Arc-length distance

The curve is known and one point on the curve is also known. Then How to get another point on the curve which keeps a constant arc-length distance(not Euclid distance) with the known point?
Is there anybody who knows how to carry out in OCC?
Thanks a lot.

Bearloga's picture

Hi Jun,
First, project the point to the curve to know its parameter, using GeomAPI_ProjectPointOnCurve. Then you can use GCPnts_AbscissaPoint to measure distances and find parameters along the curve.

Jun WANG's picture

Thanks for the reply. If the known point is in somewhat middle of curve, sometimes there should be two solutions, right? How to get these two solutions? (GCPnts_AbscissaPoint seems to get only one solution.) Thanks again.

Bearloga's picture

AbscissaPoint gives one solution. It is right. You select the side on which to find solution by using the sign of distance (parameter Abscissa).