section through surface is not producing continuous, closed curves - why?

I have a surface which has been generated from a grid of points - these came from the ends of curves - and I am experiencing a problem that seems inexplicable. My section plane is not giving me continuous curves, here and there there are gaps along its length.

I find that if I push the plane closer to the peaks, or max z values of the surface, the problem goes away - but I need to slice through this surface to its minimum z values...

I've attached an image which might give you a sense of what I'm talking about...

help? thanks!

Replies to This Discussion

Permalink Reply by Gabriel on May 25, 2009 at 9:50am

Permalink Reply by David Rutten on May 25, 2009 at 10:44am

Hi Gabriel,

not sure what's going on, can you mail me all the files I need to reproduce this?

( david@mcneel.com )

Permalink Reply by David Rutten on May 25, 2009 at 12:31pm

Hi Gabriel,

Both the surface and the cutting plane are very big objects for your tolerances, but worse, the surface you are intersecting is very, very flat. If you bake the geometry and perform the same intersection in Rhino using the _Intersect command you get the exact same result.

This is clearly a bug in the Rhino intersector. Perhaps if you were to scale your geometry into the z-direction (say a factor of a 100) the intersection would work better...

RSS