new file mode 100644
--- /dev/null
+++ b/pytouhou/opengl/background.py
@@ -0,0 +1,46 @@
+# -*- encoding: utf-8 -*-
+##
+## Copyright (C) 2011 Thibaut Girka <thib@sitedethib.com>
+##
+## This program is free software; you can redistribute it and/or modify
+## it under the terms of the GNU General Public License as published
+## by the Free Software Foundation; version 3 only.
+##
+## This program is distributed in the hope that it will be useful,
+## but WITHOUT ANY WARRANTY; without even the implied warranty of
+## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+## GNU General Public License for more details.
+##
+
+#TODO: lots of things
+
+from struct import pack
+from itertools import chain
+
+from pytouhou.opengl.sprite import get_sprite_rendering_data
+
+def get_background_rendering_data(background):
+    #TODO
+    try:
+        return background._rendering_data
+    except AttributeError:
+        pass
+
+    vertices = []
+    uvs = []
+    colors = []
+    for ox, oy, oz, model_id, model in background.object_instances:
+        for ox2, oy2, oz2, width_override, height_override, sprite in model:
+            key, (vertices2, uvs2, colors2) = get_sprite_rendering_data(sprite)
+            vertices.extend((x + ox + ox2, y + oy + oy2, z + oz + oz2) for x, y, z in vertices2)
+            uvs.extend(uvs2)
+            colors.extend(colors2)
+
+    nb_vertices = len(vertices)
+    vertices = pack(str(3 * nb_vertices) + 'f', *chain(*vertices))
+    uvs = pack(str(2 * nb_vertices) + 'f', *chain(*uvs))
+    colors = pack(str(4 * nb_vertices) + 'B', *chain(*colors))
+
+    background._rendering_data = [(key, (nb_vertices, vertices, uvs, colors))]
+
+    return background._rendering_data