gecko-dev/dom/canvas/WebGLContextValidate.cpp

696 строки
23 KiB
C++

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "WebGLContext.h"
#include <algorithm>
#include "GLSLANG/ShaderLang.h"
#include "CanvasUtils.h"
#include "GLContext.h"
#include "jsfriendapi.h"
#include "mozilla/CheckedInt.h"
#include "mozilla/Preferences.h"
#include "mozilla/StaticPrefs.h"
#include "nsIObserverService.h"
#include "nsPrintfCString.h"
#include "WebGLActiveInfo.h"
#include "WebGLBuffer.h"
#include "WebGLContextUtils.h"
#include "WebGLFramebuffer.h"
#include "WebGLProgram.h"
#include "WebGLRenderbuffer.h"
#include "WebGLSampler.h"
#include "WebGLShader.h"
#include "WebGLTexture.h"
#include "WebGLUniformLocation.h"
#include "WebGLValidateStrings.h"
#include "WebGLVertexArray.h"
#include "WebGLVertexAttribData.h"
#if defined(MOZ_WIDGET_COCOA)
# include "nsCocoaFeatures.h"
#endif
////////////////////
// Minimum value constants defined in GLES 2.0.25 $6.2 "State Tables":
const uint32_t kMinMaxVertexAttribs = 8; // Page 164
const uint32_t kMinMaxVertexUniformVectors = 128; // Page 164
const uint32_t kMinMaxFragmentUniformVectors = 16; // Page 164
const uint32_t kMinMaxVaryingVectors = 8; // Page 164
const uint32_t kMinMaxVertexTextureImageUnits = 0; // Page 164
const uint32_t kMinMaxFragmentTextureImageUnits = 8; // Page 164
const uint32_t kMinMaxCombinedTextureImageUnits = 8; // Page 164
const uint32_t kMinMaxColorAttachments = 4;
const uint32_t kMinMaxDrawBuffers = 4;
// These few deviate from the spec: (The minimum values in the spec are
// ridiculously low)
const uint32_t kMinMaxTextureSize = 1024; // ES2 spec says `64` (p162)
const uint32_t kMinMaxCubeMapTextureSize = 512; // ES2 spec says `16` (p162)
const uint32_t kMinMaxRenderbufferSize = 1024; // ES2 spec says `1` (p164)
// Minimum value constants defined in GLES 3.0.4 $6.2 "State Tables":
const uint32_t kMinMax3DTextureSize = 256;
const uint32_t kMinMaxArrayTextureLayers = 256;
////////////////////
// "Common" but usable values to avoid WebGL fingerprinting:
const uint32_t kCommonMaxTextureSize = 2048;
const uint32_t kCommonMaxCubeMapTextureSize = 2048;
const uint32_t kCommonMaxRenderbufferSize = 2048;
const uint32_t kCommonMaxVertexTextureImageUnits = 8;
const uint32_t kCommonMaxFragmentTextureImageUnits = 8;
const uint32_t kCommonMaxCombinedTextureImageUnits = 16;
const uint32_t kCommonMaxVertexAttribs = 16;
const uint32_t kCommonMaxVertexUniformVectors = 256;
const uint32_t kCommonMaxFragmentUniformVectors = 224;
const uint32_t kCommonMaxVaryingVectors = 8;
const uint32_t kCommonMaxViewportDims = 4096;
// The following ranges came from a 2013 Moto E and an old macbook.
const float kCommonAliasedPointSizeRangeMin = 1;
const float kCommonAliasedPointSizeRangeMax = 63;
const float kCommonAliasedLineWidthRangeMin = 1;
const float kCommonAliasedLineWidthRangeMax = 1;
template <class T>
static bool RestrictCap(T* const cap, const T restrictedVal) {
if (*cap < restrictedVal) {
return false; // already too low!
}
*cap = restrictedVal;
return true;
}
////////////////////
namespace mozilla {
bool WebGLContext::ValidateBlendEquationEnum(GLenum mode, const char* info) {
switch (mode) {
case LOCAL_GL_FUNC_ADD:
case LOCAL_GL_FUNC_SUBTRACT:
case LOCAL_GL_FUNC_REVERSE_SUBTRACT:
return true;
case LOCAL_GL_MIN:
case LOCAL_GL_MAX:
if (IsWebGL2() ||
IsExtensionEnabled(WebGLExtensionID::EXT_blend_minmax)) {
return true;
}
break;
default:
break;
}
ErrorInvalidEnumInfo(info, mode);
return false;
}
bool WebGLContext::ValidateBlendFuncEnumsCompatibility(GLenum sfactor,
GLenum dfactor,
const char* info) {
bool sfactorIsConstantColor = sfactor == LOCAL_GL_CONSTANT_COLOR ||
sfactor == LOCAL_GL_ONE_MINUS_CONSTANT_COLOR;
bool sfactorIsConstantAlpha = sfactor == LOCAL_GL_CONSTANT_ALPHA ||
sfactor == LOCAL_GL_ONE_MINUS_CONSTANT_ALPHA;
bool dfactorIsConstantColor = dfactor == LOCAL_GL_CONSTANT_COLOR ||
dfactor == LOCAL_GL_ONE_MINUS_CONSTANT_COLOR;
bool dfactorIsConstantAlpha = dfactor == LOCAL_GL_CONSTANT_ALPHA ||
dfactor == LOCAL_GL_ONE_MINUS_CONSTANT_ALPHA;
if ((sfactorIsConstantColor && dfactorIsConstantAlpha) ||
(dfactorIsConstantColor && sfactorIsConstantAlpha)) {
ErrorInvalidOperation(
"%s are mutually incompatible, see section 6.8 in"
" the WebGL 1.0 spec",
info);
return false;
}
return true;
}
bool WebGLContext::ValidateStencilOpEnum(GLenum action, const char* info) {
switch (action) {
case LOCAL_GL_KEEP:
case LOCAL_GL_ZERO:
case LOCAL_GL_REPLACE:
case LOCAL_GL_INCR:
case LOCAL_GL_INCR_WRAP:
case LOCAL_GL_DECR:
case LOCAL_GL_DECR_WRAP:
case LOCAL_GL_INVERT:
return true;
default:
ErrorInvalidEnumInfo(info, action);
return false;
}
}
bool WebGLContext::ValidateFaceEnum(const GLenum face) {
switch (face) {
case LOCAL_GL_FRONT:
case LOCAL_GL_BACK:
case LOCAL_GL_FRONT_AND_BACK:
return true;
default:
ErrorInvalidEnumInfo("face", face);
return false;
}
}
bool WebGLContext::ValidateUniformLocation(
const WebGLUniformLocation* const loc) {
/* GLES 2.0.25, p38:
* If the value of location is -1, the Uniform* commands will silently
* ignore the data passed in, and the current uniform values will not be
* changed.
*/
if (!loc) return false;
if (!ValidateObjectAllowDeleted("loc", *loc)) return false;
if (!mCurrentProgram) {
ErrorInvalidOperation("No program is currently bound.");
return false;
}
return loc->ValidateForProgram(mCurrentProgram);
}
bool WebGLContext::ValidateAttribArraySetter(uint32_t setterElemSize,
uint32_t arrayLength) {
if (IsContextLost()) return false;
if (arrayLength < setterElemSize) {
ErrorInvalidValue("Array must have >= %d elements.", setterElemSize);
return false;
}
return true;
}
bool WebGLContext::ValidateUniformSetter(
const WebGLUniformLocation* const loc, const uint8_t setterElemSize,
const webgl::AttribBaseType setterType) {
if (IsContextLost()) return false;
if (!ValidateUniformLocation(loc)) return false;
if (!loc->ValidateSizeAndType(setterElemSize, setterType)) return false;
return true;
}
bool WebGLContext::ValidateUniformArraySetter(
const WebGLUniformLocation* const loc, const uint8_t setterElemSize,
const webgl::AttribBaseType setterType, const uint32_t setterArraySize,
uint32_t* const out_numElementsToUpload) {
if (IsContextLost()) return false;
if (!ValidateUniformLocation(loc)) return false;
if (!loc->ValidateSizeAndType(setterElemSize, setterType)) return false;
if (!loc->ValidateArrayLength(setterElemSize, setterArraySize)) return false;
const auto& elemCount = loc->mInfo->mActiveInfo->mElemCount;
MOZ_ASSERT(elemCount > loc->mArrayIndex);
const uint32_t uniformElemCount = elemCount - loc->mArrayIndex;
*out_numElementsToUpload =
std::min(uniformElemCount, setterArraySize / setterElemSize);
return true;
}
bool WebGLContext::ValidateUniformMatrixArraySetter(
const WebGLUniformLocation* const loc, const uint8_t setterCols,
const uint8_t setterRows, const webgl::AttribBaseType setterType,
const uint32_t setterArraySize, const bool setterTranspose,
uint32_t* const out_numElementsToUpload) {
const uint8_t setterElemSize = setterCols * setterRows;
if (IsContextLost()) return false;
if (!ValidateUniformLocation(loc)) return false;
if (!loc->ValidateSizeAndType(setterElemSize, setterType)) return false;
if (!loc->ValidateArrayLength(setterElemSize, setterArraySize)) return false;
if (setterTranspose && !IsWebGL2()) {
ErrorInvalidValue("`transpose` must be false.");
return false;
}
const auto& elemCount = loc->mInfo->mActiveInfo->mElemCount;
MOZ_ASSERT(elemCount > loc->mArrayIndex);
const uint32_t uniformElemCount = elemCount - loc->mArrayIndex;
*out_numElementsToUpload =
std::min(uniformElemCount, setterArraySize / setterElemSize);
return true;
}
bool WebGLContext::InitAndValidateGL(FailureReason* const out_failReason) {
MOZ_RELEASE_ASSERT(gl, "GFX: GL not initialized");
// Unconditionally create a new format usage authority. This is
// important when restoring contexts and extensions need to add
// formats back into the authority.
mFormatUsage = CreateFormatUsage(gl);
if (!mFormatUsage) {
*out_failReason = {"FEATURE_FAILURE_WEBGL_FORMAT",
"Failed to create mFormatUsage."};
return false;
}
GLenum error = gl->fGetError();
if (error != LOCAL_GL_NO_ERROR) {
const nsPrintfCString reason(
"GL error 0x%x occurred during OpenGL context"
" initialization, before WebGL initialization!",
error);
*out_failReason = {"FEATURE_FAILURE_WEBGL_GLERR_1", reason};
return false;
}
mDisableExtensions = StaticPrefs::WebGLDisableExtensions();
mLoseContextOnMemoryPressure =
StaticPrefs::WebGLLoseContextOnMemoryPressure();
mCanLoseContextInForeground = StaticPrefs::WebGLCanLoseContextInForeground();
// These are the default values, see 6.2 State tables in the
// OpenGL ES 2.0.25 spec.
mColorWriteMask = 0x0f;
mDriverColorMask = mColorWriteMask;
mColorClearValue[0] = 0.f;
mColorClearValue[1] = 0.f;
mColorClearValue[2] = 0.f;
mColorClearValue[3] = 0.f;
mDepthWriteMask = true;
mDepthClearValue = 1.f;
mStencilClearValue = 0;
mStencilRefFront = 0;
mStencilRefBack = 0;
mLineWidth = 1.0;
/*
// Technically, we should be setting mStencil[...] values to
// `allOnes`, but either ANGLE breaks or the SGX540s on Try break.
GLuint stencilBits = 0;
gl->GetUIntegerv(LOCAL_GL_STENCIL_BITS, &stencilBits);
GLuint allOnes = ~(UINT32_MAX << stencilBits);
mStencilValueMaskFront = allOnes;
mStencilValueMaskBack = allOnes;
mStencilWriteMaskFront = allOnes;
mStencilWriteMaskBack = allOnes;
*/
gl->GetUIntegerv(LOCAL_GL_STENCIL_VALUE_MASK, &mStencilValueMaskFront);
gl->GetUIntegerv(LOCAL_GL_STENCIL_BACK_VALUE_MASK, &mStencilValueMaskBack);
gl->GetUIntegerv(LOCAL_GL_STENCIL_WRITEMASK, &mStencilWriteMaskFront);
gl->GetUIntegerv(LOCAL_GL_STENCIL_BACK_WRITEMASK, &mStencilWriteMaskBack);
AssertUintParamCorrect(gl, LOCAL_GL_STENCIL_VALUE_MASK,
mStencilValueMaskFront);
AssertUintParamCorrect(gl, LOCAL_GL_STENCIL_BACK_VALUE_MASK,
mStencilValueMaskBack);
AssertUintParamCorrect(gl, LOCAL_GL_STENCIL_WRITEMASK,
mStencilWriteMaskFront);
AssertUintParamCorrect(gl, LOCAL_GL_STENCIL_BACK_WRITEMASK,
mStencilWriteMaskBack);
mDitherEnabled = true;
mRasterizerDiscardEnabled = false;
mScissorTestEnabled = false;
mDepthTestEnabled = 0;
mDriverDepthTest = false;
mStencilTestEnabled = 0;
mDriverStencilTest = false;
mGenerateMipmapHint = LOCAL_GL_DONT_CARE;
// Bindings, etc.
mActiveTexture = 0;
mDefaultFB_DrawBuffer0 = LOCAL_GL_BACK;
mDefaultFB_ReadBuffer = LOCAL_GL_BACK;
mWebGLError = LOCAL_GL_NO_ERROR;
mBound2DTextures.Clear();
mBoundCubeMapTextures.Clear();
mBound3DTextures.Clear();
mBound2DArrayTextures.Clear();
mBoundSamplers.Clear();
mBoundArrayBuffer = nullptr;
mCurrentProgram = nullptr;
mBoundDrawFramebuffer = nullptr;
mBoundReadFramebuffer = nullptr;
mBoundRenderbuffer = nullptr;
gl->GetUIntegerv(LOCAL_GL_MAX_VERTEX_ATTRIBS, &mGLMaxVertexAttribs);
if (mGLMaxVertexAttribs < 8) {
const nsPrintfCString reason("GL_MAX_VERTEX_ATTRIBS: %d is < 8!",
mGLMaxVertexAttribs);
*out_failReason = {"FEATURE_FAILURE_WEBGL_V_ATRB", reason};
return false;
}
// Note: GL_MAX_TEXTURE_UNITS is fixed at 4 for most desktop hardware,
// even though the hardware supports much more. The
// GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS value is the accurate value.
mGLMaxCombinedTextureImageUnits =
gl->GetIntAs<GLuint>(LOCAL_GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS);
mGLMaxTextureUnits = mGLMaxCombinedTextureImageUnits;
if (mGLMaxCombinedTextureImageUnits < 8) {
const nsPrintfCString reason(
"GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS: %u is < 8!", mGLMaxTextureUnits);
*out_failReason = {"FEATURE_FAILURE_WEBGL_T_UNIT", reason};
return false;
}
mBound2DTextures.SetLength(mGLMaxTextureUnits);
mBoundCubeMapTextures.SetLength(mGLMaxTextureUnits);
mBound3DTextures.SetLength(mGLMaxTextureUnits);
mBound2DArrayTextures.SetLength(mGLMaxTextureUnits);
mBoundSamplers.SetLength(mGLMaxTextureUnits);
gl->fGetIntegerv(LOCAL_GL_MAX_VIEWPORT_DIMS, (GLint*)mGLMaxViewportDims);
////////////////
gl->fGetIntegerv(LOCAL_GL_MAX_TEXTURE_SIZE, (GLint*)&mGLMaxTextureSize);
gl->fGetIntegerv(LOCAL_GL_MAX_CUBE_MAP_TEXTURE_SIZE,
(GLint*)&mGLMaxCubeMapTextureSize);
gl->fGetIntegerv(LOCAL_GL_MAX_RENDERBUFFER_SIZE,
(GLint*)&mGLMaxRenderbufferSize);
if (!gl->GetPotentialInteger(LOCAL_GL_MAX_3D_TEXTURE_SIZE,
(GLint*)&mGLMax3DTextureSize))
mGLMax3DTextureSize = 0;
if (!gl->GetPotentialInteger(LOCAL_GL_MAX_ARRAY_TEXTURE_LAYERS,
(GLint*)&mGLMaxArrayTextureLayers))
mGLMaxArrayTextureLayers = 0;
(void)gl->GetPotentialInteger(LOCAL_GL_MAX_VIEWS_OVR,
(GLint*)&mGLMaxMultiviewViews);
gl->GetUIntegerv(LOCAL_GL_MAX_TEXTURE_IMAGE_UNITS,
&mGLMaxFragmentTextureImageUnits);
gl->GetUIntegerv(LOCAL_GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS,
&mGLMaxVertexTextureImageUnits);
////////////////
mGLMaxColorAttachments = 1;
mGLMaxDrawBuffers = 1;
if (IsWebGL2()) {
UpdateMaxDrawBuffers();
}
////////////////
if (gl->IsGLES()) {
mGLMaxFragmentUniformVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_FRAGMENT_UNIFORM_VECTORS);
mGLMaxVertexUniformVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VERTEX_UNIFORM_VECTORS);
if (gl->Version() >= 300) {
mGLMaxVertexOutputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VERTEX_OUTPUT_COMPONENTS) / 4;
mGLMaxFragmentInputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_FRAGMENT_INPUT_COMPONENTS) / 4;
} else {
mGLMaxFragmentInputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VARYING_VECTORS);
mGLMaxVertexOutputVectors = mGLMaxFragmentInputVectors;
}
} else {
mGLMaxFragmentUniformVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_FRAGMENT_UNIFORM_COMPONENTS) / 4;
mGLMaxVertexUniformVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VERTEX_UNIFORM_COMPONENTS) / 4;
if (gl->Version() >= 320) {
mGLMaxVertexOutputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VERTEX_OUTPUT_COMPONENTS) / 4;
mGLMaxFragmentInputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_FRAGMENT_INPUT_COMPONENTS) / 4;
} else {
// Same enum val as GL2's GL_MAX_VARYING_FLOATS.
mGLMaxFragmentInputVectors =
gl->GetIntAs<uint32_t>(LOCAL_GL_MAX_VARYING_COMPONENTS) / 4;
mGLMaxVertexOutputVectors = mGLMaxFragmentInputVectors;
}
}
////////////////
gl->fGetFloatv(LOCAL_GL_ALIASED_LINE_WIDTH_RANGE, mGLAliasedLineWidthRange);
const GLenum driverPName = gl->IsCoreProfile()
? LOCAL_GL_POINT_SIZE_RANGE
: LOCAL_GL_ALIASED_POINT_SIZE_RANGE;
gl->fGetFloatv(driverPName, mGLAliasedPointSizeRange);
////////////////
if (StaticPrefs::WebGLMinCapabilityMode()) {
bool ok = true;
ok &= RestrictCap(&mGLMaxVertexTextureImageUnits,
kMinMaxVertexTextureImageUnits);
ok &= RestrictCap(&mGLMaxFragmentTextureImageUnits,
kMinMaxFragmentTextureImageUnits);
ok &= RestrictCap(&mGLMaxCombinedTextureImageUnits,
kMinMaxCombinedTextureImageUnits);
ok &= RestrictCap(&mGLMaxVertexAttribs, kMinMaxVertexAttribs);
ok &= RestrictCap(&mGLMaxVertexUniformVectors, kMinMaxVertexUniformVectors);
ok &= RestrictCap(&mGLMaxFragmentUniformVectors,
kMinMaxFragmentUniformVectors);
ok &= RestrictCap(&mGLMaxVertexOutputVectors, kMinMaxVaryingVectors);
ok &= RestrictCap(&mGLMaxFragmentInputVectors, kMinMaxVaryingVectors);
ok &= RestrictCap(&mGLMaxColorAttachments, kMinMaxColorAttachments);
ok &= RestrictCap(&mGLMaxDrawBuffers, kMinMaxDrawBuffers);
ok &= RestrictCap(&mGLMaxTextureSize, kMinMaxTextureSize);
ok &= RestrictCap(&mGLMaxCubeMapTextureSize, kMinMaxCubeMapTextureSize);
ok &= RestrictCap(&mGLMax3DTextureSize, kMinMax3DTextureSize);
ok &= RestrictCap(&mGLMaxArrayTextureLayers, kMinMaxArrayTextureLayers);
ok &= RestrictCap(&mGLMaxRenderbufferSize, kMinMaxRenderbufferSize);
if (!ok) {
GenerateWarning("Unable to restrict WebGL limits to minimums.");
return false;
}
mDisableFragHighP = true;
} else if (ShouldResistFingerprinting()) {
bool ok = true;
ok &= RestrictCap(&mGLMaxTextureSize, kCommonMaxTextureSize);
ok &= RestrictCap(&mGLMaxCubeMapTextureSize, kCommonMaxCubeMapTextureSize);
ok &= RestrictCap(&mGLMaxRenderbufferSize, kCommonMaxRenderbufferSize);
ok &= RestrictCap(&mGLMaxVertexTextureImageUnits,
kCommonMaxVertexTextureImageUnits);
ok &= RestrictCap(&mGLMaxFragmentTextureImageUnits,
kCommonMaxFragmentTextureImageUnits);
ok &= RestrictCap(&mGLMaxCombinedTextureImageUnits,
kCommonMaxCombinedTextureImageUnits);
ok &= RestrictCap(&mGLMaxVertexAttribs, kCommonMaxVertexAttribs);
ok &= RestrictCap(&mGLMaxVertexUniformVectors,
kCommonMaxVertexUniformVectors);
ok &= RestrictCap(&mGLMaxFragmentUniformVectors,
kCommonMaxFragmentUniformVectors);
ok &= RestrictCap(&mGLMaxVertexOutputVectors, kCommonMaxVaryingVectors);
ok &= RestrictCap(&mGLMaxFragmentInputVectors, kCommonMaxVaryingVectors);
ok &= RestrictCap(&mGLAliasedLineWidthRange[0],
kCommonAliasedLineWidthRangeMin);
ok &= RestrictCap(&mGLAliasedLineWidthRange[1],
kCommonAliasedLineWidthRangeMax);
ok &= RestrictCap(&mGLAliasedPointSizeRange[0],
kCommonAliasedPointSizeRangeMin);
ok &= RestrictCap(&mGLAliasedPointSizeRange[1],
kCommonAliasedPointSizeRangeMax);
ok &= RestrictCap(&mGLMaxViewportDims[0], kCommonMaxViewportDims);
ok &= RestrictCap(&mGLMaxViewportDims[1], kCommonMaxViewportDims);
if (!ok) {
GenerateWarning(
"Unable to restrict WebGL limits in order to resist fingerprinting");
return false;
}
}
////////////////
if (gl->IsCompatibilityProfile()) {
gl->fEnable(LOCAL_GL_POINT_SPRITE);
}
if (!gl->IsGLES()) {
gl->fEnable(LOCAL_GL_PROGRAM_POINT_SIZE);
}
#ifdef XP_MACOSX
if (gl->WorkAroundDriverBugs() && gl->Vendor() == gl::GLVendor::ATI &&
!nsCocoaFeatures::IsAtLeastVersion(10, 9)) {
// The Mac ATI driver, in all known OSX version up to and including
// 10.8, renders points sprites upside-down. (Apple bug 11778921)
gl->fPointParameterf(LOCAL_GL_POINT_SPRITE_COORD_ORIGIN,
LOCAL_GL_LOWER_LEFT);
}
#endif
if (gl->IsSupported(gl::GLFeature::seamless_cube_map_opt_in)) {
gl->fEnable(LOCAL_GL_TEXTURE_CUBE_MAP_SEAMLESS);
}
// initialize shader translator
if (!sh::Initialize()) {
*out_failReason = {"FEATURE_FAILURE_WEBGL_GLSL",
"GLSL translator initialization failed!"};
return false;
}
// Mesa can only be detected with the GL_VERSION string, of the form
// "2.1 Mesa 7.11.0"
const char* versionStr = (const char*)(gl->fGetString(LOCAL_GL_VERSION));
mIsMesa = strstr(versionStr, "Mesa");
// Notice that the point of calling fGetError here is not only to check for
// errors, but also to reset the error flags so that a subsequent WebGL
// getError call will give the correct result.
error = gl->fGetError();
if (error != LOCAL_GL_NO_ERROR) {
const nsPrintfCString reason(
"GL error 0x%x occurred during WebGL context"
" initialization!",
error);
*out_failReason = {"FEATURE_FAILURE_WEBGL_GLERR_2", reason};
return false;
}
if (IsWebGL2() && !InitWebGL2(out_failReason)) {
// Todo: Bug 898404: Only allow WebGL2 on GL>=3.0 on desktop GL.
return false;
}
if (!gl->IsSupported(GLFeature::vertex_array_object)) {
*out_failReason = {"FEATURE_FAILURE_WEBGL_VAOS",
"Requires vertex_array_object."};
return false;
}
// OpenGL core profiles remove the default VAO object from version
// 4.0.0. We create a default VAO for all core profiles,
// regardless of version.
//
// GL Spec 4.0.0:
// (https://www.opengl.org/registry/doc/glspec40.core.20100311.pdf)
// in Section E.2.2 "Removed Features", pg 397: "[...] The default
// vertex array object (the name zero) is also deprecated. [...]"
mDefaultVertexArray = WebGLVertexArray::Create(this);
mDefaultVertexArray->BindVertexArray();
mDefaultVertexArray->mAttribs.SetLength(mGLMaxVertexAttribs);
mPixelStore_FlipY = false;
mPixelStore_PremultiplyAlpha = false;
mPixelStore_ColorspaceConversion = BROWSER_DEFAULT_WEBGL;
mPixelStore_RequireFastPath = false;
// GLES 3.0.4, p259:
mPixelStore_UnpackImageHeight = 0;
mPixelStore_UnpackSkipImages = 0;
mPixelStore_UnpackRowLength = 0;
mPixelStore_UnpackSkipRows = 0;
mPixelStore_UnpackSkipPixels = 0;
mPixelStore_UnpackAlignment = 4;
mPixelStore_PackRowLength = 0;
mPixelStore_PackSkipRows = 0;
mPixelStore_PackSkipPixels = 0;
mPixelStore_PackAlignment = 4;
mPrimRestartTypeBytes = 0;
mGenericVertexAttribTypes.assign(mGLMaxVertexAttribs,
webgl::AttribBaseType::Float);
mGenericVertexAttribTypeInvalidator.InvalidateCaches();
static const float kDefaultGenericVertexAttribData[4] = {0, 0, 0, 1};
memcpy(mGenericVertexAttrib0Data, kDefaultGenericVertexAttribData,
sizeof(mGenericVertexAttrib0Data));
mFakeVertexAttrib0BufferObject = 0;
mNeedsIndexValidation =
!gl->IsSupported(gl::GLFeature::robust_buffer_access_behavior);
switch (StaticPrefs::WebGLForceIndexValidation()) {
case -1:
mNeedsIndexValidation = false;
break;
case 1:
mNeedsIndexValidation = true;
break;
default:
MOZ_ASSERT(StaticPrefs::WebGLForceIndexValidation() == 0);
break;
}
return true;
}
bool WebGLContext::ValidateFramebufferTarget(GLenum target) const {
bool isValid = true;
switch (target) {
case LOCAL_GL_FRAMEBUFFER:
break;
case LOCAL_GL_DRAW_FRAMEBUFFER:
case LOCAL_GL_READ_FRAMEBUFFER:
isValid = IsWebGL2();
break;
default:
isValid = false;
break;
}
if (MOZ_LIKELY(isValid)) {
return true;
}
ErrorInvalidEnumArg("target", target);
return false;
}
} // namespace mozilla