SmartWeight — Smarter Skin Weights for Blender Riggers

Bone-proximity prediction with topology-aware diffusion. Detect and fix candy wrapper, volume loss, weight leak. Production-grade weights without the 30-minute manual cleanup.

Why SmartWeight

Blender's built-in automatic weights are a starting point, not a result. Every rigger spends time chasing candy-wrapper deformation at joints, volume loss at shoulders, and weight leak across opposite arms. SmartWeight predicts cleaner weights up front and then detects and fixes the four classic deformation issues so you ship a riggable mesh instead of debugging it.

Features

Predict Weights

• Bone-proximity prediction with edge-diffusion smoothing
• HEAT method with bone-axis falloff
• HYBRID method — proximity + heat combined
• Per-bone prediction for fine-grained control

Issue Detection

• Candy wrapper at parent / child joints
• Volume loss on deforming joints
• Weight leak across body regions
• Asymmetric L / R weights
• Every threshold is derived from the size of your rig, so the same checks work on a 1.8 m character, a 20 m creature and a scene modelled in centimetres — and the panel shows the distance being used

Fix Tools

• Targeted fix operator for each issue type
• Mirror weights L↔R with fuzzy point matching
• Smooth weights with Laplacian + edge-aware falloff
• Auto-normalize to top-N influences (default 4 for game rigs)
• Cleans old weights before writing — no parasitic groups left over

Compatibility

• Blender: 4.2 LTS and later, tested on 4.2, 5.1 and 5.2
• OS: Windows / macOS / Linux
• Rigs: Rigify, Mixamo, Auto-Rig Pro, custom humanoids

What you get

• SmartWeight add-on (Python only, no DLL)
• README with full quick-start guide
• Free updates for v1.x
• Support through marketplace messaging

Install

Edit → Preferences → Add-ons → Install... → pick the downloaded archive → enable. Press N in the 3D Viewport → SmartWeight tab.

License

GPL-3.0. Standard for Blender add-ons.