Extra formats

[clbarnes]

• [ ] Neuroglancer (binary)
• [x] Wavefront OBJ (text)
• [ ] TIN / Polyhedral surface EWKT?

[clbarnes]

def write_obj(path, mesh):
    vertex_fmt = "v {} {} {}\n"
    face_fmt = "f {} {} {}\n"
    with open(path, "w") as f:
        for vertex in mesh.points:
            f.write(vertex_fmt.format(*vertex))
        for face in mesh.cells["triangle"]:
            f.write(face_fmt.format(*(face + 1))) # 1-based indexing

def read_obj(path):
    points = []
    triangles = []
    with open(path) as f:
        for row in f:
            if row.startswith("v "):
                points.append([float(item) for item in row.split()[1:]])
            elif row.startswith("f "):
                triangles.append([int(item.split('/')[0]) for item in row.split()[1:]])

    return Mesh(np.array(points), {"triangle": np.array(triangles)})