@jwunderl @CarltonFade @Kiwiphoenix364
Hi guys!
as to the multi-level and floor/ceiling:
Thanks for your valuable suggestions! These will be adopt when I coding them.
I did some test, the FPS will down to about 8 on device/console with just drawing walls twice. So this extension is not fast enough to do these features right now, I think. We can’t add these until perf has a significant impovement some day.
But, I know, these are all attractive features, I love them too. I will do my best to optimize perf furture. I am thinking about a new optimized algorithm based on raycasting. But it is a big change, need some time to rewrite almost ALL the rendering codes of walls, and then check it works or not.
Hope I can made it. 
And leave your comments above 2 new previews pls. It won’t be merge into the extension, until you are satisfied with these results.
Thanks a lot for your support as always!