extending wire

i need to extend the first and last eddges of an open wire. I don't know which API/Package fit my needs.

Anyone can give me an hint?


Stephane Routelous's picture

I know the function from GeomLib, but it's only for curves : GeomLib::ExtendCurveToPoint

I will compute the intersections of the edges myself ( ex : BRepExtrema_DistShapeShape with creating a new edge to close the wire if no intersection ) and replace the old edges in the wire with the new ones with ShapeBuild_ReShape )



Cauchy Ding's picture

If the edge is related with a face, extend the parameter curve(pcurve, 2d) of the edge, and calculate the 3d curve. Else extend the spatial curve(3d) directly.

Gheorghiu's picture


Can you please explain how can we extend a parameter curve(pcurve, 2d) of an edge? I only need to reach the face boundary wire? What function/class can we use?

Thank you!

Roman Lygin's picture

If you simply need to extend an edge's range along its underlying pcurve you can use BRep_Builder::Range() specifying a face containing a pcurve and a new range. Make sure you also update a 3D curve and other pcurves to preserve the "same range" property (read in this blog post about why it's important).

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