Moving blender render files to be accessed via pkg_resources

Previously the .blend and .py files had to be in the same directory
mediagoblin/celery launched from.  This is now fixed so it pulls them
out of the package proper.

mediagoblin/media_types/stl/processing.py

@@ -18,6 +18,7 @@ import os
 import json
 import logging
 import subprocess
+import pkg_resources
 
 from mediagoblin import mg_globals as mgg
 from mediagoblin.processing import create_pub_filepath, \
@@ -29,6 +30,17 @@ from mediagoblin.media_types.stl import model_loader
 _log = logging.getLogger(__name__)
 SUPPORTED_FILETYPES = ['stl', 'obj']
 
+BLEND_FILE = pkg_resources.resource_filename(
+    'mediagoblin.media_types.stl',
+    os.path.join(
+        'assets',
+        'blender_render.blend'))
+BLEND_SCRIPT = pkg_resources.resource_filename(
+    'mediagoblin.media_types.stl',
+    os.path.join(
+        'assets',
+        'blender_render.py'))
+
 
 def sniff_handler(media_file, **kw):
     if kw.get('media') is not None:
@@ -55,7 +67,12 @@ def blender_render(config):
     arg_string = "blender -b blender_render.blend -F "
     arg_string +="JPEG -P blender_render.py"
     env = {"RENDER_SETUP" : json.dumps(config), "DISPLAY":":0"}
-    subprocess.call(arg_string.split(" "), env=env)
+    subprocess.call(
+        ["blender",
+         "-b", BLEND_FILE,
+         "-F", "JPEG",
+         "-P", BLEND_SCRIPT],
+        env=env)
 
 
 def process_stl(entry):