ForceDiscreteGPUHelperCGL.h (1196B)
1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*- 2 * This Source Code Form is subject to the terms of the Mozilla Public 3 * License, v. 2.0. If a copy of the MPL was not distributed with this 4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 5 6 #ifndef ForceDiscreteGPUHelperCGL_h_ 7 #define ForceDiscreteGPUHelperCGL_h_ 8 9 #include <OpenGL/OpenGL.h> 10 11 /** This RAII helper guarantees that we're on the discrete GPU during its 12 * lifetime. 13 * 14 * As long as any ForceDiscreteGPUHelperCGL object is alive, we're on the 15 * discrete GPU. 16 */ 17 class ForceDiscreteGPUHelperCGL { 18 CGLPixelFormatObj mPixelFormatObj; 19 20 public: 21 ForceDiscreteGPUHelperCGL() : mPixelFormatObj(nullptr) { 22 // the code in this function is taken from Chromium, 23 // src/ui/gfx/gl/gl_context_cgl.cc, r122013 24 // BSD-style license, (c) The Chromium Authors 25 CGLPixelFormatAttribute attribs[1]; 26 attribs[0] = static_cast<CGLPixelFormatAttribute>(0); 27 GLint num_pixel_formats = 0; 28 CGLChoosePixelFormat(attribs, &mPixelFormatObj, &num_pixel_formats); 29 } 30 31 ~ForceDiscreteGPUHelperCGL() { CGLReleasePixelFormat(mPixelFormatObj); } 32 }; 33 34 #endif // ForceDiscreteGPUHelperCGL_h_