Update ColladaMeshShape.java

Author: christianliebl

src/gov/nasa/worldwind/ogc/collada/impl/ColladaMeshShape.java

@@ -1192,6 +1192,9 @@ protected String getTexCoordSemantic(Geometry geometry)
      */
     protected String getTextureSource(ColladaAbstractGeometry geometry)
     {
+        if (this.bindMaterial == null)
+            return null;
+        
         ColladaTechniqueCommon techniqueCommon = this.bindMaterial.getTechniqueCommon();
         if (techniqueCommon == null)
             return null;
@@ -1297,7 +1300,10 @@ protected String getImageRef(ColladaEffect effect, ColladaTexture texture)
      *         available.
      */
     protected ColladaEffect getEffect(ColladaAbstractGeometry geometry)
-    {
+    {   
+        if (this.bindMaterial == null)
+            return null;
+            
         ColladaTechniqueCommon techniqueCommon = this.bindMaterial.getTechniqueCommon();
         if (techniqueCommon == null)
             return null;