Agent Skills › EL4CTEO/blender-skills › blender-facial-shapekeys

blender-facial-shapekeys

GitHub

提供Blender面部绑定与Shape Keys工作流，涵盖ARKit混合形状、口型同步及对称处理。指导从网格准备、雕刻、镜像到驱动器和引擎导出的全流程，确保兼容Unity/Unreal等游戏引擎的标准规范。

skills/blender-facial-shapekeys/SKILL.md EL4CTEO/blender-skills

触发场景

需要创建或修复Blender角色面部绑定制作符合ARKit标准的表情混合形状为游戏或VR应用导出面部动画资源解决面部Shape Keys的拓扑或命名问题

安装

npx skills add EL4CTEO/blender-skills --skill blender-facial-shapekeys -g -y

更多选项

不安装直接使用

npx skills use EL4CTEO/blender-skills@blender-facial-shapekeys

指定 Agent (Claude Code)

npx skills add EL4CTEO/blender-skills --skill blender-facial-shapekeys -a claude-code -g -y

安装 repo 全部 skill

npx skills add EL4CTEO/blender-skills --all -g -y

预览 repo 内 skill

npx skills add EL4CTEO/blender-skills --list

SKILL.md

Frontmatter

{
    "name": "blender-facial-shapekeys",
    "license": "MIT",
    "metadata": {
        "author": "blender-agent-skills",
        "version": "1.2.0"
    },
    "description": "Facial rigs and shape keys in Blender 5.3 - ARKit 52 blendshapes, visemes for lip-sync, sculpting expressions, splitting symmetric shapes into Left\/Right, mirroring, corrective and combination shapes, drivers and control rigs, bone+blendshape hybrids, export to engines (Unity, Unreal, Roblox dynamic heads, VRM\/web). Use for faces, expressions, lip-sync, or any shape-key work."
}

Facial Rig & Shape Keys

The execution model is in blender-core. The body rig is in blender-character-rigging.

Choose the approach

Approach	Use	Notes
Blendshapes (ARKit 52)	games, VTubers, mocap (iPhone/Live Link Face), web/VRM	the industry interchange set; each shape is sculpted
Bones (jaw, eyes, lids, brows, lips)	stylized, low memory, mobile	jaw + eyes as bones are almost always right
Hybrid	most production game heads	jaw/eye/tongue bones + blendshapes for everything soft
Rigify face (`human` metarig)	film-style keyframe animation inside Blender	100+ face bones, heavy for engines

Procedure (blendshapes)

The head mesh needs clean loops around the eyes and mouth (blender-retopology-uv), with eyes, teeth and tongue as separate objects parented or weighted to bones.
scripts/shapekeys.py -- --mesh Head --create arkit (or --create visemes for the 15 Oculus visemes) creates empty, correctly named keys.
Sculpt each key (live: sculpt mode on the active key, use_shape_key_edit_mode). Symmetric expressions can be sculpted once, then --split eyeBlink gives eyeBlinkLeft/Right with a soft blend across X=0 (--falloff m).
--mirror browDownLeft builds browDownRight (topology-independent mirror).
--report lists unsculpted keys, the max offset per key, and missing ARKit names. A shape is done only when every key moves and nothing is left over.
Optional: --drivers FaceCtrl adds a controller with 0–1 custom properties driving each key, for keyframing in Blender.
Check the extremes and combinations (jawOpen + mouthSmile, eyeBlink + eyeSquint) with look. Fix them with corrective combination keys driven by the product of two keys.

Shape key rules

Shapes are deltas from Basis. Never change the Basis topology after creating keys (adding or removing verts destroys every key).
One action per key. No head or neck movement inside face keys (bones do that). Keep eyelids sliding over the eye surface, not through it (check with blender-asset-qa zfighting on lid/eye).
Range 0–1. slider_max can be raised for exaggeration, but engines clamp to 0–1.
Relative keys (use_relative=True, the default) are the only kind that exports.
Name exactly per spec (case-sensitive): eyeBlinkLeft, not EyeBlink_L. Engines map by name.
Keys on meshes with Subdivision: sculpt at level 0, and keep the subdivision modifier after the shape keys (they're evaluated first anyway).
Applying modifiers on a mesh with shape keys fails. Use modifier_apply_as_shapekey for deform modifiers, or apply them before creating keys.

Correctives and combination shapes

Corrective for a bone pose: sculpt in the posed state, then drive with a TRANSFORMS variable (ROT_X, LOCAL_SPACE, mapped to 0–1).
Combination: key jawOpen_mouthSmile with driver SCRIPTED expression a*b, from the two key values (SINGLE_PROP key_blocks["jawOpen"].value). Simple expressions don't need Python auto-run.

Engine notes

Unity: FBX blendshapes. In the Model importer, set Blend Shape Normals = Calculate (or Import if smoothing was exported). ARKit names map to the AR Foundation face-tracking samples.
Unreal: morph targets ("Import Morph Targets"). Live Link Face / MetaHuman Animator use ARKit names, and the Pose Asset maps the curves. No leaf bones.
Roblox dynamic heads: FACS-based poses with Roblox-specific names, authored as animation frames on a head rig (Creator Hub "Dynamic heads" spec). Build from the official Blender template. ARKit sculpts can be reused by renaming/mapping. Head ≤ 4,000 tris.
VRM / web (three-vrm, ReadyPlayerMe-style): ARKit 52 + visemes as glTF morph targets (export_morph=True). Keep the morph-normal export on only if shading needs it (it doubles the size).
Drop unused keys before export. Every key costs memory per vertex (glTF sparse accessors help).

Gotchas

ob.shape_key_add(from_mix=False) copies the Basis. from_mix=True bakes the current mix (useful for combos, dangerous by accident).
shape_key_mirror(use_topology=False) needs a mesh symmetric on X. Run it on the active key (the script handles this).
Driver variables on shape keys use the Key ID (ob.data.shape_keys), not the mesh: fc = kb.driver_add("value").