michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: 
michael@0: #include "gl/GrGLInterface.h"
michael@0: #include "gl/GrGLExtensions.h"
michael@0: #include "gl/GrGLUtil.h"
michael@0: 
michael@0: #include <stdio.h>
michael@0: 
michael@0: #if GR_GL_PER_GL_FUNC_CALLBACK
michael@0: namespace {
michael@0: void GrGLDefaultInterfaceCallback(const GrGLInterface*) {}
michael@0: }
michael@0: #endif
michael@0: 
michael@0: const GrGLInterface* GrGLInterfaceAddTestDebugMarker(const GrGLInterface* interface,
michael@0:                                                      GrGLInsertEventMarkerProc insertEventMarkerFn,
michael@0:                                                      GrGLPushGroupMarkerProc pushGroupMarkerFn,
michael@0:                                                      GrGLPopGroupMarkerProc popGroupMarkerFn) {
michael@0:     GrGLInterface* newInterface = GrGLInterface::NewClone(interface);
michael@0: 
michael@0:     if (!newInterface->fExtensions.has("GL_EXT_debug_marker")) {
michael@0:         newInterface->fExtensions.add("GL_EXT_debug_marker");
michael@0:     }
michael@0: 
michael@0:     newInterface->fFunctions.fInsertEventMarker = insertEventMarkerFn;
michael@0:     newInterface->fFunctions.fPushGroupMarker = pushGroupMarkerFn;
michael@0:     newInterface->fFunctions.fPopGroupMarker = popGroupMarkerFn;
michael@0: 
michael@0:     return newInterface;
michael@0: }
michael@0: 
michael@0: const GrGLInterface* GrGLInterfaceRemoveNVPR(const GrGLInterface* interface) {
michael@0:     GrGLInterface* newInterface = GrGLInterface::NewClone(interface);
michael@0: 
michael@0:     newInterface->fExtensions.remove("GL_NV_path_rendering");
michael@0: 
michael@0:     newInterface->fFunctions.fPathCommands = NULL;
michael@0:     newInterface->fFunctions.fPathCoords = NULL;
michael@0:     newInterface->fFunctions.fPathSubCommands = NULL;
michael@0:     newInterface->fFunctions.fPathSubCoords = NULL;
michael@0:     newInterface->fFunctions.fPathString = NULL;
michael@0:     newInterface->fFunctions.fPathGlyphs = NULL;
michael@0:     newInterface->fFunctions.fPathGlyphRange = NULL;
michael@0:     newInterface->fFunctions.fWeightPaths = NULL;
michael@0:     newInterface->fFunctions.fCopyPath = NULL;
michael@0:     newInterface->fFunctions.fInterpolatePaths = NULL;
michael@0:     newInterface->fFunctions.fTransformPath = NULL;
michael@0:     newInterface->fFunctions.fPathParameteriv = NULL;
michael@0:     newInterface->fFunctions.fPathParameteri = NULL;
michael@0:     newInterface->fFunctions.fPathParameterfv = NULL;
michael@0:     newInterface->fFunctions.fPathParameterf = NULL;
michael@0:     newInterface->fFunctions.fPathDashArray = NULL;
michael@0:     newInterface->fFunctions.fGenPaths = NULL;
michael@0:     newInterface->fFunctions.fDeletePaths = NULL;
michael@0:     newInterface->fFunctions.fIsPath = NULL;
michael@0:     newInterface->fFunctions.fPathStencilFunc = NULL;
michael@0:     newInterface->fFunctions.fPathStencilDepthOffset = NULL;
michael@0:     newInterface->fFunctions.fStencilFillPath = NULL;
michael@0:     newInterface->fFunctions.fStencilStrokePath = NULL;
michael@0:     newInterface->fFunctions.fStencilFillPathInstanced = NULL;
michael@0:     newInterface->fFunctions.fStencilStrokePathInstanced = NULL;
michael@0:     newInterface->fFunctions.fPathCoverDepthFunc = NULL;
michael@0:     newInterface->fFunctions.fPathColorGen = NULL;
michael@0:     newInterface->fFunctions.fPathTexGen = NULL;
michael@0:     newInterface->fFunctions.fPathFogGen = NULL;
michael@0:     newInterface->fFunctions.fCoverFillPath = NULL;
michael@0:     newInterface->fFunctions.fCoverStrokePath = NULL;
michael@0:     newInterface->fFunctions.fCoverFillPathInstanced = NULL;
michael@0:     newInterface->fFunctions.fCoverStrokePathInstanced = NULL;
michael@0:     newInterface->fFunctions.fGetPathParameteriv = NULL;
michael@0:     newInterface->fFunctions.fGetPathParameterfv = NULL;
michael@0:     newInterface->fFunctions.fGetPathCommands = NULL;
michael@0:     newInterface->fFunctions.fGetPathCoords = NULL;
michael@0:     newInterface->fFunctions.fGetPathDashArray = NULL;
michael@0:     newInterface->fFunctions.fGetPathMetrics = NULL;
michael@0:     newInterface->fFunctions.fGetPathMetricRange = NULL;
michael@0:     newInterface->fFunctions.fGetPathSpacing = NULL;
michael@0:     newInterface->fFunctions.fGetPathColorGeniv = NULL;
michael@0:     newInterface->fFunctions.fGetPathColorGenfv = NULL;
michael@0:     newInterface->fFunctions.fGetPathTexGeniv = NULL;
michael@0:     newInterface->fFunctions.fGetPathTexGenfv = NULL;
michael@0:     newInterface->fFunctions.fIsPointInFillPath = NULL;
michael@0:     newInterface->fFunctions.fIsPointInStrokePath = NULL;
michael@0:     newInterface->fFunctions.fGetPathLength = NULL;
michael@0:     newInterface->fFunctions.fPointAlongPath = NULL;
michael@0: 
michael@0:     return newInterface;
michael@0: }
michael@0: 
michael@0: GrGLInterface::GrGLInterface() {
michael@0:     fStandard = kNone_GrGLStandard;
michael@0: 
michael@0: #if GR_GL_PER_GL_FUNC_CALLBACK
michael@0:     fCallback = GrGLDefaultInterfaceCallback;
michael@0:     fCallbackData = 0;
michael@0: #endif
michael@0: }
michael@0: 
michael@0: GrGLInterface* GrGLInterface::NewClone(const GrGLInterface* interface) {
michael@0:     SkASSERT(NULL != interface);
michael@0: 
michael@0:     GrGLInterface* clone = SkNEW(GrGLInterface);
michael@0:     clone->fStandard = interface->fStandard;
michael@0:     clone->fExtensions = interface->fExtensions;
michael@0:     clone->fFunctions = interface->fFunctions;
michael@0: #if GR_GL_PER_GL_FUNC_CALLBACK
michael@0:     clone->fCallback = interface->fCallback;
michael@0:     clone->fCallbackData = interface->fCallbackData;
michael@0: #endif
michael@0:     return clone;
michael@0: }
michael@0: 
michael@0: bool GrGLInterface::validate() const {
michael@0: 
michael@0:     if (kNone_GrGLStandard == fStandard) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     if (!fExtensions.isInitialized()) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     // functions that are always required
michael@0:     if (NULL == fFunctions.fActiveTexture ||
michael@0:         NULL == fFunctions.fAttachShader ||
michael@0:         NULL == fFunctions.fBindAttribLocation ||
michael@0:         NULL == fFunctions.fBindBuffer ||
michael@0:         NULL == fFunctions.fBindTexture ||
michael@0:         NULL == fFunctions.fBlendFunc ||
michael@0:         NULL == fFunctions.fBlendColor ||      // -> GL >= 1.4, ES >= 2.0 or extension
michael@0:         NULL == fFunctions.fBufferData ||
michael@0:         NULL == fFunctions.fBufferSubData ||
michael@0:         NULL == fFunctions.fClear ||
michael@0:         NULL == fFunctions.fClearColor ||
michael@0:         NULL == fFunctions.fClearStencil ||
michael@0:         NULL == fFunctions.fColorMask ||
michael@0:         NULL == fFunctions.fCompileShader ||
michael@0:         NULL == fFunctions.fCopyTexSubImage2D ||
michael@0:         NULL == fFunctions.fCreateProgram ||
michael@0:         NULL == fFunctions.fCreateShader ||
michael@0:         NULL == fFunctions.fCullFace ||
michael@0:         NULL == fFunctions.fDeleteBuffers ||
michael@0:         NULL == fFunctions.fDeleteProgram ||
michael@0:         NULL == fFunctions.fDeleteShader ||
michael@0:         NULL == fFunctions.fDeleteTextures ||
michael@0:         NULL == fFunctions.fDepthMask ||
michael@0:         NULL == fFunctions.fDisable ||
michael@0:         NULL == fFunctions.fDisableVertexAttribArray ||
michael@0:         NULL == fFunctions.fDrawArrays ||
michael@0:         NULL == fFunctions.fDrawElements ||
michael@0:         NULL == fFunctions.fEnable ||
michael@0:         NULL == fFunctions.fEnableVertexAttribArray ||
michael@0:         NULL == fFunctions.fFrontFace ||
michael@0:         NULL == fFunctions.fGenBuffers ||
michael@0:         NULL == fFunctions.fGenTextures ||
michael@0:         NULL == fFunctions.fGetBufferParameteriv ||
michael@0:         NULL == fFunctions.fGenerateMipmap ||
michael@0:         NULL == fFunctions.fGetError ||
michael@0:         NULL == fFunctions.fGetIntegerv ||
michael@0:         NULL == fFunctions.fGetProgramInfoLog ||
michael@0:         NULL == fFunctions.fGetProgramiv ||
michael@0:         NULL == fFunctions.fGetShaderInfoLog ||
michael@0:         NULL == fFunctions.fGetShaderiv ||
michael@0:         NULL == fFunctions.fGetString ||
michael@0:         NULL == fFunctions.fGetUniformLocation ||
michael@0:         NULL == fFunctions.fLinkProgram ||
michael@0:         NULL == fFunctions.fLineWidth ||
michael@0:         NULL == fFunctions.fPixelStorei ||
michael@0:         NULL == fFunctions.fReadPixels ||
michael@0:         NULL == fFunctions.fScissor ||
michael@0:         NULL == fFunctions.fShaderSource ||
michael@0:         NULL == fFunctions.fStencilFunc ||
michael@0:         NULL == fFunctions.fStencilMask ||
michael@0:         NULL == fFunctions.fStencilOp ||
michael@0:         NULL == fFunctions.fTexImage2D ||
michael@0:         NULL == fFunctions.fTexParameteri ||
michael@0:         NULL == fFunctions.fTexParameteriv ||
michael@0:         NULL == fFunctions.fTexSubImage2D ||
michael@0:         NULL == fFunctions.fUniform1f ||
michael@0:         NULL == fFunctions.fUniform1i ||
michael@0:         NULL == fFunctions.fUniform1fv ||
michael@0:         NULL == fFunctions.fUniform1iv ||
michael@0:         NULL == fFunctions.fUniform2f ||
michael@0:         NULL == fFunctions.fUniform2i ||
michael@0:         NULL == fFunctions.fUniform2fv ||
michael@0:         NULL == fFunctions.fUniform2iv ||
michael@0:         NULL == fFunctions.fUniform3f ||
michael@0:         NULL == fFunctions.fUniform3i ||
michael@0:         NULL == fFunctions.fUniform3fv ||
michael@0:         NULL == fFunctions.fUniform3iv ||
michael@0:         NULL == fFunctions.fUniform4f ||
michael@0:         NULL == fFunctions.fUniform4i ||
michael@0:         NULL == fFunctions.fUniform4fv ||
michael@0:         NULL == fFunctions.fUniform4iv ||
michael@0:         NULL == fFunctions.fUniformMatrix2fv ||
michael@0:         NULL == fFunctions.fUniformMatrix3fv ||
michael@0:         NULL == fFunctions.fUniformMatrix4fv ||
michael@0:         NULL == fFunctions.fUseProgram ||
michael@0:         NULL == fFunctions.fVertexAttrib4fv ||
michael@0:         NULL == fFunctions.fVertexAttribPointer ||
michael@0:         NULL == fFunctions.fViewport ||
michael@0:         NULL == fFunctions.fBindFramebuffer ||
michael@0:         NULL == fFunctions.fBindRenderbuffer ||
michael@0:         NULL == fFunctions.fCheckFramebufferStatus ||
michael@0:         NULL == fFunctions.fDeleteFramebuffers ||
michael@0:         NULL == fFunctions.fDeleteRenderbuffers ||
michael@0:         NULL == fFunctions.fFinish ||
michael@0:         NULL == fFunctions.fFlush ||
michael@0:         NULL == fFunctions.fFramebufferRenderbuffer ||
michael@0:         NULL == fFunctions.fFramebufferTexture2D ||
michael@0:         NULL == fFunctions.fGetFramebufferAttachmentParameteriv ||
michael@0:         NULL == fFunctions.fGetRenderbufferParameteriv ||
michael@0:         NULL == fFunctions.fGenFramebuffers ||
michael@0:         NULL == fFunctions.fGenRenderbuffers ||
michael@0:         NULL == fFunctions.fRenderbufferStorage) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     GrGLVersion glVer = GrGLGetVersion(this);
michael@0: 
michael@0:     bool isCoreProfile = false;
michael@0:     if (kGL_GrGLStandard == fStandard && glVer >= GR_GL_VER(3,2)) {
michael@0:         GrGLint profileMask;
michael@0:         GR_GL_GetIntegerv(this, GR_GL_CONTEXT_PROFILE_MASK, &profileMask);
michael@0:         isCoreProfile = SkToBool(profileMask & GR_GL_CONTEXT_CORE_PROFILE_BIT);
michael@0:     }
michael@0: 
michael@0:     // Now check that baseline ES/Desktop fns not covered above are present
michael@0:     // and that we have fn pointers for any advertised fExtensions that we will
michael@0:     // try to use.
michael@0: 
michael@0:     // these functions are part of ES2, we assume they are available
michael@0:     // On the desktop we assume they are available if the extension
michael@0:     // is present or GL version is high enough.
michael@0:     if (kGLES_GrGLStandard == fStandard) {
michael@0:         if (NULL == fFunctions.fStencilFuncSeparate ||
michael@0:             NULL == fFunctions.fStencilMaskSeparate ||
michael@0:             NULL == fFunctions.fStencilOpSeparate) {
michael@0:             return false;
michael@0:         }
michael@0:     } else if (kGL_GrGLStandard == fStandard) {
michael@0: 
michael@0:         if (glVer >= GR_GL_VER(2,0)) {
michael@0:             if (NULL == fFunctions.fStencilFuncSeparate ||
michael@0:                 NULL == fFunctions.fStencilMaskSeparate ||
michael@0:                 NULL == fFunctions.fStencilOpSeparate) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (glVer >= GR_GL_VER(3,0) && NULL == fFunctions.fBindFragDataLocation) {
michael@0:             return false;
michael@0:         }
michael@0:         if (glVer >= GR_GL_VER(2,0) || fExtensions.has("GL_ARB_draw_buffers")) {
michael@0:             if (NULL == fFunctions.fDrawBuffers) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0: 
michael@0:         if (glVer >= GR_GL_VER(1,5) || fExtensions.has("GL_ARB_occlusion_query")) {
michael@0:             if (NULL == fFunctions.fGenQueries ||
michael@0:                 NULL == fFunctions.fDeleteQueries ||
michael@0:                 NULL == fFunctions.fBeginQuery ||
michael@0:                 NULL == fFunctions.fEndQuery ||
michael@0:                 NULL == fFunctions.fGetQueryiv ||
michael@0:                 NULL == fFunctions.fGetQueryObjectiv ||
michael@0:                 NULL == fFunctions.fGetQueryObjectuiv) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (glVer >= GR_GL_VER(3,3) ||
michael@0:             fExtensions.has("GL_ARB_timer_query") ||
michael@0:             fExtensions.has("GL_EXT_timer_query")) {
michael@0:             if (NULL == fFunctions.fGetQueryObjecti64v ||
michael@0:                 NULL == fFunctions.fGetQueryObjectui64v) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (glVer >= GR_GL_VER(3,3) || fExtensions.has("GL_ARB_timer_query")) {
michael@0:             if (NULL == fFunctions.fQueryCounter) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (!isCoreProfile) {
michael@0:             if (NULL == fFunctions.fLoadIdentity ||
michael@0:                 NULL == fFunctions.fLoadMatrixf ||
michael@0:                 NULL == fFunctions.fMatrixMode ||
michael@0:                 NULL == fFunctions.fTexGenfv ||
michael@0:                 NULL == fFunctions.fTexGeni) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (fExtensions.has("GL_NV_path_rendering")) {
michael@0:             if (NULL == fFunctions.fPathCommands ||
michael@0:                 NULL == fFunctions.fPathCoords ||
michael@0:                 NULL == fFunctions.fPathSubCommands ||
michael@0:                 NULL == fFunctions.fPathSubCoords ||
michael@0:                 NULL == fFunctions.fPathString ||
michael@0:                 NULL == fFunctions.fPathGlyphs ||
michael@0:                 NULL == fFunctions.fPathGlyphRange ||
michael@0:                 NULL == fFunctions.fWeightPaths ||
michael@0:                 NULL == fFunctions.fCopyPath ||
michael@0:                 NULL == fFunctions.fInterpolatePaths ||
michael@0:                 NULL == fFunctions.fTransformPath ||
michael@0:                 NULL == fFunctions.fPathParameteriv ||
michael@0:                 NULL == fFunctions.fPathParameteri ||
michael@0:                 NULL == fFunctions.fPathParameterfv ||
michael@0:                 NULL == fFunctions.fPathParameterf ||
michael@0:                 NULL == fFunctions.fPathDashArray ||
michael@0:                 NULL == fFunctions.fGenPaths ||
michael@0:                 NULL == fFunctions.fDeletePaths ||
michael@0:                 NULL == fFunctions.fIsPath ||
michael@0:                 NULL == fFunctions.fPathStencilFunc ||
michael@0:                 NULL == fFunctions.fPathStencilDepthOffset ||
michael@0:                 NULL == fFunctions.fStencilFillPath ||
michael@0:                 NULL == fFunctions.fStencilStrokePath ||
michael@0:                 NULL == fFunctions.fStencilFillPathInstanced ||
michael@0:                 NULL == fFunctions.fStencilStrokePathInstanced ||
michael@0:                 NULL == fFunctions.fPathCoverDepthFunc ||
michael@0:                 NULL == fFunctions.fPathColorGen ||
michael@0:                 NULL == fFunctions.fPathTexGen ||
michael@0:                 NULL == fFunctions.fPathFogGen ||
michael@0:                 NULL == fFunctions.fCoverFillPath ||
michael@0:                 NULL == fFunctions.fCoverStrokePath ||
michael@0:                 NULL == fFunctions.fCoverFillPathInstanced ||
michael@0:                 NULL == fFunctions.fCoverStrokePathInstanced ||
michael@0:                 NULL == fFunctions.fGetPathParameteriv ||
michael@0:                 NULL == fFunctions.fGetPathParameterfv ||
michael@0:                 NULL == fFunctions.fGetPathCommands ||
michael@0:                 NULL == fFunctions.fGetPathCoords ||
michael@0:                 NULL == fFunctions.fGetPathDashArray ||
michael@0:                 NULL == fFunctions.fGetPathMetrics ||
michael@0:                 NULL == fFunctions.fGetPathMetricRange ||
michael@0:                 NULL == fFunctions.fGetPathSpacing ||
michael@0:                 NULL == fFunctions.fGetPathColorGeniv ||
michael@0:                 NULL == fFunctions.fGetPathColorGenfv ||
michael@0:                 NULL == fFunctions.fGetPathTexGeniv ||
michael@0:                 NULL == fFunctions.fGetPathTexGenfv ||
michael@0:                 NULL == fFunctions.fIsPointInFillPath ||
michael@0:                 NULL == fFunctions.fIsPointInStrokePath ||
michael@0:                 NULL == fFunctions.fGetPathLength ||
michael@0:                 NULL == fFunctions.fPointAlongPath) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // optional function on desktop before 1.3
michael@0:     if (kGL_GrGLStandard != fStandard ||
michael@0:         (glVer >= GR_GL_VER(1,3)) ||
michael@0:         fExtensions.has("GL_ARB_texture_compression")) {
michael@0:         if (NULL == fFunctions.fCompressedTexImage2D) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // part of desktop GL, but not ES
michael@0:     if (kGL_GrGLStandard == fStandard &&
michael@0:         (NULL == fFunctions.fGetTexLevelParameteriv ||
michael@0:          NULL == fFunctions.fDrawBuffer ||
michael@0:          NULL == fFunctions.fReadBuffer)) {
michael@0:         return false;
michael@0:     }
michael@0: 
michael@0:     // GL_EXT_texture_storage is part of desktop 4.2
michael@0:     // There is a desktop ARB extension and an ES+desktop EXT extension
michael@0:     if (kGL_GrGLStandard == fStandard) {
michael@0:         if (glVer >= GR_GL_VER(4,2) ||
michael@0:             fExtensions.has("GL_ARB_texture_storage") ||
michael@0:             fExtensions.has("GL_EXT_texture_storage")) {
michael@0:             if (NULL == fFunctions.fTexStorage2D) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     } else if (glVer >= GR_GL_VER(3,0) || fExtensions.has("GL_EXT_texture_storage")) {
michael@0:         if (NULL == fFunctions.fTexStorage2D) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (fExtensions.has("GL_EXT_discard_framebuffer")) {
michael@0: // FIXME: Remove this once Chromium is updated to provide this function
michael@0: #if 0
michael@0:         if (NULL == fFunctions.fDiscardFramebuffer) {
michael@0:             return false;
michael@0:         }
michael@0: #endif
michael@0:     }
michael@0: 
michael@0:     // FBO MSAA
michael@0:     if (kGL_GrGLStandard == fStandard) {
michael@0:         // GL 3.0 and the ARB extension have multisample + blit
michael@0:         if (glVer >= GR_GL_VER(3,0) || fExtensions.has("GL_ARB_framebuffer_object")) {
michael@0:             if (NULL == fFunctions.fRenderbufferStorageMultisample ||
michael@0:                 NULL == fFunctions.fBlitFramebuffer) {
michael@0:                 return false;
michael@0:             }
michael@0:         } else {
michael@0:             if (fExtensions.has("GL_EXT_framebuffer_blit") &&
michael@0:                 NULL == fFunctions.fBlitFramebuffer) {
michael@0:                 return false;
michael@0:             }
michael@0:             if (fExtensions.has("GL_EXT_framebuffer_multisample") &&
michael@0:                 NULL == fFunctions.fRenderbufferStorageMultisample) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     } else {
michael@0:         if (glVer >= GR_GL_VER(3,0) || fExtensions.has("GL_CHROMIUM_framebuffer_multisample")) {
michael@0:             if (NULL == fFunctions.fRenderbufferStorageMultisample ||
michael@0:                 NULL == fFunctions.fBlitFramebuffer) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (fExtensions.has("GL_APPLE_framebuffer_multisample")) {
michael@0:             if (NULL == fFunctions.fRenderbufferStorageMultisampleES2APPLE ||
michael@0:                 NULL == fFunctions.fResolveMultisampleFramebuffer) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:         if (fExtensions.has("GL_IMG_multisampled_render_to_texture") ||
michael@0:             fExtensions.has("GL_EXT_multisampled_render_to_texture")) {
michael@0:             if (NULL == fFunctions.fRenderbufferStorageMultisampleES2EXT ||
michael@0:                 NULL == fFunctions.fFramebufferTexture2DMultisample) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // On ES buffer mapping is an extension. On Desktop
michael@0:     // buffer mapping was part of original VBO extension
michael@0:     // which we require.
michael@0:     if (kGL_GrGLStandard == fStandard || fExtensions.has("GL_OES_mapbuffer")) {
michael@0:         if (NULL == fFunctions.fMapBuffer ||
michael@0:             NULL == fFunctions.fUnmapBuffer) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // Dual source blending
michael@0:     if (kGL_GrGLStandard == fStandard &&
michael@0:         (glVer >= GR_GL_VER(3,3) || fExtensions.has("GL_ARB_blend_func_extended"))) {
michael@0:         if (NULL == fFunctions.fBindFragDataLocationIndexed) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     // glGetStringi was added in version 3.0 of both desktop and ES.
michael@0:     if (glVer >= GR_GL_VER(3, 0)) {
michael@0:         if (NULL == fFunctions.fGetStringi) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     if (kGL_GrGLStandard == fStandard) {
michael@0:         if (glVer >= GR_GL_VER(3, 0) || fExtensions.has("GL_ARB_vertex_array_object")) {
michael@0:             if (NULL == fFunctions.fBindVertexArray ||
michael@0:                 NULL == fFunctions.fDeleteVertexArrays ||
michael@0:                 NULL == fFunctions.fGenVertexArrays) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     } else {
michael@0:         if (glVer >= GR_GL_VER(3,0) || fExtensions.has("GL_OES_vertex_array_object")) {
michael@0:             if (NULL == fFunctions.fBindVertexArray ||
michael@0:                 NULL == fFunctions.fDeleteVertexArrays ||
michael@0:                 NULL == fFunctions.fGenVertexArrays) {
michael@0:                 return false;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0: #if 0
michael@0:     if (fExtensions.has("GL_EXT_debug_marker")) {
michael@0:         if (NULL == fFunctions.fInsertEventMarker ||
michael@0:             NULL == fFunctions.fPushGroupMarker ||
michael@0:             NULL == fFunctions.fPopGroupMarker) {
michael@0:             return false;
michael@0:         }
michael@0:     }
michael@0: #endif
michael@0:     return true;
michael@0: }