Hello!! I’m quite inexpert with Rhino and Grasshopper and I’ve been trying to solve this already for two days, I really need help. I’m working with Rhino 6, swapping between Mac and Windows version.
I have a curve that I want to project on a surface, let’s imagine a tridimensional river that flows in a sphere. This was quite easy using the flow along surface command.
But when the surface where the river flows is not a sphere, it gets more complicated. I need this river to flow in the surface of an Icosphere.
I was able to solve this by ExtrudeCrvToPoint, selecting the main curve and choosing the centre of the Icosphere as a target. Then I created a slightly bigger Icosphere and with MeshTrim I was able to obtain what I wanted, great!! (it is actually the same than Boolean Split should do, but somehow it doesn’t work)
I have 15 curves in total to do the same, but there are 3 curves where I cannot do it! I realised that the problem is when the curve, actually not the curve but the extrusion (by ExtrudeToPoint) intersect itself. It was possible for me to do it on the sphere (flow along surface) but I didn’t manage to achieve it for the Icosphere.
One more time, what I need is this big messy curve flowing in the surface of an Icosphere, like a band with constant width.
Thank you for the help in advance!!!
Problem1.gh (205.5 KB)
the icosahedron isn’t a surface - it’s a mesh
thus you need other tweaks - there are multiple ways…
here’s one, to ‘approximate’ your untrimmed surface to the icosahedron, then attempt a mapping:
Problem1_R6.gh (211.9 KB)
Thank you very much for taking time on helping me!!
The picture shows exactly what I want, I will take a look at the GH file that you attached and I’ll try to understand it and apply it on the other curves that I have.
Thank you again and soon I will let you know if it works for what I need!
I’ve been moving forward with my project and your solution works great, thank you!
Do you think it is possible to unfold the Icosphere with the line placed in the right position? I would like to have the pattern of this, 2D in order to later on reproduce it analog. Also it will work if I get a flattened version of each constituting triangle with the lines drawn on it.
I’m already trying out this, but as before, some lines I cannot divide with the Icosphere edges… I tried baking it and applying MeshTrim, Boolean, even extruding the edges of the Icosphere… maybe there is a way in Grasshopper? I have the feeling that it could work somehow how you solved it, through dividing the mapping that you proposed, using the edges of the Icosphere… but I cannot solve it yet…
Any help or clues to help me move forward?
I would like to obtain something in this direction:
Thanks a lot again
I do think it is possible
perhaps you can investigate the MeshMap parameter from Kangaroo:
- find a way to unfold your mesh,
- map stuff (points) from 3D icosahedron to unfolded one,
- rebuild your geometry (curves>surfaces) from there
or, alternatively, you could look into the Ivy plugin
then elaborate from there
Thank you very much!!! I’ll get my head into it, thank you again for your time and input!
