Import/Export custom vertex attributes (creaseweight)

Hi IStonia,
Do you think you could add handling of creaseweight vertex attribute in imported/exported FBX files? This attribute is used by Houdini to store crease weights of subdivision surfaces. If NVil could read and write it, it would be possible to move crease weights between those two programs.

I'm linking up an archive with FBX files containing crease weights exported from Houdini. It's a simple box with different crease weights {0, 2, 5} applied to its vertices.
https://www.dropbox.com/s/odxrf871g81pikp/creaseweight.tar.gz?dl=1

I ran a diff no_creaseweight.fbx ascii.fbx command, and it seems that the only significant difference between the two, is that the file containing subdivision creases also contains a definition of UserDataArray block with UserData named "creaseweight":

Code: [Select]

208a209,229
>         LayerElementUserData: 0 {
>             Version: 101
>             Name: "UserDataLayer0"
>             MappingInformationType: "ByPolygonVertex"
>             ReferenceInformationType: "Direct"
>             UserDataId: 0
>             UserDataArray:  {
>                 UserDataType: "Float"
>                 UserDataName: "creaseweight"
>                 UserData: *24 {
>                     a: 5,2,2,0,5,0,0,0,5,0,2,2,5,2,2,2,5,5,5,5,2,2,2,0
>                 }
>             }
>         }
>         Layer: 0 {
>             Version: 100
>             LayerElement:  {
>                 Type: "LayerElementUserData"
>                 TypedIndex: 0
>             }
>         }

There are 24 entries in creaseweight array (instead of 8 which you would expect on a six-sided box) probably because Houdini treats vertices differently than points. More info: http://www.tokeru.com/cgwiki/index.php?title=Points_and_Verts_and_Prims

No chance for this to be implemented? 

I use third party dll and there is no way to handle user data.

There are vertex/edge subd-crease information in FBX. Houndini FBX importer/exporter should be upgraded to use those features.

Yeah, I asked about that on SideFX forum around the time of creating this feature request, but never got a response. I'll probably send an inquiry about this subject directly to their support.

I may have found a way. Just allow me some time.

Try this
http://www.digitalfossils.com/Download/NVil-Feb-23-20.rar

Just as a note, this feature was implemented in: NVil-Apr-12-2020.

We can now move creaseweights between NVil and Houdini.