tranverse through a polygon

j-zhang's picture
j-zhang
Wed, 01/23/2002 - 04:35
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Other usage issues

hello, if i have a polygon, is there any algo. in opencascade to let me tranverse this polygon from a start point to the end point, and find whether a given point is inside this polygon or outside?

thanks in advance.

Francois Lauzon's picture
Francois Lauzon (not verified)
Wed, 01/23/2002 - 17:01

Hi Jimmy,
you might want to look at the Graphics Gems books, there is many algorithm to intersect ray/line with polygon/triangle, or you can build a TopoDS_Shell for your polygon and use the BRepExtrema_ExtCF algorithm for example. But the first method your probably be faster.

Good Luck,
Francois.

j-zhang's picture
j-zhang
Thu, 01/24/2002 - 10:33

Could you kindly explain what is BRepExtrema_ExtCF algorithm ? I cannot find it in
Library book.(I am using opencascade ver. 3.1)

thanks.

Francois Lauzon's picture
Francois Lauzon (not verified)
Thu, 01/24/2002 - 16:45

It's easy to use, look at the BRepExtrema_ExtCF.cdl file, all cdl files are documented.
Good Luck,
Francois.