Automatic UV Unwrapping
Substance 3D Painter can automatically unwrap meshes that don't have any existing UVs when importing the 3D mesh.
Enabling the Automatic UV Unwrapping
When creating a new project or re-importing a mesh into an existing project, make sure the setting "Auto-unwrap" is checked. If disabled, the process will be skipped and mesh UVs will remain as-is.
This process is not compatible with the UV Tile UDIM Legacy workflow.
UV Unwrapping Settings
When importing a mesh and using the unwrapping process, the following settings are available. Some settings are available via the Options button in the interface.
| Setting | Description |
|---|---|
Seams | Controls if the seams (UV island borders) should be generated only for meshes that don't have them or always regenerated. Possible values:
|
| UV islands | Controls if the UV unwrapping should generated from meshes without UVs or for any meshes. Possible values:
|
| Packing | Controls the packing/layout of UV islands of the meshes. Possible values:
|
| Margin | Defines the spacing between UV islands. This setting applies a general percentage independent from the resolution. Possible values:
|
Known Limitations
Below is a list of limitations related to the unwrapping process:
- Processing high poly meshes can take a long time.
- Vertices at the exact same coordinates are merged
- UV Generation may fail on some mesh parts in some rare cases
- Non uniform or highly distorted texel ratio in a single UV island in some cases
- Non uniform texel ratio between Texture Sets
- UV island generated can be very elongated and do not fit into UV space in some cases
- Degenerated faces or non-triangular mesh faces with small or overlaping edges may not get UV unwrapped
