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Old 12-03-2011, 07:52 PM   #1
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Default ambient occlusion ray direction

how to i change the lighting direction for the ambient occlusion to match my scene lighting
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Old 12-03-2011, 08:08 PM   #2
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I dont think you can on light direction(will be proved wrong) if you show a shot of the problem there might be another solution..........dave
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Old 12-03-2011, 08:41 PM   #3
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the model is lighted from underneath, but the occlusion is as lighted from above, i guess i could flip my model upside-down for the occlusion pass but that seems odd method to me
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Old 12-03-2011, 08:54 PM   #4
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ambient occlusion is created from the models geometry not a light source that is way I said show us a shot a sreen shot to see if we can help..........dave
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Old 14-03-2011, 03:21 PM   #5
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i think i understand the problem then, i have a white floor under the model to reflect light up onto it, on the occlusion pass i guess this is actually making some areas darker
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Old 15-03-2011, 05:29 PM   #6
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yep works ok now
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Old 15-03-2011, 10:58 PM   #7
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i think the problem is misunderstanding ambient occlusion... which creates contact shadows when one object is close to another. you can turn off ambient occlusion on specific geometry. would this be helpful to you?
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Old 16-03-2011, 08:05 AM   #8
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thanks Dom for clearing that up.

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Old 16-03-2011, 09:53 AM   #9
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if you want to have an object not occlude itself.
select the geometry, create an attribute called "miLabel" then in the ambient occlusion node you will see an attribute called id nonself. I think (can't really remember) but if you set both these attributes to the same value, the geo will not occlude. i could be wrong about the values, so i would just play around with the settings.
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