Findin global vertex coordinates

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Allen Bierbaum (allenb++at++icemt.iastate.edu)
Fri, 5 Apr 1996 15:59:40 -0600

Here is my problem,
         
        I have a triangle in a geoset. I want to shoot rays out of the center of the triangle in a hemispherical pattern, in order to see what polygons the triangle can "see". To do this I find the center of the triangle and the triangle's normal, and then construct a set of segments form this information. The problem is that I am intersecting the segments with the whole scene graph, so since my triangle is below some DCS's, the center point in the global coordinate system (at the root node) is different than my value. Because of this, the intersection is being passed the wrong values. I believe that I need to transform the segments into the global coordinate system before the intersection.

        1. Am I correct in my assessment of the problem???
2. How do I solve this problem??? (I know that I have to find the transform matrix up to the triangle, but then do I multiply my segments by that matrix, or it's inverse)
3. How do I find this matrix knowing only the geoset the triangle is in??? (I can guarantee that geosets are not shared)

Thanks in advance for any help

-Allen

==============================
Allen Bierbaum ISU Vislab - ISU CAVE
allenb++at++iastate.edu
RA - Carolina Cruz
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