code: public static void loadCubemapTexture(final GVRContext context,
                                           ResourceCache<GVRImage> textureCache,
                                           final TextureCallback callback,
                                           final GVRAndroidResource resource, int priority,
                                            Map<String, Integer> faceIndexMap)
              throws IllegalArgumentException
      {
          validatePriorityCallbackParameters(context, callback, resource,
                  priority);
          final GVRImage cached = textureCache == null
                  ? null
                  : (GVRImage) textureCache.get(resource);
          if (cached != null)
          {
              Log.v("ASSET", "Texture: %s loaded from cache", cached.getFileName());
              context.runOnGlThread(new Runnable()
              {
                  @Override
                  public void run()
                  {
                      callback.loaded(cached, resource);
                  }
              });
          }
          else
          {
              TextureCallback actualCallback = (textureCache == null) ? callback
                      : ResourceCache.wrapCallback(textureCache, callback);
              AsyncCubemapTexture.loadTexture(context,
                      CancelableCallbackWrapper.wrap(GVRCubemapImage.class, actualCallback),
                      resource, priority, faceIndexMap);
          }
      }
docs: Load a cubemap texture asynchronously.
  
  This is the implementation of
  {@link GVRAssetLoader#loadCubemapTexture(GVRAndroidResource.TextureCallback, GVRAndroidResource, int)}
  - it will usually be more convenient (and more efficient) to call that
  directly.
  
  @param context
  The GVRF context
  @param textureCache
  Texture cache - may be {@code null}
  @param callback
  Asynchronous notifications
  @param resource
  Basically, a stream containing a compressed texture. Taking a
  {@link GVRAndroidResource} parameter eliminates six overloads.
  @param priority
  This request's priority. Please see the notes on asynchronous
  priorities in the <a href="package-summary.html#async">package
  description</a>.
  @return A {@link Future} that you can pass to methods like
  {@link GVRShaderData#setMainTexture(Future)}