data_utils/README.md

Preprocessed data

We provide the preprocessed data that saved in NPZ files, which contain the following information:

'vertices', 'faces', 'normals', 'joints', 'bones', 'root_index', 'uuid', 'pc_w_norm', 'joint_names', 'skinning_weights_value', 'skinning_weights_rows', 'skinning_weights_cols', 'skinning_weights_shape'

You can check read_npz.py for how to read the NPZ files and save_npz.py for how we save them.

Before saving them into NPZ files, we extract mesh(.obj) and rig(.txt) from downloaded 3D models from Objaverse-XL using Blender. The rig file follows the format in RigNet, which includes the following entries:

joints [joint_name] [x] [y] [z]
root [root_joint_name]
skin [vertex_index] [joints_name1] [skinning_weight1] [joints_name2] [skinning_weight2] ...
hier [parent_joint_name] [child_joint_name]

For an example, please see examples/0a59c5ffa4a1476bac6d540b79947f31.txt.

If you want to convert NPZ file back to OBJ and TXT files, we give an example by running:

python convert_npz_to_mesh_rig.py

Visualization

We provide a method for visualizing 3D models with skeleton using Pyrender, modified from Lab4D. This visualization also serves as input to the VLM for skeleton quality rating. Make sure you have installed the following packages before running visualization:

pip install trimesh opencv-python pyrender

We provide an example to demonstrate the process. For this example, we prepare an OBJ file along with a TXT file containing rigging information. Then, run:

python render_data.py

You will obtain the following outputs:

Reading rig and mesh from GLBs

We provide the script we use for reading rig (.txt) and mesh (.obj) from glb files. You can run:

python read_rig_mesh_from_glb.py

Remember to download Blender (we use 4.2.0) and also bpy in your conda environment.