How to get parameter for a point on the curve

Gieldu Mistrz's picture
Gieldu Mistrz
Sun, 11/01/2020 - 19:10
Forums: 
Modeling Data and Algorithms

Dear Friends.

Geom2d_Curve class has method Value computing the point of parameter U:

gp_Pnt2d Geom2d_Curve::Value ( const Standard_Real  U ) const

 

I would like to do the opposite operation: having the point on the curve and I would like to get the value of the parameter. 

How to do that?

Thanks in advance.

Regards,

Janusz

Gianluca Antoniacci's picture
Gianluca Antoniacci
Tue, 03/16/2021 - 17:16

Hello Janusz,

normally this goal is achieved by projecting the point onto the curve and taking the projection parameter onto the curve. Have a look at the class GeomAPI_ProjectPointOnCurve.

With particular curves, sometimes, you can use the method ElCLib::Parameter() to get the parameter associated to the given point.

Best regards.

Gianluca