In article <web.3d556659fa75637ea3c6bc9f0@news.povray.org>,
 "Jurjen" <jjs### [at] hotmailcom> wrote:

> Here is some code that will change the behaviour of smooth-triangles:
> - It will trim the triangles so the spots with inverted normals get
> transparent.
> - This also trims the triangles towards the light source so there will be
> less shadow on triangles behind a smoothed triangle.

I have been wondering about this as a possible solution to the inverted 
normal problem, I've just been too lazy to try it out...nice work!

Actually, the variation I was thinking was this: if the smoothed normal 
is pointing in the direction of the ray, skip that intersection *and the 
next one*, but then go on as usual. In most well-behaved meshes, this 
should have the effect of "chopping off" the areas with the bad normals 
like your patch, but still let the inside of the mesh render, leaving 
the mesh still useful for things like media.

I think your change might have another side effect: it will always let 
rays go through the entire mesh, even if the area that has the reversed 
normal is in front of an area with a correct normal. I'm not sure 
though, I haven't applied this patch to see where it goes.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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