[Feature Request] Specifying draw order

[alexmozaidze]

It would be quite useful to be able to specify draw order for objects. At the moment, one must implement draw ordering on his own, which basically restricts you from using world:draw, and it's quite unfortunate due to how simple it is to use.

[HDictus]

Good idea. Should be simple enough to do, just need to sort the list of colliders by some order attribute.

[HDictus]

see #17