On some system like MacBook Pro Intel with AMD card, asking for the default device will always return the AMD GPU.
This is not an issue for 99% of the case when the renderer context is here to provide the maximum performance level like for game.
However, for video application using GPU for 1 quad and 1 texture, using the discrete GPU for that lead to an important power consumption (4 to 8W), heat increase, and fan noise.
With this patch, I successfully amend ffplay to only use the integrated GPU (i.e. the Intel one), instead of the discrete GPU (i.e. the AMD one).