0025774: GCPnts_AbscissaPoint does not work with several bezier curves

View Issue Details [ Jump to Notes ]

[ Issue History ] [ Print ]

Project

Category

View Status

Date Submitted

Last Update

0025774

Community

[OCCT] OCCT:Modeling Data

public

2015-01-30 18:42

2015-01-30 19:58

Reporter

spamkiller

Assigned To

msv

Priority

normal

Severity

minor

Status

new

Resolution

open

Platform

Windows

VC++ 2013

OS Version

64 bit

Product Version

[OCCT] 6.8.0

Target Version

Fixed in Version

Summary

0025774: GCPnts_AbscissaPoint does not work with several bezier curves

Description

I want to distribute points along a bezier curve using GCPnts_AbscissaPoint. But for some curves this does not work.

If you set "offset" to "0.0", only the first point is calculated and displayed (not OK). If you set "offset" to "1.0", all points are calculated and displayed (OK).

For cubic bezier curves it should be possible to set the first two poles to the same point, the same should be possible for the last two poles.

Steps To Reproduce

---snip---
double offset = 0.0;
TColgp_Array1OfPnt poles(1, 4);
poles.SetValue(1, gp_Pnt(0 , 0, 500));
poles.SetValue(2, gp_Pnt(0 + offset, 0, 500));
poles.SetValue(3, gp_Pnt(50.0 - offset, 0, 500));
poles.SetValue(4, gp_Pnt(50 , 0, 500));
Handle(Geom_BezierCurve) curve = new Geom_BezierCurve(poles);
TopoDS_Edge edge = BRepBuilderAPI_MakeEdge(curve);
display(edge);

GeomAdaptor_Curve curveAdaptor(curve);
const double u0 = curve->FirstParameter();
const double un = curve->LastParameter();
const double curveLength = GCPnts_AbscissaPoint::Length(curveAdaptor, u0, un);
const double abscissaStep = 1.0;
double abscissa = 0.0;
double ui = u0;
while (abscissa <= curveLength)
{
     GCPnts_AbscissaPoint ap(curveAdaptor, abscissa, u0, ui);
     ui = ap.Parameter();
     const gp_Pnt & pnt = curveAdaptor.Value(ui);

     display(pnt);

     abscissa += abscissaStep;
}
---snap---
("display" displays an entity in my view)

Additional information
and documentation updates

http://www.opencascade.org/org/forum/thread_26825/?forum=3 [^]

Issue History
Date Modified	Username	Field	Change
2015-01-30 18:42	spamkiller	New Issue
2015-01-30 18:42	spamkiller	Assigned To	=> msv

Relationships

Notes
There are no notes attached to this issue.