3d particle shader with randomly sampled areas of a mesh on the screen

Godot Version

4.3

Question

i’m looking into creating a “destruction” particle effect that would be some simple 3d planes falling, but the trick is their texture would be a randomly sampled area of an object visible on the screen
kind of difficult to explain with words so here is the thought process:

in other words it takes in a viewport from the camera, removes everything but the object, takes resulting image and splits it into random areas of the image (pieces) as a gpu particle

i dont really know where to start with this or if this is even possible in godot so i’m looking for some advise