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Cloth Sim
Garment blockout → sim → art-direct → bake. Stable pins. Engine-friendly caches/shape keys.
When to Use
- Dresses, capes, coats, flags, banners
- Character clothing that needs drape
- Baking sim to shape keys or Alembic/USD caches
- Pre-roll settling before animation export
Workflow
Garment mesh (quad-friendly) → Vertex groups (pin/collide)
→ Cloth modifier settings → Collision objects
→ Pre-roll settle → Sim pass → Art-direct fixes
→ Bake shape keys / cache → Cleanup → ExportMesh Prep
- Quads preferred; even density on deforming areas
- Avoid long skinny triangles on folds
- Apply scale before sim
- Separate garment from body collider
Vertex Groups
| Group | Purpose |
|---|---|
PIN_Cloth | Anchors (waist, shoulders, collar) |
COL_Ignore | Optional non-colliding regions |
STIFF_High | Belts, seams that should resist stretch |
Settings Starters
| Look | Quality | Speed | Bending |
|---|---|---|---|
| Soft dress | 8–12 | 1.0 | Low |
| Stiff coat | 5–8 | 1.0 | Higher |
| Flag/cape | 8–10 | 1.0–1.5 | Low–mid |
Tune mass and air viscosity for scale. Always run a settle pre-roll.
Bake Targets
| Target | Use |
|---|---|
| Shape keys | Game poses / few frames |
| Alembic/USD | Cinematic caches |
| Armature weights | If converting to deform-only |
Constraints
MUST DO
- Apply scale; define pin groups before long sims
- Collide against simplified body capsule/mesh
- Art-direct after sim (sculpt/corrective keys)
MUST NOT DO
- Sim hero cloth on ultra-dense sculpt meshes
- Skip pre-roll (starts mid-air / exploding)
- Export raw unstable caches
Reference Guide
| Topic | Reference | Load When |
|---|---|---|
| Cloth Settings Presets | references/cloth-settings-presets.md | When needed |
| Pin And Collide | references/pin-and-collide.md | When needed |
| Bake Targets | references/bake-targets.md | When needed |
