From 88a13e7d39ae899caa8fc13d44d44243f6482e71 Mon Sep 17 00:00:00 2001
From: alteredq <postfilter@gmail.com>
Date: Sun, 6 Mar 2011 21:47:07 +0100
Subject: [PATCH] Added safeguard in OBJ converter for not crashing on
 zero-sized degenerate normals.

---
 utils/exporters/convert_obj_threejs_slim.py | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/utils/exporters/convert_obj_threejs_slim.py b/utils/exporters/convert_obj_threejs_slim.py
index 886143c7..70e3585b 100644
--- a/utils/exporters/convert_obj_threejs_slim.py
+++ b/utils/exporters/convert_obj_threejs_slim.py
@@ -323,17 +323,18 @@ def normalize(v):
     """Normalize 3d vector"""
     
     l = math.sqrt(v[0]*v[0] + v[1]*v[1] + v[2]*v[2])
-    v[0] /= l
-    v[1] /= l
-    v[2] /= l
+    if l:
+        v[0] /= l
+        v[1] /= l
+        v[2] /= l
 
 # #####################################################
 # MTL parser
 # #####################################################
 def texture_relative_path(fullpath):
-	texture_file = os.path.basename(fullpath)
-	return texture_file
-	
+    texture_file = os.path.basename(fullpath)
+    return texture_file
+    
 def parse_mtl(fname):
     """Parse MTL file.
     """