1 // Copyright 2019 The Dawn Authors 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #include "dawn_native/opengl/OpenGLFunctions.h" 16 17 #include <cctype> 18 #include <tuple> 19 20 namespace dawn_native { namespace opengl { 21 Initialize(GetProcAddress getProc)22 MaybeError OpenGLFunctions::Initialize(GetProcAddress getProc) { 23 PFNGLGETSTRINGPROC getString = reinterpret_cast<PFNGLGETSTRINGPROC>(getProc("glGetString")); 24 if (getString == nullptr) { 25 return DAWN_INTERNAL_ERROR("Couldn't load glGetString"); 26 } 27 28 std::string version = reinterpret_cast<const char*>(getString(GL_VERSION)); 29 30 if (version.find("OpenGL ES") != std::string::npos) { 31 // ES spec states that the GL_VERSION string will be in the following format: 32 // "OpenGL ES N.M vendor-specific information" 33 mStandard = Standard::ES; 34 mMajorVersion = version[10] - '0'; 35 mMinorVersion = version[12] - '0'; 36 37 // The minor version shouldn't get to two digits. 38 ASSERT(version.size() <= 13 || !isdigit(version[13])); 39 40 DAWN_TRY(LoadOpenGLESProcs(getProc, mMajorVersion, mMinorVersion)); 41 } else { 42 // OpenGL spec states the GL_VERSION string will be in the following format: 43 // <version number><space><vendor-specific information> 44 // The version number is either of the form major number.minor number or major 45 // number.minor number.release number, where the numbers all have one or more 46 // digits 47 mStandard = Standard::Desktop; 48 mMajorVersion = version[0] - '0'; 49 mMinorVersion = version[2] - '0'; 50 51 // The minor version shouldn't get to two digits. 52 ASSERT(version.size() <= 3 || !isdigit(version[3])); 53 54 DAWN_TRY(LoadDesktopGLProcs(getProc, mMajorVersion, mMinorVersion)); 55 } 56 57 InitializeSupportedGLExtensions(); 58 59 return {}; 60 } 61 InitializeSupportedGLExtensions()62 void OpenGLFunctions::InitializeSupportedGLExtensions() { 63 int32_t numExtensions; 64 GetIntegerv(GL_NUM_EXTENSIONS, &numExtensions); 65 66 for (int32_t i = 0; i < numExtensions; ++i) { 67 const char* extensionName = reinterpret_cast<const char*>(GetStringi(GL_EXTENSIONS, i)); 68 mSupportedGLExtensionsSet.insert(extensionName); 69 } 70 } 71 IsGLExtensionSupported(const char * extension) const72 bool OpenGLFunctions::IsGLExtensionSupported(const char* extension) const { 73 ASSERT(extension != nullptr); 74 return mSupportedGLExtensionsSet.count(extension) != 0; 75 } 76 IsAtLeastGL(uint32_t majorVersion,uint32_t minorVersion) const77 bool OpenGLFunctions::IsAtLeastGL(uint32_t majorVersion, uint32_t minorVersion) const { 78 return mStandard == Standard::Desktop && 79 std::tie(mMajorVersion, mMinorVersion) >= std::tie(majorVersion, minorVersion); 80 } 81 IsAtLeastGLES(uint32_t majorVersion,uint32_t minorVersion) const82 bool OpenGLFunctions::IsAtLeastGLES(uint32_t majorVersion, uint32_t minorVersion) const { 83 return mStandard == Standard::ES && 84 std::tie(mMajorVersion, mMinorVersion) >= std::tie(majorVersion, minorVersion); 85 } 86 87 }} // namespace dawn_native::opengl 88