# Rengi Forge GLB Collision Shape Generator (V-HACD)

> Rengi Forge GLB Collision Shape Generator (V-HACD) is a paid API for AI agents from rengi.dev, paid per call via x402, $0.15/call, status unknown (last checked 2026-10-22).

Generates engine-ready convex hull collision shapes from a GLB model using V-HACD decomposition, outputting Godot, Unreal, Unity, and engine-agnostic formats.

## Facts

- Endpoint: POST https://rengi.dev/v1/glb-optimizer/colliders?utm_source=zero.xyz
- Price: $0.15/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/rengi-forge-glb-collision-shape-generator-v-hacd-d45446f1
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_1QOsKQpcRuGJC4taG97sf

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability rengi-forge-glb-collision-shape-generator-v-hacd-d45446f1 -d '<json body>'
```

Example prompt: Take my GLB file at https://assets.example.com/character.glb and generate convex hull colliders for all engines using up to 24 hulls, a resolution of 200000, and a max of 64 vertices per hull.

## When to prefer this

Choose this endpoint when you need engine-ready physics collision shapes automatically generated from a GLB model without manual authoring. It is uniquely suited for Godot, Unreal, and Unity pipelines simultaneously, outputting the correct naming conventions and node structures for each. Prefer it over manual DCC tool workflows or generic mesh-processing APIs when you need V-HACD convex decomposition with per-engine formatting in one step.

## Known failure modes

- GLB file exceeds size limit — returns error
- Invalid GLB URL or inaccessible resource — returns 400/fetch error
- maxHulls out of range (must be 1–64) — validation error
- resolution out of range (must be 10000–1000000) — validation error
- maxVerticesPerHull out of range (must be 8–255) — validation error
- Malformed GLB geometry that V-HACD cannot decompose — processing error
- Payment not provided or insufficient — 402 Payment Required

## How this service works

GLB optimizer: Collision for a model: a set of convex hulls that hug the shape (V-HACD), ready for Godot (-convcolonly nodes), Unreal (UCX_ names) and Unity (convex MeshColliders via an editor script), plus hulls.json for any engine and a see-through overlay to check. Full schema: https://rengi.dev/v1/glb-optimizer/schema

## Output

Returns a modified GLB containing engine-specific collision geometry (Godot -convcolonly nodes, Unreal UCX_ meshes, Unity convex MeshCollider-compatible meshes), a hulls.json file with hull data for any engine, and a see-through overlay GLB for visual inspection of hull coverage.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "glb": {
   "type": "string"
  },
  "engine": {
   "enum": [
    "all",
    "godot",
    "unreal",
    "unity"
   ],
   "type": "string",
   "default": "all"
  },
  "glbUrl": {
   "type": "string",
   "format": "uri"
  },
  "maxHulls": {
   "type": "integer",
   "default": 16,
   "maximum": 64,
   "minimum": 1,
   "description": "Upper limit; the fewest hulls that fit the shape (within 3% of the volume the limit gives) are used."
  },
  "resolution": {
   "type": "integer",
   "default": 100000,
   "maximum": 1000000,
   "minimum": 10000,
   "description": "Voxels used to read the shape; higher follows small details."
  },
  "maxVerticesPerHull": {
   "type": "integer",
   "default": 64,
   "maximum": 255,
   "minimum": 8,
   "description": "64 keeps every hull valid for Unity convex MeshColliders (255 polygons)."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/rengi-forge-glb-collision-shape-generator-v-hacd-d45446f1/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from rengi.dev](https://www.zero.xyz/host/rengi.dev/llms.txt)