Hi,
Can someone please show me how I can assign more than one “shader”sop to one object? e.g. face no. 1,5,7 for shaderA and face no. 2,3,4,6 for shaderB.
I tried to group faces differently with the “group” sop and attach to differnt “shader” sop, then merge them together but it does not work.

thank your for your attentions!

Ok, here may be a solution.

I took a polybox, created one group with 2 poly faces, then in the same group node under the compliment tab I created a second group, I put the other 4 faces in a second group. Then wired the group sop into the first shader sop with one shader and finally wired the same shader sop into a second shader sop with using a different shader. Each shader sop was applied to a different group. When rendered, its seemed the groups retain shader properties correctly. All in one chain.

You may want to keep your network as one chain, instead of branching the model into groups and merging them. The merge sop may be causing the problems….the UV's can get tweaked once the poly groups are merged. Anyhow, try creating your groups first in a single chain and then assign them shaders down the same chain.

talos72,
thank you for your reply
but I cannot find compliment tab in Houdini7. I could only find “combine” tab. Also, How can I create a 2nd group in the same group node?
pattern 1 2 ,5 6?
thanks anyway!

Sorry about that…by compliment I meant using the Combine tab. Ok, first pick all the poly faces you want in one group and name that group. You should see the primitive numbers in the pattern parameter just to make sure the group has the polygons you want.

Next go to the Combine tab, in the box on the left type the name of the new group which will be the compliment of the original group (contain the rest of the polys not originally picked). Then click the button in the middle to get the “exclamation” sign to appear (it is actually the logical NOT sign, if you are familiar with programming logic). Finally, in the box on the right type the first group's name. Now in one Group SOP you have created two complimentary groups.

If you want to create groups that are not necessarily compliments, just keep adding new Group SOPs down the same chain (each containing the specific polygons you want). In your example, first Group SOP has polys 1 and 2, then wire that SOP into a second Group SOP which will contain polys 5 and 6.

In either case, once you make your groups, then you can assign them shaders again by adding Shader SOPs down the same chain, each referencing a different group up the chain.

talos72
thank you very much! It works!

Glad to be of assistance. 8)