Wraps SDL_RenderSetViewport which sets or removes the viewport dsdl2.Rect of the dsdl2.Renderer
dsdl2.Rect to set as the rectangle viewport; null to remove the rectangle viewport
dsdl2.SDLException if failed to set the renderer's viewport
See Implementation
Wraps SDL_RenderSetViewport which sets or removes the viewport dsdl2.Rect of the dsdl2.Renderer