Thanks Kelvin.
Can we expect any better implmentation for the polygon
triangulation problem in the next release? Just as my last post
http://swjscmail1.java.sun.com/cgi-bin/wa?A2=ind0211&L=java3d-interest&D=1&O=D&F=&S=&X=6631E23B2F5652D95B&[EMAIL PROTECTED]&P=38077
shows, Java3D usually generates some long-small triangles, which normally is
not an optimized meshing for the original polygons. I have a lot of models
demonstrating that.
Thanks. ---white
>As mention in previous mail it is because after
>v1.cross(v1, v2);
>v3.cross(v2, v3);
>
>one of v1 and v3 is close to zero in the 2 other cases
>so normalization fail and can't produce result 1 or -1.
>
>I would change this :
>
> eps = v1.dot(v3);
> System.out.println("eps = " + eps);
> if (eps < 0 && (eps + TOL) < 0) <===== reductant SAME as
> (eps < -TOL)
> return true;
>
>to
> eps = v1.dot(v3);
> System.out.println("eps = " + eps);
> if ((eps > -1 - TOL) && (eps < -1 + TOL))
> return true
>
> if ((eps > 1 + TOL) || (eps < 1 - TOL)) {
> System.out.println("This algorithm fail !!");
> exit(1);
> }
>
>
>Note that in the next v1.3.1 beta release
>4712222 - PickRay computation is not numerically stable
>
>is fixed by re-implement point in triangle test for PickResult
>and the core using Solution 3 of
>
> http://astronomy.swin.edu.au/~pbourke/geometry/insidepoly
>
>which is more robust.
>
>So when beta release please check out the utility source code
>of PickResult.
>
>The good thing about utility that you can freely modify and
>suit your need such as handle this kind of corner case which
>Java3D may not handle quite well.
>
>- Kelvin
>----------------
>Java 3D Team
>Sun Microsystems Inc.
>
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