3 files changed, 10 insertions, 12 deletions
diff --git a/source/blender/windowmanager/intern/wm_draw.c b/source/blender/windowmanager/intern/wm_draw.c
index 6c9bba0791c..a5dfc9893a5 100644
--- a/source/blender/windowmanager/intern/wm_draw.c
+++ b/source/blender/windowmanager/intern/wm_draw.c
@@ -826,13 +826,11 @@ static void wm_draw_window(bContext *C, wmWindow *win)
   }
   else if (win->stereo3d_format->display_mode == S3D_DISPLAY_PAGEFLIP) {
     /* For pageflip we simply draw to both back buffers. */
-    GPU_backbuffer_bind(GPU_BACKBUFFER_LEFT);
-    wm_draw_window_onscreen(C, win, 0);
-
     GPU_backbuffer_bind(GPU_BACKBUFFER_RIGHT);
     wm_draw_window_onscreen(C, win, 1);
 
-    GPU_backbuffer_bind(GPU_BACKBUFFER);
+    GPU_backbuffer_bind(GPU_BACKBUFFER_LEFT);
+    wm_draw_window_onscreen(C, win, 0);
   }
   else if (ELEM(win->stereo3d_format->display_mode, S3D_DISPLAY_ANAGLYPH, S3D_DISPLAY_INTERLACE)) {
     /* For anaglyph and interlace, we draw individual regions with
diff --git a/source/blender/windowmanager/intern/wm_surface.c b/source/blender/windowmanager/intern/wm_surface.c
index 9948434d340..e8cb5d9cd7d 100644
--- a/source/blender/windowmanager/intern/wm_surface.c
+++ b/source/blender/windowmanager/intern/wm_surface.c
@@ -84,7 +84,7 @@ void wm_surface_set_drawable(wmSurface *surface, bool activate)
 
 void wm_surface_make_drawable(wmSurface *surface)
 {
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
 
   if (surface != g_drawable) {
     wm_surface_clear_drawable();
@@ -95,7 +95,7 @@ void wm_surface_make_drawable(wmSurface *surface)
 void wm_surface_reset_drawable(void)
 {
   BLI_assert(BLI_thread_is_main());
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
 
   if (g_drawable) {
     wm_surface_clear_drawable();
diff --git a/source/blender/windowmanager/intern/wm_window.c b/source/blender/windowmanager/intern/wm_window.c
index 69c08427c4a..4c5b7194b0a 100644
--- a/source/blender/windowmanager/intern/wm_window.c
+++ b/source/blender/windowmanager/intern/wm_window.c
@@ -1115,7 +1115,7 @@ void wm_window_clear_drawable(wmWindowManager *wm)
 
 void wm_window_make_drawable(wmWindowManager *wm, wmWindow *win)
 {
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
 
   if (win != wm->windrawable && win->ghostwin) {
     //      win->lmbut = 0; /* keeps hanging when mousepressed while other window opened */
@@ -1136,7 +1136,7 @@ void wm_window_make_drawable(wmWindowManager *wm, wmWindow *win)
 void wm_window_reset_drawable(void)
 {
   BLI_assert(BLI_thread_is_main());
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
   wmWindowManager *wm = G_MAIN->wm.first;
 
   if (wm == NULL) {
@@ -2487,25 +2487,25 @@ void *WM_opengl_context_create(void)
    * So we should call this function only on the main thread.
    */
   BLI_assert(BLI_thread_is_main());
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
   return GHOST_CreateOpenGLContext(g_system);
 }
 
 void WM_opengl_context_dispose(void *context)
 {
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
   GHOST_DisposeOpenGLContext(g_system, (GHOST_ContextHandle)context);
 }
 
 void WM_opengl_context_activate(void *context)
 {
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
   GHOST_ActivateOpenGLContext((GHOST_ContextHandle)context);
 }
 
 void WM_opengl_context_release(void *context)
 {
-  BLI_assert(GPU_framebuffer_active_get() == NULL);
+  BLI_assert(GPU_framebuffer_active_get() == GPU_framebuffer_back_get());
   GHOST_ReleaseOpenGLContext((GHOST_ContextHandle)context);
 }