Project point

Hello! Does anyone know how to project points on curved surfaces? I created auxiliary lines at the required angle, broke them into points and wanted to project these points onto the surface in order to build new lines on them.
I would be grateful for the help.

p1.3dm (156.2 KB)
p1.gh (10.1 KB)

Try Vector->Point->Pull Point.

Yes, I tried to use “pull point”? But this does not work correctly in this case.

Works for me. What were you expecting to see?

p1b.gh (11.6 KB)

I would like to project them smoothly, without shifting to the left to the right, and without missing points

Here’s a potential solution:
p1_HELP.gh (15.3 KB)

1 Like

Unfortunately, I have an earlier version of a grasshopper? But it looks right.

are you on rhino 5 or do you mean earlier rhino 6 release?

Rhino 5 and grasshopper 0.9 lost some components

Could you take a larger picture from the moment of correction?

I tried to restore the chain, but somehow weird

I’m sorry,

the loft wasn’t closed, plus it’s still wacky both in r6 and when I downgraded to r5 - an apology that isn’t a solution

  • looks correct but isn’t
  • additionally I tried helping via a surface offset as a cheat to create vectors between points for ProjectPoint component to work - but right on the turn of the surface where it twists and bends inwards these vectors can’t be kept aligned so eventually point projections still shift to the sides a bit

I installed Rhino 6, now all the components are in place,
but for some reason, some of the points somehow flew away, and when constructing lines, an incorrect connection is obtained

Yes, that’s what I meant, the projections (some) fail in this case (point-far-away situation)

Yes, in any case, thanks!

Have you tried brep closest point?

there’s hope though, if you scale outwards then replicate the line logic you had then you can intersect the original surface to make new curves and make points between outside lines and inside curves - the vectors are now straight - your geometry is still your geometry
p1_HELP2.gh (30.0 KB)

maybe you can play with the rotation of intersecting surfaces to get less wacky vectors

In your first case, LOft creates more correctly.
I mean by new curves

you’re right…I cleaned it up a bit, and went back to BrepClosestPoint as before - some apparent inconsistency when I try to get a curve from the points, but looks correct again and no points flying away:
p1_HELP3b.gh (28.8 KB)

a point never projects,
but if you reduce the lines via ExtendCrv (negative) by something very small then the bug goes away:

1 Like