diff --git a/tools/convert-mesh/bin/convert-mesh.py b/tools/convert-mesh/bin/convert-mesh.py
index 698faf07..b2c33374 100644
--- a/tools/convert-mesh/bin/convert-mesh.py
+++ b/tools/convert-mesh/bin/convert-mesh.py
@@ -62,11 +62,11 @@ smooth_index = {}
 def append_vertex(v, n):
 	vertex_coords.append((v.co.x, v.co.y, v.co.z))
 	vertex_normals.append((n.x, n.y, n.z))
-	if colors:
+	if colors is not None:
 		vertex_colors.append(tuple(colors[li].color))
-	if texcoords:
+	if texcoords is not None:
 		vertex_texcoords.append((texcoords[li].uv[0], 1.0 - texcoords[li].uv[1]))
-	if armature:
+	if armature is not None:
 		weights = []
 		for g in v.groups:
 			name = obj.vertex_groups[g.group].name