Added SDL_GetRenderTarget() API function

Also fixed a bug with setting logical size for a render target.

include/SDL_render.h

@@ -413,10 +413,21 @@ extern DECLSPEC SDL_bool SDLCALL SDL_RenderTargetSupported(SDL_Renderer *rendere
  * \param texture The targeted texture, which must be created with the SDL_TEXTUREACCESS_TARGET flag, or NULL for the default render target
  *
  * \return 0 on success, or -1 on error
+ *
+ *  \sa SDL_GetRenderTarget()
  */
 extern DECLSPEC int SDLCALL SDL_SetRenderTarget(SDL_Renderer *renderer,
                                                 SDL_Texture *texture);
 
+/**
+ * \brief Get the current render target or NULL for the default render target.
+ *
+ * \return The current render target
+ *
+ *  \sa SDL_SetRenderTarget()
+ */
+extern DECLSPEC SDL_Texture * SDLCALL SDL_GetRenderTarget(SDL_Renderer *renderer);
+
 /**
  *  \brief Set device independent resolution for rendering
  *

src/render/SDL_render.c

@@ -952,6 +952,12 @@ SDL_SetRenderTarget(SDL_Renderer *renderer, SDL_Texture *texture)
     return 0;
 }
 
+SDL_Texture *
+SDL_GetRenderTarget(SDL_Renderer *renderer)
+{
+    return renderer->target;
+}
+
 static int
 UpdateLogicalSize(SDL_Renderer *renderer)
 {
@@ -961,7 +967,9 @@ UpdateLogicalSize(SDL_Renderer *renderer)
     float scale;
     SDL_Rect viewport;
 
-    if (renderer->window) {
+    if (renderer->target) {
+        SDL_QueryTexture(renderer->target, NULL, NULL, &w, &h);
+    } else if (renderer->window) {
         SDL_GetWindowSize(renderer->window, &w, &h);
     } else {
         /* FIXME */