Ask mod_tile+renderd to render and write metatile via renderd protocol. Based on tirex module.
syntax: result = osm.renderd.request(map, x, y, z1, z2, background)
Request enqueue command to rendering map 'map' with x/y/z1 cordination. And also request to render in background between zoom z1 to z2. If request fails return nil.
When z1 == z2, just ask to render single tile.
If background (boolean, optional) == true, request to render in background and do now wait for complete.
syntax: osm.renderd.set_renderd_sock('unix:/path/to/renderd.socket')
Updates pre-defined renderd_sock value.