Stephen Lavedas wrote:
> 
> 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

With some objects, it would work. With others, it wouldn't. Consider a box.
There is a very sharp change in normal direction at the edge. The
normal/camera difference could be up to 180 degrees, yet the point could lie
next to a visible point and culling shouldn't take place. You could argue that
the existing hairs would obscure this shortcoming. But if the box were very
thin, the lack of hairs on the backside would become visible.
Still, this solution is nice and simple. Anything better would need to have
some kind of a sorting algorithm, I'm afraid. Perhaps I'll let the user
specify a culling angle. 180 degrees - no culling. 0 degrees - nice and bald
:)

Margus

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That is kinda what I was going for, a solution that while not perfect it
is easy to implement.  I actually kind of considered the variable angle
as a solution.  Just after I posted the message.  Let me know how it
turns out.

Steve


Margus Ramst wrote:
> 
> Stephen Lavedas wrote:
> >
> > 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
> 
> With some objects, it would work. With others, it wouldn't. Consider a box.
> There is a very sharp change in normal direction at the edge. The
> normal/camera difference could be up to 180 degrees, yet the point could lie
> next to a visible point and culling shouldn't take place. You could argue that
> the existing hairs would obscure this shortcoming. But if the box were very
> thin, the lack of hairs on the backside would become visible.
> Still, this solution is nice and simple. Anything better would need to have
> some kind of a sorting algorithm, I'm afraid. Perhaps I'll let the user
> specify a culling angle. 180 degrees - no culling. 0 degrees - nice and bald
> :)
> 
> Margus

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