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ndeboar
09-21-2005, 07:32 AM
Hey,

This will probably show my ingnorance, but man i just dont get ambient occlusion. See attached images.

the first is my scene with out AO, the second is my scene with AO with all my lights turned off. Now, logic tells me that if AO simulates GI then with all my lights turned off i shouldnt see anything. It just doesnt seem right! Do i just have to manualy set my bright and dark values to get it 'right'?

Cheers,

Nick D
Sphere♥
09-21-2005, 03:58 PM
AO is meant to be composited despite the fact that a lot of people use it pure for draft model renders. Use AO to filter your final render, the basic idea is: it's white where light could reach easily, dark where it would be difficult for light to reach.
ndeboar
09-22-2005, 12:07 AM
Ah,

Now there is an option to render the AO into the alpha of the render, but it never seems to work for me. How do you do an AO pass?

Cheers,

Nick D
Jozvex
09-22-2005, 03:51 AM
Most people apply either the Dirtmap shader or a Surface Shader with the mib_amb_occlusion shader connected to its Out Color to all the objects in your scene, then render that.

Everything will be black and white and you can multiply/darken/add it to your regular render in Photoshop or a compositing app.

To instead renders the AO as part of the rergular image, attach the AO shader to the Ambient Color of your shaders.

:thumbsup:
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09-22-2005, 03:51 AM
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