Mario Veraart (rioj7++at++fel.tno.nl)
Thu, 4 Dec 1997 21:24:21 +0100 (MET)
I have found a small misfunctioning for the pfNode::isect() method.
If I create a simple database consisting of 4 quads at z=0.
The databse is a Multigen Flight file.
Y=
40------------------- Z=0
| | |
| | |
| | |
| | |
0|--------|--------|
| | |
| | |
| | |
| | |
-40-------------------
0 40 80 X=
I want to try to intersect with the following segment
origin = (40,0,-100)
direction = (0,0,-1)
length = 200
I get no intersection with the database.
I use PFTRAV_IS_CULL_FRONT in the mode specifier.
The actual intersection is done for a couple of segments that have
a bounding cylinder set as part of the pfSegSet.
But when I model an extra triangle in the database with coordinates
(36,0,5) (40,0,5) (40,4,5)
I get an intersection hit at location (40,0,5).
Also if I put a quad at z=5 at the same location as the triangle I get
an intersection with this quad.
If I try to intersect along the edge of the (ground) quads
it gives the right result.
I also tried it at location (0,0) and there I got an intersection back.
My question:
Is there a possibility that intersection at an xy coordinate that matches a
vertex coordinate is missed for some of the vertices in a quad or
triangle? (It does not happen along the edge of a primitive)
Mario Veraart
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