private void modifyTexture(
            final Texture2D textureAtlas,
            final com.jme3.texture.Image image,
            final int x,
            final int y) {
        Renderer renderer = display.getRenderer();
        if (renderer == null) {
            // we have no renderer (yet) so we'll need to cache this call to the next beginFrame() call
            modifyTextureCalls.add(new ModifyTexture(textureAtlas, image, x, y));
            return;
        }

        // All is well. We can execute the modify right away.
        renderer.modifyTexture(textureAtlas, image, x, y);
    }
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