I am not sure I completely understand your question. I assume you are trying to get the parametric coordinates of a point in 3-D space with respect to a particular face. If you are looking for the coords of a vertex, look at BRepTool::Parameters. It takes a vertex and a face and returns the parametric point. If you are looking for the coords of a generic point, use GeomAPI_ProjectPointOnSurf to project the point on the surface of the face and get the parameters with the LowerDistanceParameters parameters function.
If you are trying to go the other way and get the 3D point from the parameters, use BRepLProp_SLProps.
Wed, 06/22/2005 - 18:00
Hello,
If you have a TopoDS_Face object , use the class BRepLProp_SLProps.
Otherwise if you have a Geom_Surface object, use the class GeomLProp_SLProps.
Wed, 06/22/2005 - 18:03
I am not sure I completely understand your question. I assume you are trying to get the parametric coordinates of a point in 3-D space with respect to a particular face. If you are looking for the coords of a vertex, look at BRepTool::Parameters. It takes a vertex and a face and returns the parametric point. If you are looking for the coords of a generic point, use GeomAPI_ProjectPointOnSurf to project the point on the surface of the face and get the parameters with the LowerDistanceParameters parameters function.
If you are trying to go the other way and get the 3D point from the parameters, use BRepLProp_SLProps.