_2D:
            return true;
        case TextureType::Rectangle:
            return context->getExtensions().textureRectangleANGLE;
        case TextureType::External:
            return context->getExtensions().EGLImageExternalOES;
        case TextureType::VideoImage:
            return context->getExtensions().videoTextureWEBGL;
        default:
            return false;
    }
}

bool IsValidCopyTextureSourceLevel(const Context *context, TextureType type, GLint level)
{
    if (!ValidMipLevel(context, type, level))
    {
        return false;
    }

    if (level > 0 && context->getClientVersion() < ES_3_0)
    {
        return false;
    }

    return true;
}

bool IsValidCopyTextureDestinationLevel(const Context *context,
                                        angle::EntryPoint entryPoint,
                                        TextureType type,
                                        GLint level,
                                        GLsizei width,
                                        GLsizei height,
                                        bool isSubImage)
{
    if (!ValidMipLevel(context, type, level))
    {
        return false;
    }

    if (!ValidImageSizeParameters(context, entryPoint, type, level, width, height, 1, isSubImage))
    {
        return false;
    }

    const Caps &caps = context->getCaps();
    switch (type)
    {
        case TextureType::_2D:
            return width <= (caps.max2DTextureSize >> level) &&
                   height <= (caps.max2DTextureSize >> level);
        case TextureType::Rectangle:
            ASSERT(level == 0);
            return width <= (caps.max2DTextureSize >> level) &&
                   height <= (caps.max2DTextureSize >> level);

        case TextureType::CubeMap:
            return width <= (caps.maxCubeMapTextureSize >> level) &&
                   height <= (caps.maxCubeMapTextureSize >> level);
        default:
            return true;
    }
}

bool IsValidStencilFunc(GLenum func)
{
    switch (func)
    {
        case GL_NEVER:
        case GL_ALWAYS:
        case GL_LESS:
        case GL_LEQUAL:
        case GL_EQUAL:
        case GL_GEQUAL:
        case GL_GREATER:
        case GL_NOTEQUAL:
            return true;

        default:
            return false;
    }
}

bool IsValidStencilFace(GLenum face)
{
    switch (face)
    {
        case GL_FRONT:
        case GL_BACK:
        case GL_FRONT_AND_BACK:
            return true;

        default:
            return false;
    }
}

bool IsValidStencilOp(GLenum op)
{
    switch (op)
    {
        case GL_ZERO:
        case GL_KEEP:
        case GL_REPLACE:
        case GL_INCR:
        case GL_DECR:
        case GL_INVERT:
        case GL_INCR_WRAP:
        case GL_DECR_WRAP:
            return true;

        default:
            return false;
    }
}

static inline bool Valid1to4ComponentFloatColorBufferFormat(const Context *context, GLenum format)
{
    return (context->getExtensions().textureFloatOES &&
            (format == GL_RGBA32F || format == GL_RGB32F || format == GL_RG32F ||
             format == GL_R32F)) ||
           (context->getExtensions().textureHalfFloatOES &&
            (format == GL_RGBA16F || format == GL_RGB16F || format == GL_RG16F ||
             format == GL_R16F));
}

static inline bool Valid2to4ComponentFloatColorBufferFormat(const Context *context, GLenum format)
{
    return (context->getExtensions().textureFloatOES &&
            (format == GL_RGBA32F || format == GL_RGB32F || format == GL_RG32F)) ||
           (context->getExtensions().textureHalfFloatOES &&
            (format == GL_RGBA16F || format == GL_RGB16F || format == GL_RG16F));
}

static inline bool Valid3to4ComponentFloatColorBufferFormat(const Context *context, GLenum format)
{
    return (context->getExtensions().textureFloatOES &&
            (format == GL_RGBA32F || format == GL_RGB32F)) ||
           (context->getExtensions().textureHalfFloatOES &&
            (format == GL_RGBA16F || format == GL_RGB16F));
}

static inline bool Valid4ComponentFloatColorBufferFormat(const Context *context, GLenum format)
{
    return (context->getExtensions().textureFloatOES && format == GL_RGBA32F) ||
           (context->getExtensions().textureHalfFloatOES && format == GL_RGBA16F);
}

bool ValidateES2CopyTexImageParameters(const Context *context,
                                       angle::EntryPoint entryPoint,
                                       TextureTarget target,
                                       GLint level,
                                       GLenum internalformat,
                                       bool isSubImage,
                                       GLint xoffset,
                                       GLint yoffset,
                                       GLint x,
                                       GLint y,
                                       GLsizei width,
                                       GLsizei height,
                                       GLint border)
{
    if (!ValidTexture2DDestinationTarget(context, target))
    {
        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidTextureTarget);
        return false;
    }

    TextureType texType = TextureTargetToType(target);
    if (!ValidImageSizeParameters(context, entryPoint, texType, level, width, height, 1,
                                  isSubImage))
    {
        // Error is already handled.
        return false;
    }

    Format textureFormat = Format::Invalid();
    if (!ValidateCopyTexImageParametersBase(context, entryPoint, target, level, internalformat,
                                            isSubImage, xoffset, yoffset, 0, x, y, width, height,
                                            border, &textureFormat))
    {
        return false;
    }

    ASSERT(textureFormat.valid() || !isSubImage);

    const Framebuffer *framebuffer = context->getState().getReadFramebuffer();
    GLenum colorbufferFormat =
        framebuffer->getReadColorAttachment()->getFormat().info->sizedInternalFormat;
    const auto &formatInfo = *textureFormat.info;

    // ValidateCopyTexImageParametersBase rejects compressed formats with GL_INVALID_OPERATION.
    ASSERT(!formatInfo.compressed);
    ASSERT(!GetInternalFormatInfo(internalformat, GL_UNSIGNED_BYTE).compressed);

    // ValidateCopyTexImageParametersBase rejects depth formats with GL_INVALID_OPERATION.
    ASSERT(!formatInfo.depthBits);
    ASSERT(!GetInternalFormatInfo(internalformat, GL_UNSIGNED_BYTE).depthBits);

    // [OpenGL ES 2.0.24] table 3.9
    if (isSubImage)
    {
        switch (formatInfo.format)
        {
            case GL_ALPHA:
                if (colorbufferFormat != GL_ALPHA8_EXT && colorbufferFormat != GL_RGBA4 &&
                    colorbufferFormat != GL_RGB5_A1 && colorbufferFormat != GL_RGBA8_OES &&
                    colorbufferFormat != GL_BGRA8_EXT && colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    !Valid4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_LUMINANCE:
                if (colorbufferFormat != GL_R8_EXT && colorbufferFormat != GL_RG8_EXT &&
                    colorbufferFormat != GL_RGB565 && colorbufferFormat != GL_RGB8_OES &&
                    colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid1to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_RED_EXT:
                if (colorbufferFormat != GL_R8_EXT && colorbufferFormat != GL_RG8_EXT &&
                    colorbufferFormat != GL_RGB565 && colorbufferFormat != GL_RGB8_OES &&
                    colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_R32F &&
                    colorbufferFormat != GL_RG32F && colorbufferFormat != GL_RGB32F &&
                    colorbufferFormat != GL_RGBA32F && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid1to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_RG_EXT:
                if (colorbufferFormat != GL_RG8_EXT && colorbufferFormat != GL_RGB565 &&
                    colorbufferFormat != GL_RGB8_OES && colorbufferFormat != GL_RGBA4 &&
                    colorbufferFormat != GL_RGB5_A1 && colorbufferFormat != GL_RGBA8_OES &&
                    colorbufferFormat != GL_RG32F && colorbufferFormat != GL_RGB32F &&
                    colorbufferFormat != GL_RGBA32F && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid2to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_RGB:
                if (colorbufferFormat != GL_RGB565 && colorbufferFormat != GL_RGB8_OES &&
                    colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_RGB32F &&
                    colorbufferFormat != GL_RGBA32F && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid3to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_LUMINANCE_ALPHA:
            case GL_RGBA:
                if (colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_RGBA32F &&
                    colorbufferFormat != GL_BGRA8_EXT && colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    !Valid4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            default:
                context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                return false;
        }

        if (formatInfo.type == GL_FLOAT && !context->getExtensions().textureFloatOES)
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
            return false;
        }
    }
    else
    {
        switch (internalformat)
        {
            case GL_ALPHA:
                if (colorbufferFormat != GL_ALPHA8_EXT && colorbufferFormat != GL_RGBA4 &&
                    colorbufferFormat != GL_RGB5_A1 && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    !Valid4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_LUMINANCE:
            case GL_RED_EXT:
                if (colorbufferFormat != GL_R8_EXT && colorbufferFormat != GL_RG8_EXT &&
                    colorbufferFormat != GL_RGB565 && colorbufferFormat != GL_RGB8_OES &&
                    colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_BGRA8_EXT && colorbufferFormat != GL_RGBA8_OES &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid1to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_RG_EXT:
                if (colorbufferFormat != GL_RG8_EXT && colorbufferFormat != GL_RGB565 &&
                    colorbufferFormat != GL_RGB8_OES && colorbufferFormat != GL_RGBA4 &&
                    colorbufferFormat != GL_RGB5_A1 && colorbufferFormat != GL_BGRA8_EXT &&
                    colorbufferFormat != GL_RGBA8_OES && colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid2to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_RGB:
                if (colorbufferFormat != GL_RGB565 && colorbufferFormat != GL_RGB8_OES &&
                    colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_BGRA8_EXT && colorbufferFormat != GL_RGBA8_OES &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX &&
                    colorbufferFormat != GL_BGRX8_ANGLEX && colorbufferFormat != GL_RGBX8_ANGLE &&
                    !Valid3to4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            case GL_LUMINANCE_ALPHA:
            case GL_RGBA:
                if (colorbufferFormat != GL_RGBA4 && colorbufferFormat != GL_RGB5_A1 &&
                    colorbufferFormat != GL_BGRA8_EXT && colorbufferFormat != GL_RGBA8_OES &&
                    colorbufferFormat != GL_BGR5_A1_ANGLEX && colorbufferFormat != GL_RGBA16F &&
                    !Valid4ComponentFloatColorBufferFormat(context, colorbufferFormat))
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }
                break;
            default:
                context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                          internalformat);
                return false;
        }
    }

    // If width or height is zero, it is a no-op.  Return false without setting an error.
    return (width > 0 && height > 0);
}

bool ValidCap(const Context *context, GLenum cap, bool queryOnly)
{
    switch (cap)
    {
        // EXT_multisample_compatibility
        case GL_MULTISAMPLE_EXT:
        case GL_SAMPLE_ALPHA_TO_ONE_EXT:
            return context->getExtensions().multisampleCompatibilityEXT;

        case GL_CULL_FACE:
        case GL_POLYGON_OFFSET_FILL:
        case GL_SAMPLE_ALPHA_TO_COVERAGE:
        case GL_SAMPLE_COVERAGE:
        case GL_SCISSOR_TEST:
        case GL_STENCIL_TEST:
        case GL_DEPTH_TEST:
        case GL_BLEND:
        case GL_DITHER:
            return true;

        case GL_PRIMITIVE_RESTART_FIXED_INDEX:
        case GL_RASTERIZER_DISCARD:
            return (context->getClientMajorVersion() >= 3);

        case GL_DEBUG_OUTPUT_SYNCHRONOUS:
        case GL_DEBUG_OUTPUT:
            return context->getExtensions().debugKHR;

        case GL_BIND_GENERATES_RESOURCE_CHROMIUM:
            return queryOnly && context->getExtensions().bindGeneratesResourceCHROMIUM;

        case GL_CLIENT_ARRAYS_ANGLE:
            return queryOnly && context->getExtensions().clientArraysANGLE;

        case GL_FRAMEBUFFER_SRGB_EXT:
            return context->getExtensions().sRGBWriteControlEXT;

        case GL_SAMPLE_MASK:
            return context->getClientVersion() >= Version(3, 1);

        case GL_ROBUST_RESOURCE_INITIALIZATION_ANGLE:
            return queryOnly && context->getExtensions().robustResourceInitializationANGLE;

        case GL_TEXTURE_RECTANGLE_ANGLE:
            return context->isWebGL();

        // GL_APPLE_clip_distance/GL_EXT_clip_cull_distance
        case GL_CLIP_DISTANCE0_EXT:
        case GL_CLIP_DISTANCE1_EXT:
        case GL_CLIP_DISTANCE2_EXT:
        case GL_CLIP_DISTANCE3_EXT:
        case GL_CLIP_DISTANCE4_EXT:
        case GL_CLIP_DISTANCE5_EXT:
        case GL_CLIP_DISTANCE6_EXT:
        case GL_CLIP_DISTANCE7_EXT:
            if (context->getExtensions().clipDistanceAPPLE ||
                context->getExtensions().clipCullDistanceEXT)
            {
                return true;
            }
            break;
        case GL_SAMPLE_SHADING:
            return context->getExtensions().sampleShadingOES;
        case GL_SHADING_RATE_PRESERVE_ASPECT_RATIO_QCOM:
            return context->getExtensions().shadingRateQCOM;

        // COLOR_LOGIC_OP is in GLES1, but exposed through an ANGLE extension.
        case GL_COLOR_LOGIC_OP:
            return context->getClientVersion() < Version(2, 0) ||
                   context->getExtensions().logicOpANGLE;

        default:
            break;
    }

    // GLES1 emulation: GLES1-specific caps after this point
    if (context->getClientVersion().major != 1)
    {
        return false;
    }

    switch (cap)
    {
        case GL_ALPHA_TEST:
        case GL_VERTEX_ARRAY:
        case GL_NORMAL_ARRAY:
        case GL_COLOR_ARRAY:
        case GL_TEXTURE_COORD_ARRAY:
        case GL_TEXTURE_2D:
        case GL_LIGHTING:
        case GL_LIGHT0:
        case GL_LIGHT1:
        case GL_LIGHT2:
        case GL_LIGHT3:
        case GL_LIGHT4:
        case GL_LIGHT5:
        case GL_LIGHT6:
        case GL_LIGHT7:
        case GL_NORMALIZE:
        case GL_RESCALE_NORMAL:
        case GL_COLOR_MATERIAL:
        case GL_CLIP_PLANE0:
        case GL_CLIP_PLANE1:
        case GL_CLIP_PLANE2:
        case GL_CLIP_PLANE3:
        case GL_CLIP_PLANE4:
        case GL_CLIP_PLANE5:
        case GL_FOG:
        case GL_POINT_SMOOTH:
        case GL_LINE_SMOOTH:
            return context->getClientVersion() < Version(2, 0);
        case GL_POINT_SIZE_ARRAY_OES:
            return context->getClientVersion() < Version(2, 0) &&
                   context->getExtensions().pointSizeArrayOES;
        case GL_TEXTURE_CUBE_MAP:
            return context->getClientVersion() < Version(2, 0) &&
                   context->getExtensions().textureCubeMapOES;
        case GL_POINT_SPRITE_OES:
            return context->getClientVersion() < Version(2, 0) &&
                   context->getExtensions().pointSpriteOES;
        default:
            return false;
    }
}

// Return true if a character belongs to the ASCII subset as defined in GLSL ES 1.0 spec section
// 3.1.
bool IsValidESSLCharacter(unsigned char c)
{
    // Printing characters are valid except " $ ` @ \ ' DEL.
    if (c >= 32 && c <= 126 && c != '"' && c != '$' && c != '`' && c != '@' && c != '\\' &&
        c != '\'')
    {
        return true;
    }

    // Horizontal tab, line feed, vertical tab, form feed, carriage return are also valid.
    if (c >= 9 && c <= 13)
    {
        return true;
    }

    return false;
}

bool IsValidESSLString(const char *str, size_t len)
{
    for (size_t i = 0; i < len; i++)
    {
        if (!IsValidESSLCharacter(str[i]))
        {
            return false;
        }
    }

    return true;
}

bool ValidateWebGLNamePrefix(const Context *context,
                             angle::EntryPoint entryPoint,
                             const GLchar *name)
{
    ASSERT(context->isWebGL());

    // WebGL 1.0 [Section 6.16] GLSL Constructs
    // Identifiers starting with "webgl_" and "_webgl_" are reserved for use by WebGL.
    if (strncmp(name, "webgl_", 6) == 0 || strncmp(name, "_webgl_", 7) == 0)
    {
        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                 kWebglBindAttribLocationReservedPrefix);
        return false;
    }

    return true;
}

bool ValidateWebGLNameLength(const Context *context, angle::EntryPoint entryPoint, size_t length)
{
    ASSERT(context->isWebGL());

    if (context->isWebGL1() && length > 256)
    {
        // WebGL 1.0 [Section 6.21] Maxmimum Uniform and Attribute Location Lengths
        // WebGL imposes a limit of 256 characters on the lengths of uniform and attribute
        // locations.
        context->validationError(entryPoint, GL_INVALID_VALUE, kWebglNameLengthLimitExceeded);

        return false;
    }
    else if (length > 1024)
    {
        // WebGL 2.0 [Section 4.3.2] WebGL 2.0 imposes a limit of 1024 characters on the lengths of
        // uniform and attribute locations.
        context->validationError(entryPoint, GL_INVALID_VALUE, kWebgl2NameLengthLimitExceeded);
        return false;
    }

    return true;
}

bool ValidBlendFunc(const Context *context, GLenum val)
{
    const Extensions &ext = context->getExtensions();

    // these are always valid for src and dst.
    switch (val)
    {
        case GL_ZERO:
        case GL_ONE:
        case GL_SRC_COLOR:
        case GL_ONE_MINUS_SRC_COLOR:
        case GL_DST_COLOR:
        case GL_ONE_MINUS_DST_COLOR:
        case GL_SRC_ALPHA:
        case GL_ONE_MINUS_SRC_ALPHA:
        case GL_DST_ALPHA:
        case GL_ONE_MINUS_DST_ALPHA:
        case GL_CONSTANT_COLOR:
        case GL_ONE_MINUS_CONSTANT_COLOR:
        case GL_CONSTANT_ALPHA:
        case GL_ONE_MINUS_CONSTANT_ALPHA:
            return true;

        // EXT_blend_func_extended.
        case GL_SRC1_COLOR_EXT:
        case GL_SRC1_ALPHA_EXT:
        case GL_ONE_MINUS_SRC1_COLOR_EXT:
        case GL_ONE_MINUS_SRC1_ALPHA_EXT:
        case GL_SRC_ALPHA_SATURATE_EXT:
            return ext.blendFuncExtendedEXT;

        default:
            return false;
    }
}

bool ValidSrcBlendFunc(const Context *context, GLenum val)
{
    if (ValidBlendFunc(context, val))
        return true;

    if (val == GL_SRC_ALPHA_SATURATE)
        return true;

    return false;
}

bool ValidDstBlendFunc(const Context *context, GLenum val)
{
    if (ValidBlendFunc(context, val))
        return true;

    if (val == GL_SRC_ALPHA_SATURATE)
    {
        if (context->getClientMajorVersion() >= 3)
            return true;
    }

    return false;
}

bool ValidateES2TexImageParameters(const Context *context,
                                   angle::EntryPoint entryPoint,
                                   TextureTarget target,
                                   GLint level,
                                   GLenum internalformat,
                                   bool isCompressed,
                                   bool isSubImage,
                                   GLint xoffset,
                                   GLint yoffset,
                                   GLsizei width,
                                   GLsizei height,
                                   GLint border,
                                   GLenum format,
                                   GLenum type,
                                   GLsizei imageSize,
                                   const void *pixels)
{
    if (!ValidTexture2DDestinationTarget(context, target))
    {
        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidTextureTarget);
        return false;
    }

    return ValidateES2TexImageParametersBase(context, entryPoint, target, level, internalformat,
                                             isCompressed, isSubImage, xoffset, yoffset, width,
                                             height, border, format, type, imageSize, pixels);
}

}  // anonymous namespace

bool ValidateES2TexImageParametersBase(const Context *context,
                                       angle::EntryPoint entryPoint,
                                       TextureTarget target,
                                       GLint level,
                                       GLenum internalformat,
                                       bool isCompressed,
                                       bool isSubImage,
                                       GLint xoffset,
                                       GLint yoffset,
                                       GLsizei width,
                                       GLsizei height,
                                       GLint border,
                                       GLenum format,
                                       GLenum type,
                                       GLsizei imageSize,
                                       const void *pixels)
{

    TextureType texType = TextureTargetToType(target);
    if (!ValidImageSizeParameters(context, entryPoint, texType, level, width, height, 1,
                                  isSubImage))
    {
        // Error already handled.
        return false;
    }

    if (!ValidMipLevel(context, texType, level))
    {
        context->validationError(entryPoint, GL_INVALID_VALUE, kInvalidMipLevel);
        return false;
    }

    if ((xoffset < 0 || std::numeric_limits<GLsizei>::max() - xoffset < width) ||
        (yoffset < 0 || std::numeric_limits<GLsizei>::max() - yoffset < height))
    {
        context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
        return false;
    }

    const Caps &caps = context->getCaps();

    switch (texType)
    {
        case TextureType::_2D:
        case TextureType::External:
        case TextureType::VideoImage:
            if (width > (caps.max2DTextureSize >> level) ||
                height > (caps.max2DTextureSize >> level))
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            break;

        case TextureType::Rectangle:
            ASSERT(level == 0);
            if (width > caps.maxRectangleTextureSize || height > caps.maxRectangleTextureSize)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            if (isCompressed)
            {
                context->validationError(entryPoint, GL_INVALID_ENUM, kRectangleTextureCompressed);
                return false;
            }
            break;

        case TextureType::CubeMap:
            if (!isSubImage && width != height)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE,
                                         kCubemapFacesEqualDimensions);
                return false;
            }

            if (width > (caps.maxCubeMapTextureSize >> level) ||
                height > (caps.maxCubeMapTextureSize >> level))
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            break;

        default:
            context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidTextureTarget);
            return false;
    }

    Texture *texture = context->getTextureByType(texType);
    if (!texture)
    {
        context->validationError(entryPoint, GL_INVALID_OPERATION, kBufferNotBound);
        return false;
    }

    // Verify zero border
    if (border != 0)
    {
        context->validationError(entryPoint, GL_INVALID_VALUE, kInvalidBorder);
        return false;
    }

    bool nonEqualFormatsAllowed = false;

    if (isCompressed)
    {
        GLenum actualInternalFormat =
            isSubImage ? texture->getFormat(target, level).info->sizedInternalFormat
                       : internalformat;

        const InternalFormat &internalFormatInfo = GetSizedInternalFormatInfo(actualInternalFormat);

        if (!internalFormatInfo.compressed && !internalFormatInfo.paletted)
        {
            context->validationErrorF(entryPoint, GL_INVALID_ENUM, kInvalidInternalFormat,
                                      internalformat);
            return false;
        }

        if (!internalFormatInfo.textureSupport(context->getClientVersion(),
                                               context->getExtensions()))
        {
            context->validationErrorF(entryPoint, GL_INVALID_ENUM, kInvalidInternalFormat,
                                      internalformat);
            return false;
        }

        if (isSubImage)
        {
            // From OpenGL ES Version 1.1.12, section 3.7.4 Compressed Paletted
            // Textures:
            //
            // Subimages may not be specified for compressed paletted textures.
            // Calling CompressedTexSubImage2D with any of the PALETTE*
            // arguments in table 3.11 will generate an INVALID OPERATION error.
            if (internalFormatInfo.paletted)
            {
                context->validationErrorF(entryPoint, GL_INVALID_OPERATION, kInvalidInternalFormat,
                                          internalformat);
                return false;
            }

            // From the OES_compressed_ETC1_RGB8_texture spec:
            //
            // INVALID_OPERATION is generated by CompressedTexSubImage2D, TexSubImage2D, or
            // CopyTexSubImage2D if the texture image <level> bound to <target> has internal format
            // ETC1_RGB8_OES.
            //
            // This is relaxed if GL_EXT_compressed_ETC1_RGB8_sub_texture is supported.
            if (IsETC1Format(actualInternalFormat) &&
                !context->getExtensions().compressedETC1RGB8SubTextureEXT)
            {
                context->validationErrorF(entryPoint, GL_INVALID_OPERATION, kInvalidInternalFormat,
                                          internalformat);
                return false;
            }

            if (!ValidCompressedSubImageSize(context, actualInternalFormat, xoffset, yoffset, 0,
                                             width, height, 1, texture->getWidth(target, level),
                                             texture->getHeight(target, level),
                                             texture->getDepth(target, level)))
            {
                context->validationError(entryPoint, GL_INVALID_OPERATION,
                                         kInvalidCompressedImageSize);
                return false;
            }

            if (format != actualInternalFormat)
            {
                context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                return false;
            }
        }
        else
        {
            if (!ValidCompressedImageSize(context, actualInternalFormat, level, width, height, 1))
            {
                context->validationError(entryPoint, GL_INVALID_OPERATION,
                                         kInvalidCompressedImageSize);
                return false;
            }
        }
    }
    else
    {
        // validate <type> by itself (used as secondary key below)
        switch (type)
        {
            case GL_UNSIGNED_BYTE:
            case GL_UNSIGNED_SHORT_5_6_5:
            case GL_UNSIGNED_SHORT_4_4_4_4:
            case GL_UNSIGNED_SHORT_5_5_5_1:
            case GL_UNSIGNED_SHORT:
            case GL_UNSIGNED_INT:
            case GL_UNSIGNED_INT_24_8_OES:
            case GL_HALF_FLOAT_OES:
            case GL_FLOAT:
                break;
            case GL_UNSIGNED_INT_2_10_10_10_REV_EXT:
                if (!context->getExtensions().textureType2101010REVEXT)
                {
                    context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported, type);
                    return false;
                }
                break;
            default:
                context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidType);
                return false;
        }

        // validate <format> + <type> combinations
        // - invalid <format> -> sets INVALID_ENUM
        // - invalid <format>+<type> combination -> sets INVALID_OPERATION
        switch (format)
        {
            case GL_ALPHA:
            case GL_LUMINANCE:
            case GL_LUMINANCE_ALPHA:
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                    case GL_FLOAT:
                    case GL_HALF_FLOAT_OES:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_RED:
            case GL_RG:
                if (!context->getExtensions().textureRgEXT)
                {
                    context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                              format);
                    return false;
                }
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                        break;
                    case GL_FLOAT:
                        if (!context->getExtensions().textureFloatOES)
                        {
                            context->validationErrorF(entryPoint, GL_INVALID_ENUM,
                                                      kEnumNotSupported, type);
                            return false;
                        }
                        break;
                    case GL_HALF_FLOAT_OES:
                        if (!context->getExtensions().textureFloatOES &&
                            !context->getExtensions().textureHalfFloatOES)
                        {
                            context->validationErrorF(entryPoint, GL_INVALID_ENUM,
                                                      kEnumNotSupported, type);
                            return false;
                        }
                        break;
                    case GL_SHORT:
                    case GL_UNSIGNED_SHORT:
                        if (!context->getExtensions().textureNorm16EXT)
                        {
                            context->validationErrorF(entryPoint, GL_INVALID_ENUM,
                                                      kEnumNotSupported, type);
                            return false;
                        }
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_RGB:
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                    case GL_UNSIGNED_SHORT_5_6_5:
                    case GL_UNSIGNED_INT_2_10_10_10_REV_EXT:
                    case GL_FLOAT:
                    case GL_HALF_FLOAT_OES:
                        break;
                    case GL_SHORT:
                    case GL_UNSIGNED_SHORT:
                        if (!context->getExtensions().textureNorm16EXT)
                        {
                            context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                     kMismatchedTypeAndFormat);
                            return false;
                        }
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_RGBA:
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                    case GL_UNSIGNED_SHORT_4_4_4_4:
                    case GL_UNSIGNED_SHORT_5_5_5_1:
                    case GL_FLOAT:
                    case GL_HALF_FLOAT_OES:
                    case GL_UNSIGNED_INT_2_10_10_10_REV_EXT:
                        break;
                    case GL_SHORT:
                    case GL_UNSIGNED_SHORT:
                        if (!context->getExtensions().textureNorm16EXT)
                        {
                            context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                     kMismatchedTypeAndFormat);
                            return false;
                        }
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_BGRA_EXT:
                if (!context->getExtensions().textureFormatBGRA8888EXT)
                {
                    context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                              format);
                    return false;
                }
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_SRGB_EXT:
            case GL_SRGB_ALPHA_EXT:
                if (!context->getExtensions().sRGBEXT)
                {
                    context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                              format);
                    return false;
                }
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_DEPTH_COMPONENT:
                switch (type)
                {
                    case GL_UNSIGNED_SHORT:
                    case GL_UNSIGNED_INT:
                        break;
                    case GL_FLOAT:
                        if (!context->getExtensions().depthBufferFloat2NV)
                        {
                            context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                     kMismatchedTypeAndFormat);
                            return false;
                        }
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_DEPTH_STENCIL_OES:
                switch (type)
                {
                    case GL_UNSIGNED_INT_24_8_OES:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            case GL_STENCIL_INDEX:
                switch (type)
                {
                    case GL_UNSIGNED_BYTE:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                }
                break;
            default:
                context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported, format);
                return false;
        }

        switch (format)
        {
            case GL_DEPTH_COMPONENT:
            case GL_DEPTH_STENCIL_OES:
                if (!context->getExtensions().depthTextureANGLE &&
                    !((context->getExtensions().packedDepthStencilOES ||
                       context->getExtensions().depthTextureCubeMapOES) &&
                      context->getExtensions().depthTextureOES))
                {
                    context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                              format);
                    return false;
                }

                switch (target)
                {
                    case TextureTarget::_2D:
                        break;
                    case TextureTarget::CubeMapNegativeX:
                    case TextureTarget::CubeMapNegativeY:
                    case TextureTarget::CubeMapNegativeZ:
                    case TextureTarget::CubeMapPositiveX:
                    case TextureTarget::CubeMapPositiveY:
                    case TextureTarget::CubeMapPositiveZ:
                        if (!context->getExtensions().depthTextureCubeMapOES)
                        {
                            context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                     kMismatchedTargetAndFormat);
                            return false;
                        }
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTargetAndFormat);
                        return false;
                }

                // OES_depth_texture supports loading depth data and multiple levels,
                // but ANGLE_depth_texture does not
                if (!context->getExtensions().depthTextureOES)
                {
                    if (pixels != nullptr)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kPixelDataNotNull);
                        return false;
                    }
                    if (level != 0)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION, kLevelNotZero);
                        return false;
                    }
                }
                break;
            case GL_STENCIL_INDEX:
                if (!context->getExtensions().textureStencil8OES)
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormat);
                    return false;
                }

                switch (target)
                {
                    case TextureTarget::_2D:
                    case TextureTarget::_2DArray:
                    case TextureTarget::CubeMapNegativeX:
                    case TextureTarget::CubeMapNegativeY:
                    case TextureTarget::CubeMapNegativeZ:
                    case TextureTarget::CubeMapPositiveX:
                    case TextureTarget::CubeMapPositiveY:
                    case TextureTarget::CubeMapPositiveZ:
                        break;
                    default:
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTargetAndFormat);
                        return false;
                }

                if (internalformat != GL_STENCIL_INDEX8)
                {
                    context->validationError(entryPoint, GL_INVALID_OPERATION,
                                             kMismatchedTargetAndFormat);
                    return false;
                }
                break;
            default:
                break;
        }

        if (!isSubImage)
        {
            switch (internalformat)
            {
                // Core ES 2.0 formats
                case GL_ALPHA:
                case GL_LUMINANCE:
                case GL_LUMINANCE_ALPHA:
                case GL_RGB:
                case GL_RGBA:
                    break;

                case GL_RGBA32F:
                    if (!context->getExtensions().colorBufferFloatRgbaCHROMIUM)
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }

                    nonEqualFormatsAllowed = true;

                    if (type != GL_FLOAT)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                    }
                    if (format != GL_RGBA)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                    }
                    break;

                case GL_RGB32F:
                    if (!context->getExtensions().colorBufferFloatRgbCHROMIUM)
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }

                    nonEqualFormatsAllowed = true;

                    if (type != GL_FLOAT)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                    }
                    if (format != GL_RGB)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                    }
                    break;

                case GL_BGRA_EXT:
                    if (!context->getExtensions().textureFormatBGRA8888EXT)
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }
                    break;

                case GL_DEPTH_COMPONENT:
                    if (!(context->getExtensions().depthTextureAny()))
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }
                    break;

                case GL_DEPTH_STENCIL:
                    if (!(context->getExtensions().depthTextureANGLE ||
                          context->getExtensions().packedDepthStencilOES ||
                          context->getExtensions().depthTextureCubeMapOES))
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }
                    break;

                case GL_STENCIL_INDEX8:
                    if (!context->getExtensions().textureStencil8OES)
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }
                    break;

                case GL_RED:
                case GL_RG:
                    if (!context->getExtensions().textureRgEXT)
                    {
                        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
                        return false;
                    }
                    break;

                case GL_SRGB_EXT:
                case GL_SRGB_ALPHA_EXT:
                    if (!context->getExtensions().sRGBEXT)
                    {
                        context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                                  internalformat);
                        return false;
                    }
                    break;

                case GL_RGB10_A2_EXT:
                    if (!context->getExtensions().textureType2101010REVEXT)
                    {
                        context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                                  internalformat);
                        return false;
                    }

                    if (type != GL_UNSIGNED_INT_2_10_10_10_REV_EXT || format != GL_RGBA)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kMismatchedTypeAndFormat);
                        return false;
                    }

                    nonEqualFormatsAllowed = true;

                    break;

                case GL_RGB5_A1:
                    if (context->getExtensions().textureType2101010REVEXT &&
                        type == GL_UNSIGNED_INT_2_10_10_10_REV_EXT && format == GL_RGBA)
                    {
                        nonEqualFormatsAllowed = true;
                    }

                    break;

                case GL_RGBX8_ANGLE:
                    if (context->getExtensions().rgbxInternalFormatANGLE &&
                        type == GL_UNSIGNED_BYTE && format == GL_RGB)
                    {
                        nonEqualFormatsAllowed = true;
                    }

                    break;

                case GL_R16_EXT:
                case GL_RG16_EXT:
                case GL_RGB16_EXT:
                case GL_RGBA16_EXT:
                case GL_R16_SNORM_EXT:
                case GL_RG16_SNORM_EXT:
                case GL_RGB16_SNORM_EXT:
                case GL_RGBA16_SNORM_EXT:
                    if (!context->getExtensions().textureNorm16EXT)
                    {
                        context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                                  internalformat);
                        return false;
                    }
                    break;
                default:
                    // Compressed formats are not valid internal formats for glTexImage*D
                    context->validationErrorF(entryPoint, GL_INVALID_VALUE, kInvalidInternalFormat,
                                              internalformat);
                    return false;
            }
        }

        if (type == GL_FLOAT)
        {
            if (!context->getExtensions().textureFloatOES)
            {
                context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported, type);
                return false;
            }
        }
        else if (type == GL_HALF_FLOAT_OES)
        {
            if (!context->getExtensions().textureHalfFloatOES)
            {
                context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported, type);
                return false;
            }
        }
    }

    if (isSubImage)
    {
        const InternalFormat &textureInternalFormat = *texture->getFormat(target, level).info;
        if (textureInternalFormat.internalFormat == GL_NONE)
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidTextureLevel);
            return false;
        }

        if (format != textureInternalFormat.format)
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, err::kTextureFormatMismatch);
            return false;
        }

        if (context->isWebGL())
        {
            if (GetInternalFormatInfo(format, type).sizedInternalFormat !=
                textureInternalFormat.sizedInternalFormat)
            {
                context->validationError(entryPoint, GL_INVALID_OPERATION, kTextureTypeMismatch);
                return false;
            }
        }

        if (static_cast<size_t>(xoffset + width) > texture->getWidth(target, level) ||
            static_cast<size_t>(yoffset + height) > texture->getHeight(target, level))
        {
            context->validationError(entryPoint, GL_INVALID_VALUE, kOffsetOverflow);
            return false;
        }

        if (width > 0 && height > 0 && pixels == nullptr &&
            context->getState().getTargetBuffer(BufferBinding::PixelUnpack) == nullptr)
        {
            context->validationError(entryPoint, GL_INVALID_VALUE, kPixelDataNull);
            return false;
        }
    }
    else
    {
        if (texture->getImmutableFormat())
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, kTextureIsImmutable);
            return false;
        }
    }

    // From GL_CHROMIUM_color_buffer_float_rgb[a]:
    // GL_RGB[A] / GL_RGB[A]32F becomes an allowable format / internalformat parameter pair for
    // TexImage2D. The restriction in section 3.7.1 of the OpenGL ES 2.0 spec that the
    // internalformat parameter and format parameter of TexImage2D must match is lifted for this
    // case.
    if (!isSubImage && !isCompressed && internalformat != format && !nonEqualFormatsAllowed)
    {
        context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidFormatCombination);
        return false;
    }

    GLenum sizeCheckFormat = isSubImage ? format : internalformat;
    return ValidImageDataSize(context, entryPoint, texType, width, height, 1, sizeCheckFormat, type,
                              pixels, imageSize);
}

bool ValidateES2TexStorageParametersBase(const Context *context,
                                         angle::EntryPoint entryPoint,
                                         TextureType target,
                                         GLsizei levels,
                                         GLenum internalformat,
                                         GLsizei width,
                                         GLsizei height)
{
    if (target != TextureType::_2D && target != TextureType::CubeMap &&
        target != TextureType::Rectangle)
    {
        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidTextureTarget);
        return false;
    }

    if (width < 1 || height < 1 || levels < 1)
    {
        context->validationError(entryPoint, GL_INVALID_VALUE, kTextureSizeTooSmall);
        return false;
    }

    if (target == TextureType::CubeMap && width != height)
    {
        context->validationError(entryPoint, GL_INVALID_VALUE, kCubemapFacesEqualDimensions);
        return false;
    }

    if (levels != 1 && levels != log2(std::max(width, height)) + 1)
    {
        context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidMipLevels);
        return false;
    }

    const InternalFormat &formatInfo = GetSizedInternalFormatInfo(internalformat);
    if (formatInfo.format == GL_NONE || formatInfo.type == GL_NONE)
    {
        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
        return false;
    }

    const Caps &caps = context->getCaps();

    switch (target)
    {
        case TextureType::_2D:
            if (width > caps.max2DTextureSize || height > caps.max2DTextureSize)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            break;
        case TextureType::Rectangle:
            if (levels != 1)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kInvalidMipLevel);
                return false;
            }

            if (width > caps.maxRectangleTextureSize || height > caps.maxRectangleTextureSize)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            if (formatInfo.compressed)
            {
                context->validationError(entryPoint, GL_INVALID_ENUM, kRectangleTextureCompressed);
                return false;
            }
            break;
        case TextureType::CubeMap:
            if (width > caps.maxCubeMapTextureSize || height > caps.maxCubeMapTextureSize)
            {
                context->validationError(entryPoint, GL_INVALID_VALUE, kResourceMaxTextureSize);
                return false;
            }
            break;
        case TextureType::InvalidEnum:
            context->validationError(entryPoint, GL_INVALID_ENUM, kEnumInvalid);
            return false;
        default:
            context->validationErrorF(entryPoint, GL_INVALID_ENUM, kEnumNotSupported,
                                      ToGLenum(target));
            return false;
    }

    if (levels != 1 && !context->getExtensions().textureNpotOES)
    {
        if (!isPow2(width) || !isPow2(height))
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, kDimensionsMustBePow2);
            return false;
        }
    }

    if (!formatInfo.textureSupport(context->getClientVersion(), context->getExtensions()))
    {
        context->validationError(entryPoint, GL_INVALID_ENUM, kInvalidFormat);
        return false;
    }

    // Even with OES_texture_npot, some compressed formats may impose extra restrictions.
    if (formatInfo.compressed)
    {
        if (!ValidCompressedImageSize(context, formatInfo.internalFormat, 0, width, height, 1))
        {
            context->validationError(entryPoint, GL_INVALID_OPERATION, kInvalidCompressedImageSize);
            return false;
        }
    }

    switch (internalformat)
    {
        case GL_DEPTH_COMPONENT16:
        case GL_DEPTH_COMPONENT32_OES:
            switch (target)
            {
                case TextureType::_2D:
                    break;
                case TextureType::CubeMap:
                    if (!context->getExtensions().depthTextureCubeMapOES)
                    {
                        context->validationError(entryPoint, GL_INVALID_OPERATION,
                                                 kInvalidTextureTarget);
                        return false;
                    }
                    break;
                default:
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