A variable controlling whether the 2D render API is compatible or efficient.
Defined in SDL_hints.h
#define SDL_HINT_RENDER_BATCHING "SDL_RENDER_BATCHING"This variable can be set to the following values:
Up to SDL 2.0.9, the render API would draw immediately when requested. Now it batches up draw requests and sends them all to the GPU only when forced to (during SDL_RenderPresent, when changing render targets, by updating a texture that the batch needs, etc). This is significantly more efficient, but it can cause problems for apps that expect to render on top of the render API's output. As such, SDL will disable batching if a specific render backend is requested (since this might indicate that the app is planning to use the underlying graphics API directly). This hint can be used to explicitly request batching in this instance. It is a contract that you will either never use the underlying graphics API directly, or if you do, you will call SDL_RenderFlush() before you do so any current batch goes to the GPU before your work begins. Not following this contract will result in undefined behavior.