am i going mad? multimatte and vraymtlID elements rendering black

V-Ray for 3ds Max V-Ray for 3ds Max :: General
1

ive got a super simple scene, some shelled geometry. ive used the “override mtlID” to give a diff material to the shelled edges, something ive done 100 times. this renders fine. both materials applied to correct faces. create a multimatte, check “ISmatID” leave at default id numbers (the scene just has id’s 1 and 2 used)

multimatte renders black.

tried adding vrayMTLID element to make sure i wasnt doing some silly error with the multimatte (hard to believe but stranger things have happened) also that renders black.

what on earth am i doing wrong.. real basic level stuff… admittedly ive not touched vray for a few of months but i dont think ive lost it so badly. ive tried collapsing all to editable poly, ive tried upgrading vray, ive tried switching to GPU.. nothing.

super simple max 2024 scene attached. what totally basic step have i forgotten?!
multimatte.zip (36.7 KB)

2

Haha, yeah you went mad. You still need to assign the MatID to the materials. They are still at 0. When you override the materialID in shell modifier, it applies to Multi/Sub-ObjectMaterial, not to the actual material ID of the material itself.

Example what you need to set up for the first material: Set its ID to 1; set the other one to 2. And yes I agree the terminilogy is confusing.

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3

ok yeah its been too long. thanks :stuck_out_tongue:

4

Yeah… Polygon ID vs Material ID.

They keep asking for ID!