Weird breakup of walls with Radiosity

[Albertv05]

Hey everyone-

 

I have a problem that I've been working on all day and can't seem to resolve. I am using Radiosity on a rendering I'm working on and for some reason radiosity is breaking up the wall in to seperate parts. My model is origianlly from ArchiCAD, which may be the source of the problem. I am using the ArchiCAD import wizard from plugins.angstraum.it. Is there anyway I can fix this in Viz 4 without redo-ing the import?? Thanks so much! -Al

 

[John Dollus]

Can you post a wireframe as well?

 

One thing to try: Make sure you clear all smoothing groups from the flat surfaces.

[Albertv05]

Here are two wireframes of the scene. The second image shows that wall of the left. It looks a bit odd, like the back half of it is missing. However, everything still renders out fine. It's always viewable, just radiosity is affecting it weird. Thanks for your help! -Al

 

 

[abicalho]

It looks like you need to play with face normals. Some seem to be flipped in the wrong direction.

Turn on Display Normals and make sure they're all pointing the same way. Also make sure that the vertices are welded, and that you do not have 2 vertices at the same place.

[Albertv05]

Hmm... i tried flipping the normals and that just made it worse. I also checked the vertices and they look fine. One thing that strikes me as odd as you can see from the wireframe picture above, it looks as if parts are missing. However, when I rotate the wall around they then show up. I'm stumped. Some more help would be huge-ly appreciated. Thanks so much in advance! Cheers. -Al

[William Alexander]

Try the smoothing groups suggestion,

 

Then what is the meshing size? You maybe getting shadow artifact from the floor geometry actully going under and past the wall geometry / intersecting it. Although I've never seen artifact quite so well defined. Maybe try to take some of the edges of the floor plane and make them coplaner with the wall, see if that makes a difference.

 

Cheers

WDA

[Buffalo Bills]

Albertv05,

 

Sometimes I get the same results with the models I build. When using radiosity and getting rid of the different colorization in your walls, you might want to try using regather indirect illumination. It is found in the rendering parameters rollout. Check the regather indirect illumination box and set the rays per sample to 150 and filter radius to 10-15. Then calculate radiosity and hit render. This might solve your problem. It will also take a long time to render. But try it and see. I don't know of any other ways of correcting your problem that the others haven't mentioned already. Keep us posted!

[Albertv05]

Re-gathering indirect illumination did it!! I couldn't have done it without you guys , I'm completely in dept. If i could give all you guys some of my homebrew I would! Now I can finally move on and finish up this rendering!!

 

Thanks again! -Al

 

[Psychoscorpic]

I also get that sometimes, and not from imported models (normally model in DataCAD, because I cut my teeth on it, but I get this problem most from VIZ-4 modelled faces)

 

Since my models are often very detailed complexes, I cant afford the rendertime hit for regather (can add an hour or more), so normally delete the faces and re-make them.

 

I'd like to know the cause, as it can be a real pain sometimes.

[MegaPixel]

Pyshco - You could exclude your detailed meshes from the Refine Iterations calc to save some time.

[Psychoscorpic]

Pyshco - You could exclude your detailed meshes from the Refine Iterations calc to save some time.

Thanks, MegaPixel - will give that a bash right now - complex terrain (from Civil's TIN) etc doesn't need the refining. Never thought of that.