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duke
08-24-2007, 12:24 AM
Is there a way to do this with nodes, where radiosity/GI uses one surface but the actual render outputs another, so you can have a blue surface seen to GI, but in the render its a flat white so you can effectively bake out a GI-only pass?

jameswillmott
08-24-2007, 12:28 AM
Try using the Preprocess output on the Spot Info node to switch materials around like that. I use it on glass in internal archvis shots to make it luminous to radiosity but transparent to camera rays. Saves having to put area lights outside every single window.

nthused
08-24-2007, 06:22 PM
Try using the Preprocess output on the Spot Info node to switch materials around like that. I use it on glass in internal archvis shots to make it luminous to radiosity but transparent to camera rays. Saves having to put area lights outside every single window.

OK, James, please attach a screenshot. This sounds interesting - something I just wouldn't even think about. Thanks.

duke
08-25-2007, 01:20 AM
I thought something like this but it obviously isn't it!

http://dukecg.net/pre-processSwitch.jpg

jameswillmott
08-25-2007, 06:11 AM
Sampled Ray, not Preprocess... ( shows up in soft reflections unfortunately too )

My bad.

The rest of the graph is right as long as SeenToGI is True and SeenToCamera is False. (can't tell from your image )

duke
08-25-2007, 09:07 PM
(little kid on trike from The Incredibles) Wicked!

http://www.dukecg.net/GIbufferTest.jpg

jameswillmott
08-26-2007, 05:43 AM
Spooky huh? :)