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What I'm trying to do in blender 2.93.1: Animate a VertexWeightProximity effect (geometry nodes distributed/instanced cubes on mesh going away as empty gets near) while also animating the main mesh becoming less blocky (via animating remesh octree depth).

Problem: The Remesh modifier won't allow the VertexWeightProximity effect to happen.

General Setup with Remesh enabled and proximity not working

When the Remesh modifier is disabled the proximity effect works as expected, but this won't allow me to animate the remesh change happening at the same time. General Setup with Remesh disabled and proximity effect working

I've tried changing the modifier order and other basic stuff (I'm fairly inexperienced with Blender) but nothing seems to work. Anyone have a suggestion?

Thank you

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The Remesh modifier destroys vertex groups on the mesh, rendering the Vertex Weight Proximity modifier useless in that case. Thankfully there is a built-in Attribute Proximity node that you can use in the GN modifier.

It only works with Geometry though, so instead of an Empty object, you'll have to use a small mesh object, like a scaled down cube. Make sure to set the node to "Relative" or else it won't react when you move the falloff object.

enter image description here

Place the GN modifier after the remesh :

enter image description here

Result :

enter image description here

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  • $\begingroup$ You did not hide the original Suzanne object?!😳😳😱😱I am a bit disappointed….but…ok…+1 $\endgroup$
    – Chris
    Jul 5 at 12:21
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    $\begingroup$ @Chris Ups... Consider that as a backstage tour :) $\endgroup$
    – Gorgious
    Jul 5 at 12:22
  • $\begingroup$ This is good, but if they wanted to use the empty, they could also use a vertex weight edit modifier to assign all remeshed vertices to the proximity VG, between remeshing and checking prox. $\endgroup$
    – Nathan
    Jul 5 at 16:06
  • $\begingroup$ @Nathan In my experience the VW proximity modifier doesn't work if the mesh doesn't contain already initialized weights... It may be a bug but I never bothered bringing it up to see if it's a feature ^^ $\endgroup$
    – Gorgious
    Jul 5 at 21:09
  • $\begingroup$ I'll show you how to re-initialize weights with vertex weight edit below. $\endgroup$
    – Nathan
    Jul 5 at 21:52
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As mentioned by Gorgious, remesh destroys the existing groups. (There are a number of other situations that do this too; booleans are a good example.)

But for prox, you don't need any particular weights, you just need the weights to exist, and you can initialize them with a vertex weight edit modifier, after the remesh:

enter image description here

Notice what the vertex weight edit is doing. First, I'm using a custom curve that just assigns everything to my proximity group. Second, I'm enabling "Group Add" which will add vertices to that group, even if they weren't in that group. By doing this, I can assign all generated vertices to this group, which then lets me run a proximity on it, which then lets me run geo nodes on it.

There's nothing wrong with what Gorgious is offering; this is just an alternative.

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  • $\begingroup$ Thank you Nathan for an alternate solution. I haven't tried it out yet as the marked solution above was a quick solid fix - but I'll try this one out for fun when I have time. $\endgroup$ Jul 6 at 0:10
  • $\begingroup$ Oh, nice ! Thanks for the explanation :) $\endgroup$
    – Gorgious
    Jul 6 at 6:37

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