Get Point Coordinates generated with Geometry Nodes?

Question

Say you generate some random points using Geometry Nodes, how can you get all those point coordinates using the python api?

The only hint I have is that the point coords are located under Point Cloud in the Spreadsheet Editor.

Basically, I want to use those coordinates for scripting other stuff I can't do with Geometry Nodes yet.

Answer 1

This is a workaround and I hope there is (or will eventually be) an easier way to access point cloud data in the API.

In your GN tree add an Instance on Points node, plug in a Mesh Line set to a Count of 1 to get a single vertex at $(0, 0, 0)$.

In theory we should be able to access the vertices' geometry but for now the geometry is not "real". We need to realize the instances with a Realize Instances node.

Then, we need to access the evaluated mesh, after the GN modifier has been evaluated. For that we can use the context dependency graph.

import bpy
import numpy as np

depsgraph = bpy.context.evaluated_depsgraph_get()
obj = bpy.context.active_object.evaluated_get(depsgraph)

coords = np.zeros(len(obj.data.vertices) * 3, dtype=float)
obj.data.vertices.foreach_get("co", coords)

print(coords)  # This is a flattened array

coords = coords.reshape(len(obj.data.vertices), 3)

print(coords)  # This is a 3D array

Result :