>> Pd doesn't care about z-ordering at all and the order of drawing is
>> mainly defined by "what needs to be done" (rather than: "how will it
>> look like").
> I don't agree that there is no defined z-ordering in Pd, otherwise you couldn't reliably build GUIs.
Scalars in Pd Vanilla don't have a well-defined z-order:
1. Display a scalar square on top of a scalar circle
2. Delete the scalar circle
3. Undo the delete
Now the scalar circle is displayed on top of the scalar square.
Pure Data ought to retain the z-ordering in this and other circumstances. If it
doesn't please submit a bug and I'll fix it.
Best,
Jonathan