Check out Blender 4.3’s new SLIM UV unwrapping system
UV layouts generated from a 3D model of a human head by Blender’s existing Conformal method and the new SLIM algorithm. Areas of UV distortion are shown in orange and red.
Blender just got support for SLIM, a “state-of-the-art” iterative UV unwrapping algorithm.
The algorithm, implemented in alpha builds of Blender 4.3, unwraps complex meshes with less distortion than existing options,
The work was originally begun eight years ago, but has just been completed by Łukasz Czyż, developer of the UVPackmaster UV unwrapping plugin for Blender.
Less distortion and more controllable results than existing UV unwrapping algorithms
Developed by researchers at ETH Zurich, SLIM (Scalable Local Injective Mappings) is an iterative method for UV unwrapping meshes.
As well as providing good results on complex meshes, even those with no UV seams defined, setting iterations lets users trade the quality of the UV maps generated against processing time.
Work on integrating SLIM into Blender originally began eight years ago, while Blender 2.7 was in development.
Although the project initially stalled, Łukasz Czyż has now picked up where original developer Aurel Gruber left off, and the code was merged into the main branch of Blender this week.
In alpha builds of Blender 4.3, SLIM is available via the Minimum Stretch option in the UI.
In this blog post, you can see comparisons of the UV distortion it creates when unwrapping a 3D model of human head, relative to the existing Angle Based and Conformal options.
According to Czyż, SLIM can also be used to reduce stretching on meshes that have already been unwrapped.
System requirements
SLIM UV unwrapping is available in Blender 4.3. It is currently in alpha, with the stable release due in November.
Blender is compatible with Windows 8.1+, macOS 11.2+ and glibc 2.28+ Linux. It’s free.
Read more about integration SLIM into Blender on Łukasz Czyż’s blog
Download daily alpha builds of Blender
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