How to compress a obj file? about dracopy HOT 5 CLOSED

Hi Johnathan,

The main problem is the mesh is currently in OBJ form which is a text stream describing the mesh. It needs to be decoded into numpy arrays of vertices and faces. Luckily, we provide some libraries that may help (though they support only a subset of the OBJ format).

zmesh comes with a zmesh.Mesh class that has a mesh = Mesh.from_obj(txt) function. We also provide a similar mesh class with more lenient licensing in cloud-volume. This will yield a decoded mesh object that has mesh.vertices and mesh.faces. You can then proceed to use DracoPy. Here's an example:

import zmesh
import DracoPy

with open(os.path.join(testdata_directory, "bunny.obj"), "rt") as improper_file: 
    file_content = improper_file.read() 

mesh = zmesh.Mesh.from_obj(file_content)
draco_binary = DracoPy.encode_mesh_to_buffer(mesh.vertices.flatten('C'), mesh.faces.flatten('C'))

There are probably several other libraries you could use to convert the obj to raw vertices too.

from dracopy.

Arguably, we should have an obj reader in this library too to make this operation easier.

from dracopy.

thanks for your reply dude !
I use your example in my project:

drc_file = open("testdata_files/head3d.drc", "wb")
with open("testdata_files/head3d.obj", "rt") as improper_file:
    file_content = improper_file.read()
    mesh = zmesh.Mesh.from_obj(file_content)
    draco_binary = DracoPy.encode_mesh_to_buffer(mesh.vertices.flatten('C'), mesh.faces.flatten('C'))
    drc_file.write(draco_binary)
    drc_file.close()

but error

Traceback (most recent call last):
  File "compressDraco.py", line 33, in <module>
    compress_obj_to_draco()
  File "compressDraco.py", line 27, in compress_obj_to_draco
    mesh = zmesh.Mesh.from_obj(file_content)
  File "C:\ProgramData\Anaconda3\envs\py37\lib\site-packages\zmesh\mesh.py", line 136, in from_obj
    (n1, n2, n3) = re.match(r'vn\s+([-\d\.]+)\s+([-\d\.]+)\s+([-\d\.]+)', line).groups()
AttributeError: 'NoneType' object has no attribute 'groups'

How to solve this problem?

from dracopy.

It seems the regexp I wrote does not match the format of the vertex normals line in your OBJ file. You can try looking at other OBJ parsers that might be more complete (the one I wrote is very simple). Another possibility is that your OBJ file is malformed, but I wouldn't bet on that unless other OBJ parsers fail on it. If you can share the OBJ, I could try it myself and see if the behavior is reasonable.

from dracopy.

Closing due to inactivity. Let me know if you still need help.

from dracopy.