From 1d43bd0f39a955041b51e8589e8d12da49eb2ba9 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Thu, 22 May 2014 13:44:36 +0000
Subject: [PATCH] Reset the state and transform before the end_frame callback
 (needed for Blender integration)

---
 panda/src/display/callbackGraphicsWindow.cxx | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/panda/src/display/callbackGraphicsWindow.cxx b/panda/src/display/callbackGraphicsWindow.cxx
index d89f7bc833..6de33cc9d6 100644
--- a/panda/src/display/callbackGraphicsWindow.cxx
+++ b/panda/src/display/callbackGraphicsWindow.cxx
@@ -124,6 +124,11 @@ begin_frame(FrameMode mode, Thread *current_thread) {
 void CallbackGraphicsWindow::
 end_frame(FrameMode mode, Thread *current_thread) {
   if (_render_callback != NULL) {
+    // In case the callback or the application hosting the OpenGL
+    // context wants to do more rendering, let's give it a blank slate.
+    _gsg->set_state_and_transform(RenderState::make_empty(), _gsg->get_internal_transform());
+    _gsg->clear_before_callback();
+
     RenderCallbackData data(this, RCT_end_frame, mode);
     _render_callback->do_callback(&data);
   } else {