[Bf-committers] Feature idea: material assigment for modifiers

[Bassam Kurdali]

 I spoke with Campbell on irc, and he suggested I mail this to the list
as a general proposal. It came up from me wanting a different material
assignment for the inner and outer faces of a solidify modifier (as
opposed to just the rim).

 Campbell suggested that hacking this in would be easy but a bit ugly;
he proposed that a more generalized feature that would work for any
modifier, in a consistent way, would be better. Indeed I could easily
imagine this being desirable for at least:

Solidify (currently just rim, but also inner outer)
Mirror
Bevel
Array
Boolean (already works by inheriting original materials?)

List of concerns:

-Blender does not guarantee material order is the same (e.g. when
joining)
-a way to modify materials used might not work reliably
-doing it only for Solidify feels arbitrary, since it might be useful
anytime you generate new faces-a more general way would be better (hence
this proposal)
-referencing material by index is "crappy and likely to break"
-referencing directly could work, with the restriction that it exists in
the mesh/object (is this a certain restriction? could it just be there
in the scene?)
-referencing the materials using an offset rather than index, so you can
have multiple materials assigned to the mesh, and offset them for
generated faces.
-an imperfect but general known way that works for all modifiers would
be acceptable.

I think I've covered everything we talked about; My current need is only
for solidify (rigged thin sheets with a requirement to have something
only printed on one side)- and I can work around this in multiple ways,
so no real pressure. A more general solution would be more useful/
future proof.

cheers
Bassam

PS- whatever the choice, the assignment, whether by material, index, or
index offset should be visible in the modifier panel; just a checkbox
would be ultimately ugly, since (other than tooltips) there would be no
user visible/adjustable way of selecting the required material. (you can
do so for indexes in the material properties by putting the right
materials in the right slots, but this feels quite hidden)