numpy random state varies after PR2() is called

[HiroIshida]

As PR2() function is supposed to behave deterministically, the hash value of the random state should not change.

import hashlib
import pickle
import numpy as np
from skrobot.models.pr2 import PR2

for _ in range(4):
    pr2 = PR2()
    print(f"hash {hashlib.sha256(pickle.dumps(np.random.get_state())).hexdigest()}")

However, ...

h-ishida@azarashi:~/Dropbox/paper_writing/tro2024/benchmark2/moving_pr2_minifridge_sqp$ python3 hoge.py 
/home/h-ishida/python/scikit-robot/skrobot/model/robot_model.py:1721: UserWarning: texture specified in URDF is not supported
  warnings.warn(
hash 2024fb2f4db1d7ebdd72ab0628173e117c33d60eb6f916a2ce3de6536abc2832
hash 123437b8a64fbfc1dba8c82135f36f59fcd3bc4e76131a62e28871063905bc28
hash cc0aa4612ae4d9feebe20f6d912fa0d92e607fe228ab91e8853a70ee053f837d
hash 05924ab4d0eedc50dfd60e50d7c99f7aa8e12bec054651eb64740847eb848f31

Inserting hash evaluation snippets inside skrobot's urdf parsing part, I found that trimesh smells.

Yes, trimesh.apply_transform seemingly change the random state

Found it. This is called by mesh.apply_transform.
https://github.com/mikedh/trimesh/blob/b9f82a52d4f804220cb8829872dea9ba04fd6f82/trimesh/transformations.py#L2290