anchor.diff:                              destRect.w <- int tileSize.X
                               destRect.h <- int tileSize.Y
                               let mutable rotationCenter = SDL.SDL_Point ()
  -                            rotationCenter.x <- int (tileSize.X * 0.5f)
  -                            rotationCenter.y <- int (tileSize.Y * 0.5f)
  +                            rotationCenter.x <- int <| tileSize.X * 0.5f
  +                            rotationCenter.y <- int <| tileSize.Y * 0.5f
                               let renderResult =
  -                                SDL.SDL_RenderCopyEx
  -                                    (renderer'.RenderContext,
  -                                        texture,
  -                                        ref sourceRect,
  -                                        ref destRect,
  -                                        double tileRotation * RadiansToDegrees,
  -                                        ref rotationCenter,
  -                                        SDL.SDL_RendererFlip.SDL_FLIP_NONE) // TODO: implement tile flip
  +                                SDL.SDL_RenderCopyEx (
  +                                    renderer'.RenderContext,
  +                                    texture,
  +                                    ref sourceRect,
  +                                    ref destRect,
  +                                    double tileRotation * RadiansToDegrees,
  +                                    ref rotationCenter,
  +                                    SDL.SDL_RendererFlip.SDL_FLIP_NONE) // TODO: implement tile flip
                               if renderResult <> 0 then debug <| "Rendering error - could not render texture for tile '" + str descriptor + "' due to '" + SDL.SDL_GetError () + ".")
                           tiles
                       renderer'
  
positive.code:     let private handleRenderMessages (renderMessages : RenderMessage rQueue) renderer =
          List.fold handleRenderMessage renderer (List.rev renderMessages)
  
      let private renderLayerableDescriptor renderer layerableDescriptor =
          match layerableDescriptor with
          | LayeredSpriteDescriptor lsd ->
  
negative.code:             | Some renderAsset ->
                  match renderAsset with
                  | TextureAsset texture ->
                      let mutable textureFormat = ref 0u
                      let mutable textureAccess = ref 0
                      let mutable textureSizeX = ref 0
                      let mutable textureSizeY = ref 0
                      ignore <| SDL.SDL_QueryTexture (texture, textureFormat, textureAccess, textureSizeX, textureSizeY)
                      let mutable sourceRect = SDL.SDL_Rect ()
                      sourceRect.x <- 0
                      sourceRect.y <- 0
                      sourceRect.w <- !textureSizeX
                      sourceRect.h <- !textureSizeY
                      let mutable destRect = SDL.SDL_Rect ()
                      destRect.x <- int spriteDescriptor.Position.X
                      destRect.y <- int spriteDescriptor.Position.Y
                      destRect.w <- int spriteDescriptor.Size.X
                      destRect.h <- int spriteDescriptor.Size.Y
                      let mutable rotationCenter = SDL.SDL_Point ()
                      rotationCenter.x <- int <| spriteDescriptor.Size.X * 0.5f
                      rotationCenter.y <- int <| spriteDescriptor.Size.Y * 0.5f
                      ignore <| SDL.SDL_SetTextureColorMod (texture, byte <| 255.0f * color.X, byte <| 255.0f * color.Y, byte <| 255.0f * color.Z)
                      ignore <| SDL.SDL_SetTextureAlphaMod (texture, byte <| 255.0f * color.W)
                      let renderResult =
                          SDL.SDL_RenderCopyEx (
                              renderer'.RenderContext,
                              texture,
                              ref sourceRect,
                              ref destRect,
                              double spriteDescriptor.Rotation * RadiansToDegrees,
                              ref rotationCenter,
                              SDL.SDL_RendererFlip.SDL_FLIP_NONE)
                      if renderResult <> 0 then debug <| "Rendering error - could not render texture for sprite '" + str spriteDescriptor + "' due to '" + SDL.SDL_GetError () + "."
                      renderer'
                  | _ ->
  