SDL_StretchSurfaceBlit — Perform a stretch blit between two surfaces of the same format.
The SDL_StretchSurfaceBlit function is not safe to call from multiple threads!
The SDL_StretchSurfaceBlit function will stretch a srcrect smoothly to the full area of
the dst surface. If no srcrect is given then the full area of the
src surface is stretched smoothly to the full dst surface. The
dstrect is ignored always.
Remember that this is the inverse meaning, the main SDL lib will ignore the srcrect and only watch for the dstrect if any.