I tried searching and googling, but found only answers pertinent to transparency.
Is there any way to sort the rendering of two quads in the same layer (say, the x/y-plane, two quads passing through the same space). I’m not (I think) asking about transparency here, just making sure that quad a is shown instead of quad b when they are in the same space (render-wise).
The question either doesn’t make sense or is trivial.
Either you mean that the two are completely parallel to one another… in which case the answer is pretty trivial. Or you mean that they are potentially not parallel to one another in which case the answer is impossible (as they may interpenetrate).
Take a step back and tell us what you are actually trying to do.
Not until now do I understand what this means in this context.
I’ll give that a go:
My map has tiles that should be displayed either on top of, or beneath the player as the player moves in to them. Consider them a sort of roof or floor. Every tile and the player is placed in the same 2d plane (x-y). So when I create this specific tile on the client side, I’d like to force that it should be rendered ‘last’ or ‘first’ depending on the tile type.
If you use parallel projection with z as depth then you can also set the geometry comparator to that one that the guiNode uses. It uses a simplified sort on z.
Since it sorts back to front, you can put transparent and opaque tiles in the same bucket without issue.