Wearables

A wearable is a GLB skinned to the official Decentraland avatar armature (or a 256 px PNG for eyes, eyebrows and mouth), uploaded to a collection in the Builder. This skill covers making that file. For driving Blender (headless CLI vs Blender MCP, binary paths, the never-fall-back-silently rule, PBR-only, no lights/cameras) see {baseDir}/../add-3d-models/references/blender-authoring.md; this skill only adds what is specific to wearables.

RULE: Start from the official base meshes

Never build an avatar mesh or armature by hand. The Decentraland Tools add-on ships them in assets/:

The A = female / B = male mapping is not obvious from the names. Get it right or the representations end up swapped. The mapping was confirmed by rendering both files and measuring their meshes: ShapeA_* has narrower shoulders (0.66 vs 0.80 m), a pinched waist and wider hips (0.41 vs 0.37 m). If in doubt, render the two bodies from the front before building.

The base meshes are already weighted to the 62 avatar bones. The fastest route to a body-hugging wearable is to start from the base mesh of its category (the upper-body mesh has uBody in its object name). Reshape it or inflate it slightly along its normals, delete every other mesh, and add rigid parts.

RULE: One representation per body shape

Body-hugging wearables need a GLB per body shape: build from AvatarShape_B.blend for BaseMale and AvatarShape_A.blend for BaseFemale. Script the build and run it once per file (-- male / -- female). A rigid accessory that fits both (glasses, a hat) can be one GLB listed for both body shapes. In the Builder, upload one representation, then add the other from the item editor (… → Add male/female representation). For a smart wearable, both go in wearable.json (see smart-wearables).

Categories and limits

• Hiding another slot adds its budget. An upper_body that hides lower_body (a jumpsuit) may use 3,000. A helmet that hides every head category may use 4,000.
• ≤ 2 materials (not counting AvatarSkin_MAT) and ≤ 2 textures, square, ≤ 1024 px.
• No normal or roughness maps; the avatar uses a toon shader. Bake detail and AO into the base color. Emission goes in its own material; prefer alpha clip over alpha blend.
• hands_wear accepts hand accessories, items that replace the hands, and items held in the hand (tools, props). All must be skinned to the avatar armature.
• Source: Creating wearables.

Special materials and categories

• Hair / facial hair tinted by the player's hair color: paint in grayscale and include Hair in the material name (e.g. M_Hair_Short). Leave Hair out of materials that shouldn't tint.
• Skin is tinted only if the material is named exactly AvatarSkin_MAT (grayscale texture). A wearable that shows skin (bare arms) keeps that material on those faces.
• Eyes / eyebrows / mouth: 256 px transparent PNG. A grayscale mask PNG with the _mask suffix limits where the tint applies. Upload both files in one zip.
• Hats: add a short hair to the hat mesh and hide the hair category so long hair doesn't clip through.
• Dangling parts (ponytails, earrings, capes) can sway with extra bones named *springbone*: see Spring bones.

Armature and skinning rules

• Export Armature exactly as shipped: same names, hierarchy and transforms. No _end / _neutral leaf bones (toggle Ignore Leaf Bones when importing FBX). Spring bones are the only extra bones allowed.
• A valid single-mesh wearable GLB has 64 nodes: Armature + 62 bones + 1 skinned mesh.
• Seams with other body parts: weight the neck-line vertices 100% to the neck bone and the waist-line vertices 100% to the hips, so separate wearables meet without gaps. Use the leg bones for the lower body / feet seam.
• Rigid parts (a backpack, tanks, armor plates): weight every vertex 100% to one bone (e.g. Avatar_Spine2 for anything on the back). Give the object the same armature parent and an Armature modifier, then join it into the body mesh so the wearable stays one skinned mesh.
• A rigid part on the back floats unless you measure the gap. A jetpack placed at a constant offset (the furthest-back point of the whole upper back + 12 mm) stood 2–10 cm off the back under its own footprint, and it read as floating from the side. The back curves away from a flat-fronted part. Two fixes, verified in Blender renders but not yet re-checked in-world:
  • Ray-cast the body (or the inflated suit) along the back-to-front axis over the part's own footprint. Set the part's front face from the furthest-back hit, leaving ~4 mm.
  • Add a small mount block between part and back (9 × 16 cm on the jetpack; the owner rejected a full-width plate as too heavy). Ray-cast its front vertices onto the surface and give each the skin weights of the nearest body vertex (mathutils.kdtree.KDTree). Weight its back vertices, which sit inside the part, 100% to the part's bone. The mount bends with the spine where the rigid part cannot.
• ≤ 4 bone influences per vertex; keep left/right weighting symmetric.

Blender gotchas (hit in practice)

• bpy.ops.object.join() drops material indices of an object that had no material slots: the joined faces all end up on material 0 (a rigid part came out textured with the suit texture). Store a per-face int attribute (bm.faces.layers.int.new('part')) before joining. After assigning materials, restore material_index from it, then remove the attribute before export.
• After joining, wipe the old UV maps and create one new UVMap. Unwrap each material's faces separately (select by material_index, then uv.smart_project(scale_to_bounds=True)) so each fills its own texture.
• Blender resolves a relative render output path against the .blend file's folder, not the working directory. Pass absolute paths for thumbnails and renders.

Textures that read well on the avatar

Procedural textures painted per texel with hard edges look like pixel art (stair-stepped stripes). The owner rejected that as "too 8-bit". For a "real object" look:

• Paint at 1024 px with supersampling (render at 2× and average), or draw stripes and panels with a soft 1–2 texel edge.
• Add seams and stitching along panel borders, light wear, and a baked AO pass (Cycles bake) multiplied in.
• Fill UV gutters (dilate island colors outward ~40 px) so mip-mapping doesn't bleed dark edges into the islands.

Export

Select only Armature and the wearable mesh, then:

bpy.ops.export_scene.gltf(
    filepath=path, export_format='GLB', use_selection=True,
    export_skins=True, export_animations=False, export_morph=False,
    export_materials='EXPORT',
    export_image_format='JPEG', export_jpeg_quality=88,   # PNG at 1024 px is several times larger
    export_cameras=False, export_lights=False, export_yup=True, export_apply=False,
)

JPEG keeps a 1,230-tri upper-body suit with two 1024 px textures at ~270–280 KB per body shape. Use PNG only for a texture that needs alpha. The Builder's limit is 3 MB per item.

Verify each GLB before uploading: parse the JSON chunk and check the node count (64 for a single-mesh wearable), the triangle count against the table above, ≤ 2 materials and ≤ 2 images at ≤ 1024 px. The Builder shows the same triangle, material and texture counts under Properties after upload.

Thumbnail

256 × 256 PNG with a transparent background, showing the wearable only: no avatar body and no extra graphics (the Curation Committee rejects those). Render with film_transparent = True at a 3/4 view and hide the body meshes. Keep the editable .blend and build script in a blender/ folder.

Upload (regular wearables)

1. Builder → Collections → create or open a collection → New item → drop the GLB (or a zip with GLB + textures). The Builder detects wearable vs emote.
2. Choose the body shape, name, rarity (unique 1 · mythic 10 · exotic 50 · legendary 100 · epic 1,000 · rare 5,000 · uncommon 10,000 · common 100,000) and category; add the thumbnail.
3. In the item editor: add the other body-shape representation, set overrides (categories and base body parts it hides), description and tags. Overrides are defaults; players can change them in the backpack.
4. Preview it on avatars of both body shapes and play a few emotes to catch skinning problems. Then use See in Decentraland on the collection to try it in-world on Sepolia.
5. Publishing goes through the Curation Committee.

Docs: Uploading wearables.