View Full Version : how to render Occlusion?

09 September 2007, 07:54 PM
Didnt find anything about it on the Help file, anything but a node called dgs_material from Mental Ray.

How do I render a occlusion pass?

09 September 2007, 08:41 PM
The node is called mib_amb_occlusion and mib_fg_occlusion.
The fit well in the ambient- or incandescence slot of any material.

Just search the mental ray documentation (accessible via the maya doc) for a more detailed description.

An easy way to do an occlusion pass is to assign mib_amb_occlusion to a surface shader material. Assign it to all objects in your scene (you can use a render layer with material override) and render it.

09 September 2007, 09:12 PM
or you can simply use the occlusion template from render layers ...

09 September 2007, 04:59 PM
Two ways to do that... manually using FG and a simple surface shader or by creating an occlusion layer in Maya.

Method 1: Create a surface shader... assign mib_amb_occlusion to all objects in the scene. Render with Final Gather.

Method 2: Add all required objects into an empty Render Layer... Use the Occlusion Preset and hit Render.

Ps. Make sure the camera background is white

09 September 2007, 05:03 PM

this should cover everything you'll need

09 September 2007, 06:38 PM
Just curious, which attribute of the surface shader gets the connection from the AO's output? I've been able to get AO with the render layer preset as well as plugging it into a lambert but wasn't so successful trying to use a surfaceshader.

09 September 2007, 06:46 PM
Just curious, which attribute of the surface shader gets the connection from the AO's output?

.outValue > .outColor

09 September 2007, 04:59 AM
Awesome! Thanks a lot!

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09 September 2007, 04:59 AM
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