Ah, ok - I'm with you. I originally coded the system to be similar to what you describe, however in practice some issues came up. The main one being if the user tweaks a particular material (say SkinHead), but not the other materials, you'll get a seam at the neck (since the materials are different) - so there became a need to enforce a certain node structure. Also, it's possible for the user to corrupt a node setup by disconnecting something, so any script that changes the nodes needs to be able to "fix" the node network. So in the end it becaome an impractical solution, and I went with a system with enforces a particular node setup, and allows the user to change the node values via the python interface. The next version of the system (which I am working on at the moment) allows a bit more flexibility, in that the user can change the node network, and as long as particular ndoes are present, and connected, the script will assume the node network is valid, and just change the values.

Creator of PoserPhysics
Creator of OctaneRender for Poser
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