My solution was merely to increase the angle to something like >95
degrees or so until results are good.  Actually, I don't think that for
your hair at least that 90 degrees is going to be enough...ie, since the
hair sticks up from the object and is visible beyond the surface.  My
solution would draw excess hairs, but fewer than covering the entire
surface

Steve


Margus Ramst wrote:
> 
> The mirror problem is relatively easy to overcome; a very crude approach
> would be to trace a ray from all the corners of the mirror's bounding box.
> If the sample point is invisible to all these rays, we can safely deduct
> that the point is not visible to the mirror.
> Multiple mirrors would still present a problem, but solving that wold get
> too complex (parse time is an issue, too). Culling would have to be turned
> off in that case.
> I just downloaded the paper suggested by Jerry, I'll see if this provides a
> more plausible solution...
> 
> I can't quite visualize a solution for the second problem. When the angle
> between the camera ray and the surface normal is >90 degrees, the point is
> not visible (provided that all normals point outwards). But how do I know
> how far the point is from the nearest visible point?
> The answer may be simple, but I don't have it. Perhaps you would describe
> how you'd go about solving it?
> 
> Margus
> 
> Stephen Lavedas wrote in message <36E1DA3E.44410F86@virginia.edu>...
> >I'd be happy to work with you on it.  Actually I have a few ideas.. the
> >first being to add a "culling" keyword (ie you know there is a mirror
> >somewhere, so you need all the hair) or perhaps to give the vector to
> >the mirror and calculate off of both.  The other is to add a margin to
> >the occlusion formula.  Don't occlude EXACTLY at the point where the
> >point is no longer visible..occlude 5 degrees further or some such.
> >
> >Steve
> >(of course I still need to dl the super patch)
> >

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