Unity Daz to Unity - Vertex count difference

[bigoltacotruck]

I am trying to export just a character (no other assets for now) from Daz3D as an FBX and import into Unity and then apply the blend weights in code using the morph DUF files (this is so that I don't have to export the morphs with every model - I can keep them dynamic and add/remove them as needed in Unity). I have an asset importer working which can read the morph files but the blend doesn't apply to the model correctly as Unity appears to be changing the vertices when it imports the model.

The FBX exporter shows 16,556 vertices which matches what I am seeing in the vertex_count for the morph file:


If I open the FBX in Blender, I can confirm that count:


However Unity appears to be changing the mesh when importing it and the vertex count changes to 18,332


I have tried changing the import settings for the model, such as disabling compression, turning off optimization, checking "keep quads" (just in case), making sure the normals set to import and not calculated etc but I can't seem to get the vertex count to line up!

Here are my model import settings for reference:


I am using Unity 2023.2.9f1 with the HDRP pipeline - any help would be much appreciated as I have hit a dead end.

 

[SpiteWorks - Cassian]

Are you exporting the base resolution from daz? (under parameters)

 

[bigoltacotruck]

Just double checked - set the resolution level to base and sub division to 0 and re-exported. Didn't seem to affect the vertex count for the FBX - still shows at 16,556 in blender (matches DAZ) and 18,332 in unity

 

[60Points]

You can try with "Strict Vertex Data Check". It should maintain the original structure of the file. However, Unity usually corrects vertex issues, and the idea is to leave them as they are imported. There are also other ways to add new blendshapes (comparing delta positions with the original vertex positions), which is a bit more complex but allows you to add blendshapes between slightly different figures, create your own, etc.

 

[SimpleTimes]

my guess is that unity divides the mesh into sections for each material

you could import the fbx to blender, reduce the material slots to one and then import in unity to check if my theory is correct.

(i don't think that this is subdiv related since the vertex count difference is kinda "small", with subdiv you would see a bigger difference)