[JAVA3D] AW: [JAVA3D] Bug in triangulating polygons with multiple contours

[Florin Herinean]

Title: Bug in triangulating polygons with multiple contours

Well, it's more or less a bug. The GeometryInfo actualy is not really generating a "planar surface with a hole" but a sort of a mesh. If the "hole" coordinates are not in the same plane, it will create a 3d surface which is not in the plane, but looks more like a triangle strip generated from the two contours. Now what happens if you rotate the hole 180 degrees ? Of course the shape will be corrupted, from your human point of view, but not from the mathematical point. The example below just shows that behavior: the first polygon is facing the positive y axis while the hole is facing the negative y axis. What should the algorithm decide in this case ? It's a distorted shape or a real hole ? How can he decide ?   What does Java3D guys think ?   Cheers,   Florin -----Urspr�ngliche Nachricht----- Von: Dave Smith [mailto:[EMAIL PROTECTED]] Gesendet: Freitag, 10. Januar 2003 17:14 An: [EMAIL PROTECTED] Betreff: Re: [JAVA3D] Bug in triangulating polygons with multiple contours I'm surprised such a simple example doesn't work.  I even reduced the noise and made everything planar.    Looks like a bug to me.   -DaveS   ps.  Used same setup pps.  Here is the modified data:   Point3d[] coordinates = {                 //outer bounds of the polygon                 new Point3d(2., 0.0, 0.0),                 new Point3d(2., 0.0, 1.3),                 new Point3d(0.0, 0.0, 1.3),                 new Point3d(0.0, 0.0, 0.0),                   //the hole                 new Point3d(1.93, 0.0, 0.07),                 new Point3d(0.07, 0.0, 0.07),                 new Point3d(0.07, 0.0, 1.13),                 new Point3d(1.93, 0.0, 1.13)                 }; ----- Original Message ----- From: Tero Karhunen To: [EMAIL PROTECTED] Sent: Friday, January 10, 2003 8:33 AM Subject: [JAVA3D] Bug in triangulating polygons with multiple contours It seems that sometimes when i attempt to use GeometryInfo by specifying polygons with holes, the triangulated results aren't correct. The test method attached can duplicate this, it only creates a Shape3D however, since even a minimal program to display and maybe rotate the view requires a bit of work. I hope you guys can plug it into something you already have to confirm this. I have had these results with java3d v1.3 on win2000 platform. -tero