Sagan Bugs & Feature Requests

josiahmora20

First of all, I wanted thank you for making such an awesome plugin! It's going to save me tons of time in the long run. The following are bugs to fix and features that would make it even better.

 

1. Unnecessary Geograft Meshes

When you import the Alembic file into Blender, the geografts will combine with the mesh but also be added as extra, separate meshes. Deleting these causes no issues, as they just seem unnecessary.

 

2. Vertex Mismatch & Streched Uvs

Regarding the character's main body mesh (with the combined geoshells), there seems to be a bug with how vertices are being calculated. Comparing the seemingly identical mesh from Diffeomorphic, the Sagan import has 399 fewer vertices, which I initially thought was due to how the geografts were being merged in Diffeo. However, when you link object data between a Diffeo body mesh and an Alembic body mesh, suddenly the vertex count is the same. Copying object data doesn't work if mats have nomal maps, uv maps/udim tiles, it will show they transfered over but the materials can't use them for some reason. 

 

3. Hair Seperate By Mats

Unlike Diffeo's imported mesh, you can't go into edit mode and use CTRL+P to split by material. For some reason, doing this just copies the hair mesh for each material that exists.

 

4. Scale Issue

So i've been exporting my character with it's default scale which tends to reset after I apply a pose (because I choose not to bake transforms on my character (in daz)). Her default scale for some reason is 99.4 not 100%. The scale resets a lot when applying certain pose presets (probably because I'm using full body and proportion morphs, not sure though). The scale that I WANT to use and have been using is 89.46%. When I noticed her scale was reset to 99.4% after I loaded a pose preset I reset it to 89.46% and followed the same steps I had been to export with diffeo and then export with Sagan and link object data in Blender, but then the mats Uvs are streched and in the incorrect places. So I went back and set the scale to 100% and got the same issue. But then if I ALT click the scale in Daz so it defaults back to 99.4% and export, everything works.​ 

 

5. Support for Hair Curves

Hair cards are fine until you realize your render is going to require 35 transparent light bounces and take 5 hours to render. Blender's new hair curves are an excellent alternative, and Diffeo's "Make Hair" option is fantastic for achieving this. However, the problem with the Alembic import is that once hair cards are converted to hair curves, they don't follow the Alembic animation. Since Alembic requires the "Mesh Sequence Modifier" for all animation data, hair curves are left out because no such modifier exists for curves. I've tried using geo-nodes to attach hair to the surface, parenting in every way imaginable, using constraints, and nothing seems to work. Aditionally, when adding quick fur to the Alembic character some hairs do not attach to the surface (Via Surface Deform geo-node). Someone had previeusly suggested that this was an issue with hairs being placed on or very close to a UV seam.