private boolean canScrollInAllDirection() {
    return mTransformedImageBounds.left < mViewBounds.left - EPS
        && mTransformedImageBounds.top < mViewBounds.top - EPS
        && mTransformedImageBounds.right > mViewBounds.right + EPS
        && mTransformedImageBounds.bottom > mViewBounds.bottom + EPS;
  }
Returns whether the scroll can happen in all directions. I.e. the image is not on any edge.
samples/zoomable/src/main/java/com/facebook/samples/zoomable/DefaultZoomableController.java