render-glb

# Render GLB to Image

Render 3D GLB files to PNG images so agents can **visually verify their work**.

## Zero-Setup with bunx

```bash
bunx render-glb model.glb output.png
```

No installation required. First run downloads the tool, subsequent runs are instant.

## Why This Matters

Agents can generate 3D models but typically can't see them. This creates a **visual verification loop**:

1. Generate model → export GLB
2. Render GLB → PNG
3. Read PNG → see what you built
4. Iterate if needed

## Basic Usage

```bash
# Render with defaults (good for most cases)
bunx render-glb model.glb preview.png

# Then read the image to see your work
# (use Read tool on preview.png)
```

## Options

```bash
bunx render-glb <input.glb> <output.png> [options]

Options:
  --width <n>      Image width in pixels (default: 800)
  --height <n>     Image height in pixels (default: 600)
  --background <hex>  Background color (default: #808080)
```

## Visual Verification Workflow

When building 3D models, use this pattern:

```python
# 1. Build your model
from build123d import Box, Sphere, export_gltf
model = Box(20, 20, 20) + Sphere(radius=15)
export_gltf(model, "./model.glb", binary=True)
```

```bash
# 2. Render to image
bunx render-glb model.glb preview.png
```

```
# 3. Read the image (using Read tool)
# Now you can SEE what you built and verify it's correct
```

## Integration with CAD Skills

This skill complements:
- **build123d** - Python CAD modeling
- Any tool that exports GLB format

Typical workflow:
1. Use CAD skill to generate geometry
2. Export to GLB
3. Use render-glb to verify visually
4. Iterate if model isn't correct

## Links

- npm: https://www.npmjs.com/package/render-glb
- GitHub: https://github.com/rawwerks/render-glb