@Override
    public void fillRemovedImagesInAtlas(final boolean shouldFill) {
        fillRemovedTexture = shouldFill;
    }
Whether or not to overwrite previously used atlas space with blank data.
Setting to true will result in slower performance, but may be useful in
debugging when visually inspecting the atlas, since there will not be
portions of old images visible in currently unused atlas space.

@param shouldFill true&rarr;overwrite with blank data, false&rarr;don't
overwrite
jme3-niftygui/src/main/java/com/jme3/niftygui/JmeBatchRenderBackend.java