Slime <slm### [at] slimelandcom> wrote:
> To determine if point A is inside the mesh, with the information that point
> B *is*, shoot a ray from point A to point B, counting the number of times it
> intersects the mesh. If it intersects an even number of times (counting 0 as
> even), then A is inside the mesh.

  Possibly, but AFAIK the intersection test of a ray and the mesh returns
all the intersections, so you would have to discard those which are farther
away than the segment AB. A much easier solution is just to shoot a ray
to some direction and if it returns an odd number of intersections, then
it's inside... :)
  Besides, that avoids the problem that you accidentally give a wrong B
(ie. one which is actually outside the mesh).

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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