diff -r ff52fba70795 src/render/SDL_render.c
--- a/src/render/SDL_render.c	Tue May 07 16:52:39 2013 -0700
+++ b/src/render/SDL_render.c	Mon May 13 10:57:15 2013 -0400
@@ -119,9 +119,13 @@
 
                     SDL_GetWindowSize(window, &w, &h);
                     if (renderer->target) {
+                        renderer->viewport_backup.w = w;
+                        renderer->viewport_backup.h = h;
                         renderer->viewport_backup.x = (w - renderer->viewport_backup.w) / 2;
                         renderer->viewport_backup.y = (h - renderer->viewport_backup.h) / 2;
                     } else {
+                        renderer->viewport.w = w;
+                        renderer->viewport.h = h;
                         renderer->viewport.x = (w - renderer->viewport.w) / 2;
                         renderer->viewport.y = (h - renderer->viewport.h) / 2;
                         renderer->UpdateViewport(renderer);