Tue, 06/30/2009 - 17:49
Forums:
... as the subject says I want to get a point on a wire by length - tried everything but I see no way to do so. Using the parametric values also doesn´t help... someone an idea???
Thanks - Stefan
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Tue, 06/30/2009 - 18:04
BRepAdaptor_CompCurve is the solution.See code below :
BRepAdaptor_CompCurve aCompoundCurve(TopoDS::Wire(aRailSh), Standard_True);
"then"
aCompoundCurve.D0( parm, aPnt );
should give the point in space.
Fotis
Tue, 06/30/2009 - 18:12
I had problems with doing it like that
I had to do my own "BRepAdaptor_CompCurve" and using recursive code to have a correct result, as using the code as you mentionned was producing a point at a bad distance (accuracy issue).
Stephane
Tue, 06/30/2009 - 18:14
Ahhhh.... and I thought it´s something "easy".
Tue, 06/30/2009 - 18:18
well, it's supposed to be easy..
the "easy" way is to use GCPnts_AbscissaPoint
but as i said, it gave me incorrect results. you can still test with your wires/curves to see if it works for you.
Stephane
Tue, 06/30/2009 - 18:36
Hmmm... yeah the problem is that I have to use the length to find the point... (it´s some kind of strange transformation and it will only work correct when I take the length). Finding a point by length doesn´t seems to be supported. And an recursive alg. could be very time consuming.
damn....
Tue, 06/30/2009 - 18:45
> And an recursive alg. could be very time consuming.
no it's quite fast (at least fast enough for my cases)
Stéphane
Tue, 06/30/2009 - 19:05
yeah... u say the algorithm is quite good. Can I see it. ;)
Tue, 06/30/2009 - 19:12
Ok.... it took me some time to check out what the second parameter means... thanks i will give it a try!!!