shadow problems

# 1 14-02-2004 , 03:19 AM

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Join Date: Dec 2002

Location: CA

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Hi,

I have lit this scene with an ambient light of intensity 0.2 and a directional light of intensity 0.8. shadows are being cast only by the directional light.
But I'm getting this weird shadow pattern on my renders.

WHY?

P.S. I tried lighting this with just an ambient and then only a spot light and it renders just fine...

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~nspiratn

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# 2 14-02-2004 , 03:28 AM

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Join Date: Dec 2002

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bring up the filter size to 3 for the light shadow. Also the setting jst below the filter size to .03. Sorry don't have maya open so can't tell exactly. What you are getting in just some artifacting from the Depth map shadow.

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# 3 20-02-2004 , 10:20 AM

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Location: London, UK

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up the dmap resolution, and only then start to fiddle with the bias and filter settings. It's basically artifacts.

explanation: it renders fine as a spot because it is illuminating a much smaller area (trhe size of the cone angle). With a directional light it is illuminating everthing from that direction. So the dmap res is split up over a much larger area. By increasing the map res it will increase the average spread of the map's resolution.You can also use light linking to reduce the amount of geometry being illuminated by the light, that will also help out the shadow problem.

Alan

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Currently working on: Your Highness

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# 4 26-02-2004 , 04:49 AM

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Location: Ontario, Canada

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Another solution is to use raytraced lights. Sure, rays are slower, but if you need to use really huge dmaps it can sometimes be faster to use rays instead.

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# 5 26-02-2004 , 10:09 AM

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yeah but then you will get hard edged shadows... and if it's a large scene unless you optimise which objects are going to get raytraced then you will end up with higher render times...

Technical Director - Framestore

Currently working on: Your Highness

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# 6 26-02-2004 , 10:24 PM

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Location: Ontario, Canada

Posts: 15

If you want soft edges with raytracing simply increase the number of rays to between 15 and 30. Also adjust your Light Angle (this is called a Radius on point lights). This IS going to be slower rendering, but the quality will look much better.

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