Geometry Nodes: Random per Object (per Modifier) - Randomize a Noise Pattern

Question

Using the Noise Texture node in Geometry Nodes, how do you set it up so that the pattern is randomized with each use of the Modifier?

There is no 'seed' input for Noise, and adding a Random Value node to the W-input doesn't work as expected (I posted about that here).

Any suggestions?

Answer 1

A simple solution

The simple solution assumes objects don't move and you never have objects with same location (or you're fine with them synchronizing the random values in such case):

If you want to be able to move those objects without rerandomization (for animation purposes), you could use a Simulation Zone:

XY's solution

random_type = 0 
"""
random_type = 0 - same behavior as "Random per Object" in shaders, value depends on object name
random_type = 1 - as above but multiple modifiers on the same object 
random_type = 2 - the script randomizes different numbers for the same object each time it is run
"""
from bpy import context as C, data as D
from random import seed, randint
randomizer = D.node_groups['Randomizer']
input_id = next(i.identifier for i in randomizer.inputs if i.name == 'Seed')
for ob in C.selected_objects:
    if random_type == 1:
        seed(ob.name)
    mods = (m for m in ob.modifiers if m.node_group == randomizer)
    for mod in mods:
        if random_type == 0:
            seed(ob.name)
        random = randint(-231, 231-1)
        mod[input_id] = random
    ob.data.update()

• Random Value node is there, because Noise Texture's $W$ dimension is limited to $-1000...+1000$ range [it isn't! Only the interface limits the input in that range; Learned it thanks to folks on Discord]; the code could be modified to generate a random float in that range, but this way randomizing seeds is decoupled from the node trees using those seeds.
• The script has to be run each time you add a new object, and - if you want the seeds to be synchronized with object names - each time you rename an object.
• You need to select all relevant objects before running the script but that could be trivially changed if needed…
• Notice how I usually don't screenshot a node tree name, but in this case I did because that's how the script discriminates the correct modifiers: there could be Geonodes modifiers with a seed input that is not supposed to be randomized.