radiosity issue....

[chuck]

hello all,

 

i'm working with max 5 trying to get a good set of radiosity images for my final critique. where faces meet i keep running into a "zipper" effect for lack of a better term. anyone know how to fix this? it seems objects that are boolean'd dont have the issue, just where boxes overlap...filtering helps a bit, but then everything looks well, too filtered.

 

radiosity is set at 85%, regathering is on, filter at 3, refining at 3, logorithmic exposure is on with default settings. meshing is also on.

thanks for any help,

 

http://www.cgarchitect.com/forum/filepush.asp?file=6_5.jpg

 

 

chuck

[Fran]

Hi Chuck,

 

You have to model very efficiently in order to get the best results with radiosity. Since the indirect lighting calculation is stored in what's called a "receiver mesh", surfaces that intersect each other at a point other than an edge with will have light and shadow that leaks. That is why your boolean surfaces perform better.

 

In your scene, the wall extends below the floor, so the shadow that is being cast onto the wall by the floor is bleeding up through the intersection. This effect is more or less pronounced depending on the size of the mesh.

 

Ordinarily, such artifacts disappear when you render with regathering. What are your settings for that?

[chuck]

fran,

 

thanks for the help. the regathering settings are 150 rays per sample with a filter radius of 5.

clamped values are off, as is adaptive sampling.

 

as far as modeling techniques, should the boxes not overlap at all, touching only at a specific point (line)?

 

thanks again,

 

chuck

[chuck]

well after a night of rendering with a larger filter radius (10) all is good....

 

thanks again,

 

chuck