One way of doing it is using Voronoi diagrams.
Coding this stuff is pretty complicated.
If you're looking for something simpler
maybe using
(vlax-curve-getSecondDeriv curve-obj param)
at each vertex to get the tangent vector
and then running a perpendicular vector
from the tangent with the desired distance
you'll get the points to draw the offset
polyline.
I believe your "ray" approach will not work
cause rays from the mass center to the polyline
are not perpendicular to the polyline at all points.
The offset polyline is the intersection of a plane
at your offset distance, and a solid extruded from
your original polyline at a 45 degree angle.
--
Saludos, Ing. Jorge Jimenez, SICAD S.A., Costa Rica
"FrozenLips" wrote in message
news:23893267.1107812450086.JavaMail.jive@jiveforum1.autodesk.com...
> Yup, you got it right.
>
> The only reasonable mathematical solution I had found for it was the
> following:
> (Though it IS discreet)
>
> - find the center of the mass of the inner polyline using integrals
> - from it build a polar array of rays
> - using the intersections of the rays and the polylines, some
> approximation of the needed polyline can be created.
>
> Ofcourse, the more rays we send, the more approximate we get.
>
> And yet this solution may not work well with complex topographies......
> (Think about a U shaped inner polyline inside of a circle shaped polyline)
>
> Anyhoops, this is the best I cold think about (Without getting down to
> linear Algebra stuff :)
>
> tata,
> lata,
> Elizabeth
