+ // Measure the GPU time used for each actual phase during rendering.
+ // Note that this is only available if GL_ARB_timer_query
+ // (or, equivalently, OpenGL 3.3) is available. Also note that measurement
+ // will incur a performance cost, as we wait for the measurements to
+ // complete at the end of rendering.
+ void enable_phase_timing(bool enable);
+ void reset_phase_timing();
+ void print_phase_timing();