Envelope2D env = SlippyTile.tile2Envelope(x, y, z);
TileRequest tileRequest = new TileRequest("", env, 256, 256);
RoutingRequest sptRequestA = buildRequest(0);
RoutingRequest sptRequestB = buildRequest(1);
Layer layer = layers.get(0);
Style style = styles.get(0);
RenderRequest renderRequest = new RenderRequest(format, layer, style, true, false);
return null; //renderer.getResponse(tileRequest, sptRequestA, sptRequestB, renderRequest);
}