Non Metallic Workflow Support

src/Materials/babylon.pbrMaterial.ts

@@ -938,7 +938,7 @@
                 this._defines.RADIANCEOVERALPHA = true;
             }
 
-            if ((this.metallic !== undefined && this.metallic != null) || (this.roughness !== undefined && this.roughness != null)) {
+            if ((this.metallic !== undefined && this.metallic !== null) || (this.roughness !== undefined && this.roughness !== null)) {
                 this._defines.METALLICWORKFLOW = true;
             }