Fixed bug #4213 - update documentation to reflect SDL2 behavior of SDL_RenderGetLogicalSize

include/SDL_render.h

@@ -825,9 +825,11 @@ extern DECLSPEC int SDLCALL SDL_RenderSetLogicalSize(SDL_Renderer * renderer, in
 /**
  * Get device independent resolution for rendering.
  *
- * This may return 0 for `w` and `h` if the SDL_Renderer has never had its
- * logical size set by SDL_RenderSetLogicalSize() and never had a render
- * target set.
+ * When using the main rendering target (eg no target texture is set): this may return 0 for `w` and `h` if the SDL_Renderer has never had its
+ * logical size set by SDL_RenderSetLogicalSize(). Otherwise it returns the logical width and height.
+ *
+ * When using a target texture:
+ * Never return 0 for `w` and `h` at first. Then it returns the logical width and height that are set.
  *
  * \param renderer a rendering context
  * \param w an int to be filled with the width