Color mesh with per-vertex values in Blender 4.2 using Geometry Nodes

Following my banger of a post from 2022 lets revisit the same problem in 2026: now in Blender 4.2.3 (LTS).

Here I show a better way to solve the same problem: color mesh with per-vertex values, this time more interactive and with Geometry Nodes.

Load values

Here is a simple script to populate named attribute with random values:

import bpy
import random

mesh = bpy.data.meshes["cow"]

attribute = mesh.attributes.new(name="eigenvector", type='FLOAT', domain='POINT')

for i in range(len(mesh.vertices)):
    attribute.data[i].value = random.uniform(0.0, 1.0)

Map values to color

The magic happens in Geometry nodes:

Here we map vertex float attribute eigenvector to a vertex color attribute eigencolor.

• We first normalize values to 0-1 with Map Range
  • Maximum node (comes in Utilities/Math) helps with mapping
• Then value is mapped to color using Color Ramp
  • Color ramp can create any gradient, and you see the results immediately

Setup shader

The shader is very simple: use vertex color attribute eigencolor

Done! Go have fun with the Color Ramp and see the results immediately.