readPixels method

Pointer<SdlSurface> readPixels(
  1. Rectangle<double> rect
)

Read pixels from the current rendering target.

The returned surface contains pixels inside the desired area clipped to the current viewport, and should be freed with SDL_DestroySurface().

Note that this returns the actual pixels on the screen, so if you are using logical presentation you should use SDL_GetRenderLogicalPresentationRect() to get the area containing your content.

WARNING: This is a very slow operation, and should not be used frequently. If you're using this on the main rendering target, it should be called after rendering and before SDL_RenderPresent().

\param renderer the rendering context. \param rect an SDL_Rect structure representing the area to read, which will be clipped to the current viewport, or NULL for the entire viewport. \returns a new SDL_Surface on success or NULL on failure; call SDL_GetError() for more information.

\threadsafety This function should only be called on the main thread.

\since This function is available since SDL 3.2.0.

extern SDL_DECLSPEC SDL_Surface * SDLCALL SDL_RenderReadPixels(SDL_Renderer *renderer, const SDL_Rect *rect)

{@category render}

Implementation

Pointer<SdlSurface> readPixels(math.Rectangle<double> rect) {
  final rectPointer = rect.callocInt();
  final result = sdlRenderReadPixels(this, rectPointer);
  calloc.free(rectPointer);
  return result;
}