Header file for SDL 2D rendering functions.
This API supports the following features:
The primitives may be drawn in opaque, blended, or additive modes.
The texture images may be drawn in opaque, blended, or additive modes. They can have an additional color tint or alpha modulation applied to them, and may also be stretched with linear interpolation.
This API is designed to accelerate simple 2D operations. You may want more functionality such as polygons and particle effects and in that case you should use SDL's OpenGL/Direct3D support or one of the many good 3D engines.
These functions must be called from the main thread. See this bug for details: https://github.com/libsdl-org/SDL/issues/986