(geometry nodes) curve based crossing decals?

[TM1988]

The idea is to create a decal system with intersections (crossing).
The problem is the overlapping profiles.

This is my approach, you draw a curve on a surface (intersection would be nice but for the sake of simplicity, the overlaps would only have to be at nodes).

Then you would have to outline the curve. The large distance is only for better clarity.

This is what it would look like with a curve profile.

This is what it should look like, just with adjusted corners.

The texture could be implemented either with normal maps or with bump maps (looks a bit washed out and could be better).

I’m just a geometry nodes beginner and it’s often beyond my horizon :).
Maybe these implementation ideas can help.

pathway intersections manipulation in blender's geometry nodes

creating intersection points along the intersecting parts of two splines# geometry nodes

[sozap]

Hello !

The curve intersection algorithm you find out seems promising !
Once that’s solved there is still the mesh generation that looks tricky too !

Maybe someone would find time and interest to dig into that problem, to me this looks like something that might takes one or two day of testing to maybe ending up in a dead end…

But that’s just my instinct maybe someone else might find a simple way to solve the issue or I might be missing something.

Anyway, if your goal is to master GN and solve these kind of problem on your own then you might consider doing simpler exercise within your reach.
If your goal is having someone figuring out the thing for you, then it looks more like some kind of volunteer job to me.

This wouldn’t be an issue if that’s something someone could solve in less than an hour, as it’s the case with many successful GN related post on this forum.
Unfortunately it doesn’t seems the case to me on this one. Anyway this looks interesting and challenging so maybe someone will take that as a learning opportunity…

[TM1988]

Thank you for your detailed answer and your assessment/feedback.

[TM1988]

If anyone is interested, here are a few updates

These node groups are not mine

(Geonodes)Align Curve Tilt to Normal?

Is there a reliable way to align curve bevel profile to a normal of a given mesh’s surface? I couldn’t manage it using Set Curve Tilt [image]

How do I get the coordinate where an edge intersects a face using geometry nodes?

[TM1988]

The next step is to use the detector points to subdivide the edges nearby and then move them towards the detector points (vertex slide) to merge them. Now you can separate the vertecies with more than 2 edges (delete the inner intersecting edges) and you would have outlines.
GN_decal_system.blend (174.2 KB)