protected void loadTextures(AssetManager manager) {
   normalTexture =
       (Texture2D) manager.loadTexture("Common/MatDefs/Water/Textures/water_normalmap.png");
   dudvTexture = (Texture2D) manager.loadTexture("Common/MatDefs/Water/Textures/dudv_map.jpg");
   normalTexture.setWrap(WrapMode.Repeat);
   dudvTexture.setWrap(WrapMode.Repeat);
 }