Apply polyLines to surface?

Is there a simple way to translate 2D polylines onto a 3D double curved surface?

Basically, the Y height of the 2D curves needs to correspond directly with the Z world height starting at the bottom of the surface but the X values of the 2D curves correspond to the horizontal point along the surface.

I tried using UV points to analyze the surface and the curves and then translate the curves to the surface which seem to work with 2 curves however once I add more curves (250+ which actually need to be polylines, not curves) it's so overcomplicated to find all the intersection points etc... that it doesn't seem like the best solution. Plus, it's not 100% accurate.

There must be a way such as draw interpolatedCurveOnSurface but with polylines that would work. Anyone have any ideas?

Attachments:

crv_on_srf.jpg, 1.4 MB

Replies to This Discussion

Permalink Reply by Elizabeth Tweedale on August 20, 2009 at 5:48am

Have attached the grasshopper and rhino files as well.

Attachments:

crv_on_srf.3dm, 66 KB
crv_on_srf.ghx, 881 KB

Permalink Reply by taz on August 20, 2009 at 6:05pm

Elizabeth,

The attached definition should work with your rhino file.

You can create a reference surface in the plane of your curve and transcribe uv coordinates from the reference surface to the target surface. Then you can use the Curve on Surface component. I'm not sure how this would work with polylines. It would depend on what you want the final result to look like.

-taz

Attachments:

ONE crv_on_srf.ghx, 111 KB

Permalink Reply by taz on August 20, 2009 at 7:01pm

Parting thought:

You could use this approach with a polyline but you would have to rebuild it from a resulting curve on surface. This would give you straight segments with points that intersect the target surface. I'm not sure if that's what you're looking for.

-taz