Rhino3dm: face get mesh always None!

anon39580149 · March 28, 2021, 1:03am

Hello , what is the error in this code? always GetMesh(rh.MeshType.Any) is None.
The file is a simple cube

import rhino3dm as rh

file = "..../cube.3dm"
rf = rh.File3dm.Read(file)

for obj in rf.Objects:
        geo = obj.Geometry
        if geo.ObjectType == rh.ObjectType.Brep:
            faces = geo.Faces
            for i in range(len(faces)):
                print i, faces[i]
                mesh = faces[i].GetMesh(rh.MeshType.Any)
                print mesh

0 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None
1 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None
2 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None
3 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None
4 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None
5 <rhino3dm._rhino3dm.BrepFace object at 0x00000000037E4650>
None

dale · March 28, 2021, 1:16am

If the .3dm file was not saved with render meshes, then there won’t be any meshes to get.

Feel free to post your .3dm file.

– Dale

anon39580149 · March 28, 2021, 5:01am

Thanks , in the simple box file i hit render button than save and the script work fine but with another model and the same method don’t work.
And this wok fine with extrusion unlike faces

if geo.ObjectType == rh.ObjectType.Extrusion: geo.GetMesh(rh.MeshType.Any)

file = "....../test.3dm"
rf = rh.File3dm.Read(file)

for obj in rf.Objects:
    geo = obj.Geometry
    print geo
    if geo.ObjectType == rh.ObjectType.Extrusion:
        #geo.GetMesh(rh.MeshType.Any)
        faces = geo.ToBrep(True).Faces
        for i in range(len(faces)):
            print i, faces[i]
            mesh = faces[i].GetMesh(rh.MeshType.Any)
            print mesh

This is the 3d file:

test.3dm (77.5 KB)

nathanletwory · March 28, 2021, 11:58am

You need to save your file with one viewport in Shaded or Rendered mode.

anon39580149 · March 28, 2021, 12:12pm

Thanks, dont’t wok the same message None

nathanletwory · March 28, 2021, 1:04pm

For an extrusion it is better to directly GetMesh. This is what we do in import_3dm blender add-on as well. I guess creatiing a Brep from the extrusion still doesn’t give you the render meshes, as the brep hasn’t been meshed yet.

github.com

jesterKing/import_3dm/blob/3f171348f3a2216d854108805db28a4a1f61ea42/import_3dm/converters/render_mesh.py#L52


        pass
'''

def import_render_mesh(context, ob, name, scale, options):
    # concatenate all meshes from all (brep) faces,
    # adjust vertex indices for faces accordingly
    # first get all render meshes
    og = ob.Geometry
    oa = ob.Attributes

    if og.ObjectType == r3d.ObjectType.Extrusion:
        msh = [og.GetMesh(r3d.MeshType.Any)]
    elif og.ObjectType == r3d.ObjectType.Mesh:
        msh = [og]
    elif og.ObjectType == r3d.ObjectType.Brep:
        msh = [og.Faces[f].GetMesh(r3d.MeshType.Any) for f in range(len(og.Faces)) if type(og.Faces[f])!=list]
    fidx = 0
    faces = []
    vertices = []
    # now add all faces and vertices to the main lists
    for m in msh:

anon39580149 · March 28, 2021, 2:59pm

Thank you , so import in Blender also need this ?

nathanletwory · March 28, 2021, 5:52pm

Yes.