Forums Technical Discussion How to create an attribute gradient from edge of geo?

How to create an attribute gradient from edge of geo?

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hibatchi
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Hi,

I need to create a per point attribute gradient from the edge of a grid piece of geo to a middle (not necessarily the centroid). Anyone know a good workflow for creating it?
I included a crummy hand drawn image. I'm using a curve/remesh to create round 2d mesh grid, and from there I'm trying to create the per-point attribute for some topology work.

Thanks for any advice

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test_drawing.jpg (56.5 KB)

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Alejandro Echeverry
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You can use a signed distance field (aka sdf) representation of your geometry. That gives you a nice gradient to work with.

You can use the vdb from poligons to convert your geometry, but make sure that its close (water tight).

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Jorge Ivanovich
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2d grid?
Maybe some simple vop node
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hibatchi
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alejandro : Yeah I think the SDF is the way to go. I was experimenting with them, but I'm an ex-Soft guy, and too much of a SDF noob to really utilize them. Can you point me at some material that might explain their use for this kind of problem?

Jorge: I'm in VOPs for the geo already, I just need to bring in an attribute per point, that takes the shape of the round terrain into account. But once I have the “from edge gradient” data, your example is exactly what I'm going to do.

Thanks for the help!
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Alejandro Echeverry
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Here is a very simple example file for you to see two ways of sample a sdf.

I hope that this helps you.

Cheers

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sdf_samples.hip (108.4 KB)

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Jorge Ivanovich
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If the terrain its big maybe you could try with pointclouds it evaluate very fast,here my try

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terrain.hipnc (85.6 KB)

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hibatchi
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Thanks guys! Both methods worked perfectly. Just what I was looking for.

Thanks again
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