Okay, after looking at your definition, I take back all of the stuff that I wrote above because its none of that. Your issue is how you're actually creating the polylines themselves. All the points are fine, but the problem is that you're supplying the start and end points twice and then closing off the polyline. This means that there's actually a line segment between two coincident points in your polyline. This is what's causing the problem when projected.
The solution is to remove those extra points, so that the polyline is better structured. To do this I just trimmed off the last element in the list for points that made each polyline. After that, it worked as expected. As a general note, sometimes its helpful to use Rhino to find where potential issues might be. Basically if you bake something, try it in Rhino, and it still fails, then its most likely an issue with the geometry itself rather than the given operation. If Rhino can do it and GH can't, then there might be more of an issue. Also, having the geometry within Rhino allows for more manual inspection. I probably wouldn't have been able to find this if I hadn't baked it in Rhino, tested if project worked, then looked closer at the geometry itself. Just some useful points next time you run into something. Best, Damien On Apr 13, 10:31 am, damien_alomar <[email protected]> wrote: > I think your issue might be with the geometry that you're trying to > project the curves onto. There are maybe a few things I would try. > First I would try scaling up the geometry, since the curves look like > they might lie just off the edge. Second I would actually extrude the > curves with the same projection vector through the surface and see > what the intersection curves end up like. > > Best, > Damien > > On Apr 12, 10:04 am, Grandtour <[email protected]> wrote: > > > look at this picture which is more clear(http:// > > grasshopper3d.googlegroups.com/web/Snap60%E5%89%AF%E6%9C%AC.jpg? > > hl=en&gda=VtqwOE4AAAC19Ve3i4OoV9kZmG4Q4mscNIkyP- > > tCUghW1QuVVlVA61YqcskqebAbKftsofvUXEUn7qXJT5AHaveIBVLZAuxz47Cl1bPl-23V2XOW7kn5sQ&gsc=qfXejhYAAADUzyauo2L8w- > > tO_BGKbWcFaKk2tFLs90LD5qOQGCC3Kw)
