Auto Fit & Shrink — Clothing Bind & Body Shape Keys — Blender Add-on (Beta)

Auto Fit & Shrink — by Lapinouu

Bind an already fitted garment and create an adjustable body shrink shape key in one workflow.

Built for avatar creators working in Blender, Auto Fit & Shrink combines surface weight transfer, armature binding and body thinning beneath clothing. Keep control over the result with a separate Shrink_<garment> shape key on the body.

WHAT YOU GET

• Bind & Shrink: transfer weights, attach the garment to the body's armature and generate its body shrink key.

• Transfer Weights Only and Generate Shrink Only for independent adjustments.

• Surface Retreat for gentle inward offsets.

• Bone Axis Shrink for stronger thinning inside covered areas.

• Automatic coverage estimation, opening margin, edge falloff and editable coverage masks.

• Select Unresolved and diagnostic reports to inspect failed weight matches.

• English interface, tooltips and guide. Runs locally without extra dependencies or online activation.

QUICK START

1. Fit your garment to the body in rest pose.

2. Select Body and Garment in the AutoFit sidebar.

3. Choose a shrink mode and start with conservative settings.

4. Run Bind & Shrink, then inspect the result in poses.

5. Adjust the body's Shrink_<garment> slider.

UNITY / VRCHAT WORKFLOW

The body shrink shape key is intended for export as a blendshape. Configure your clothing toggle in Unity to set the corresponding body blendshape to 100 when worn and 0 when hidden. Toggle setup and export are manual; this beta does not automate or validate the Unity pipeline.

REQUIREMENTS

Blender 4.2 minimum. Validation performed on Blender 4.2.0, with separate transfer-fix tests on 4.4.3.

A body with an Armature modifier and usable deform-bone weights.

An already fitted garment. One body and one garment per operation.

Use a prepared copy: non-Armature modifiers must be disabled in both viewport and render. See the included guide for supported morphology and transform settings.

BETA 0.1.1 — PLEASE READ

This is a workflow helper, not a universal automatic fitting or collision solver. It does not resize clothing to a different avatar, transfer the body's other morphology shape keys, simulate cloth or delete polygons.

Some garments require manual weight or coverage adjustments.

Check your intended poses, morphs and garment openings before production use. Shrinking geometry alone does not reduce polygon count or improve VRChat performance rank.

DOWNLOAD CONTENTS

Version 0.1.1 English edition: Blender extension files, English README, Python source, license and test scripts/reports. Jinxxy hosts the files individually. Download all files and follow the purchase note to use or assemble the ZIP required by Blender.

No avatar, clothing mesh, textures or demonstration scene is included.

Cover image: AI-generated concept illustration. It is not a screenshot or a demonstration of actual results.

LICENSE

GPL-3.0-or-later. Full license and source are included in the archive.