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#ifndef ForceDiscreteGPUHelperCGL_h_
#define ForceDiscreteGPUHelperCGL_h_

#include <OpenGL/OpenGL.h>

/** This RAII helper guarantees that we're on the discrete GPU during its lifetime.
 * 
 * As long as any ForceDiscreteGPUHelperCGL object is alive, we're on the discrete GPU.
 */
class ForceDiscreteGPUHelperCGL
{
    CGLPixelFormatObj mPixelFormatObj;

public:
    ForceDiscreteGPUHelperCGL()
    {
        // the code in this function is taken from Chromium, src/ui/gfx/gl/gl_context_cgl.cc, r122013
        // BSD-style license, (c) The Chromium Authors
        CGLPixelFormatAttribute attribs[1];
        attribs[0] = static_cast<CGLPixelFormatAttribute>(0);
        GLint num_pixel_formats = 0;
        CGLChoosePixelFormat(attribs, &mPixelFormatObj, &num_pixel_formats);
    }

    ~ForceDiscreteGPUHelperCGL()
    {
        CGLReleasePixelFormat(mPixelFormatObj);
    }
};

#endif // ForceDiscreteGPUHelperCGL_h_
