Looping with Vlax-Curve-GetPointAtDist

[Lee Mac]

I seem to be having a problem with splines when using vlax-curve-GetPointAtDist, as it doesn't ever return nil when it has reached the end of the spline - it will just return a constant point which lies some way off the spline.

 

I wondered if anyone else suffered with this issue? And if they found a way to fix it?

 

My question is in reference to this thread:

 

http://www.cadtutor.net/forum/showthread.php?t=35741

 

 

I had to use a work-around which was far from ideal...

 

Cheers

 

Lee

[Lee Mac]

Has no-one else ever encountered this issue?

[CAB]

Perhaps a test to prevent this incorrect distance?

(setq MaxDist (vlax-curve-getdistatparam curve-obj (vlax-curve-getendparam curve-obj)))

 

(<loop>
 (if (<= Dist MaxDist)
    (<do your thing>)

 

 

BTW how are you getting the color codeing in your posted code?

I seem to remember a post about that but my memory is going.

[Lee Mac]

Perhaps a test to prevent this incorrect distance?

(setq MaxDist (vlax-curve-getdistatparam curve-obj (vlax-curve-getendparam curve-obj)))

(<loop>
 (if (<= Dist MaxDist)
    (<do your thing>)

 

Thanks CAB, I resorted to a test similar to this in fact - but I just wondered why the function would throw up such an error, and keep the loop. - But I suppose its just the stubbornness of Splines.

 

BTW how are you getting the color codeing in your posted code?

I seem to remember a post about that but my memory is going.

 

I have modified a LISP posted on here ages ago by David Bethel to incorporate VLIDE colours and add the required tags to the code before posting

[CAB]

Yes I have experienced the same problem but don't remember which routine I it was that needed corrective code. It would take some research to dig it up so I posted what I remembered as the fix.

 

That too is how I remember it but I can't find the COLOR lisp by David. I'm sure I would have saved it. What is the defun c: ?

[Lee Mac]

I could email the code to you if you wish?

[CAB]

Yes, please do so.

Thanks