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Dromond
04-02-2006, 07:31 PM
Generally when I want to render the shadows cast by an object but not the object itself I turn off its Primary Visibility. However I have a particular situation where I have a piece of geometry intanced for every particle in a group. Turning off the primary visibility for the particles, the intanced geometry or the instancer itself doesn't seem to do the trick. Is there a way to render only the shadows cast by instanced geometry?

cheers

leif3d
04-02-2006, 07:47 PM
The way I would aproach it would be to make a new scene, Shade everything you want to cast shadow a white lambert with the ambient white and diffuse white. Set your background color to be white and then render an occlusion or shadow pass. Later composite the pass as a multiply layer in a compositing program. Hope that helps.

mindsample
04-02-2006, 07:58 PM
Generally when I want to render the shadows cast by an object but not the object itself I turn off its Primary Visibility. However I have a particular situation where I have a piece of geometry intanced for every particle in a group. Turning off the primary visibility for the particles, the intanced geometry or the instancer itself doesn't seem to do the trick. Is there a way to render only the shadows cast by instanced geometry?

cheers

I am not sure if I understand but could you not just use the attribute spreadsheet?

Dromond
04-02-2006, 08:06 PM
I am not sure if I understand but could you not just use the attribute spreadsheet?

I am using the attribute spreadsheet. Geometry instanced with the instancer has no primary visibility attribute. This is the root of my problem. :(

leif3d
04-02-2006, 08:16 PM
turn the primary visibility on and shade the objects as I said. This should give you a black and white image where the shadows are shades of gray and the rest of teh image is white, you can multiply this as an apply mode to the other composit layers.

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04-02-2006, 08:16 PM
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