1 reply to this topic

[dtom]

Hi all,

I've been working on implementing ambient occlusion into my lightmap toolset, and for the most part I've been very pleased with the results.

There's one problem that I've consistently encountered, though, and from what I can tell it's also found in most commercial renderers.

Whenever the environment i'm lightmapping has geometry that intersects, I get black seams along the line of intersection. This happens because the rays that are being cast for a texel are hidden behind the intersecting geometry, rendering the both the visible and hidden portions of that pixel black. One way to reduce the artifacts is to crank up the lightmap resolution, thereby making the texels smaller and artifacts less noticeable. I was wondering how other people have dealt with the problem of seams in their ambient occlusion lightmaps (and other lightmapping procedures, including shadow casting).

Thanks for any help you can offer!

[Reedbeta]

Well, one way is to remove intersecting geometry.

That may sound flippant, but really...if you are running a preprocessing pass to compute ambient occlusion, you can certainly afford to take the time to make sure you have proper tesselated and welded meshes, with no intersecting geometry.