Uber Point Cloud Based Light Shader

UPDATE:10/19/2010
It now works correctly with 3Delight materials. Still having trouble with mia materials.
Added SSS to PTC usage section.

UPDATE:11/2/2010
Added AOV support for the newest 3Delight versions.
Fixed numerous bugs.

UPDATE:11/9/2010
Added directional occlusion, a tweak on occlusion that makes it kind of like a soft directional light
Fixed some hints on the Max Variation parameter
IBL may not have been working before
Samplebase isn’t a PTC option, oops

UPDATE:11/22/2010
Added the ability to rebake and reuse PTC data to save rendertime when multiple renders are needed

UPDATE:1/3/2012
Added the ability to composite or not composite the effect onto the render.

UPDATE:1/4/2012
Added SSS presets

I’ve compiled the shader as a light shader now.

You can’t have multiple atmosphere shaders on top of the same object, so that was limiting. With both ways, you can render out multiple effects at one time. The difference being that with the atmosphere shader, you have one shader with many effects and a pass for each effect, and with the light shader you have lots of light shaders you can link to objects however you want. The key downside for the light shader is that using custom AOVs won’t work unless you hardcode those AOVs into the surface shader. So, for every surface shader in your scene, you have to add in the code to allow them to pass along the custom AOVs. Whereas with the atmosphere shader, you don’t have to.

Here are the several key differences in this shader vs. the atmosphere version.

• There is no baking function for the light shader. You can either use my ptc_uber or your own shader to bake
• Gamma correction is gone, but each section has an intensity multiplier so you can control the effect.
• No AO section under GI. I haven’t tested using multiple options at the same time, but there’s no use for that because you can very easily add another light with another instance of this shader for the added effects. That is also the reason for taking out AO under GI. If you want both, use two lights, one for AO, one for GI. Simple enough.

Download cl_ptc_light_uber.sl