View Full Version : Shadow extracting from lights

05-28-2012, 09:20 PM
I have in scene a few lights. Is there any chance to extract shadow buffer from only one light ? As default Lightwave shadow buffer is a mix of all lights shadows in a scene. I need to extract only one light shadow.

Or is there possibility of getting a cast shadow mask only by the given object ?

I've played with DP Filter buffer nodes, but don't know how to connect lights into to them.

Thanks for help.

06-03-2012, 08:39 PM
You might want try DP LightGroup (http://dpont.pagesperso-orange.fr/plugins/nodes/nodes/Shadows.html#LightGroup) in a similar way as proposed here (http://lightwiki.net/wiki/Multipass_Rendering_with_Filter_Node_Editors#Light s_Pass). Have to update the article but use a Prefix for the light (or group of lights) you want isolate, and try Shadows output instead of DiffColor output for extracting the shadow component.


Areyos Alektor
06-07-2012, 06:16 PM
There are several options I think, but why not simply disable the shadows for the other lights? (Lights Properties/Shadows/Shadow Type=off)

06-07-2012, 07:49 PM
It's an option if there's no problem with rendering the scene again (or managing a new scene again if you are network-rendering) just for a single shadow buffer. Has more sense try to get all the buffers as possible in a single render, mostly if you need the same buffers frequently in your projects. But sometimes that's not possible i.e.: if LightGroup shadow buffer doesn't match with the actual shadow, then you might want disable not only the shadows of the other lights but also all the other properties of those lights for speeding up that render layer. If you need manage render layers frequently, Janus (http://faulknermano.com/janus/overview.html) may be very useful.