image-to-relief-stl

# image-to-relief-stl

Generate a **watertight, printable STL** from an input image by mapping colors (or grayscale) to heights.

This is an orchestrator-friendly workflow:
- Use **nano-banana-pro** (or any image model) to generate a **flat-color** image.
- Run this skill to convert it into a **bas-relief** model.

## Practical constraints (to make it work well)

Ask the image model for:
- **exactly N solid colors** (no gradients)
- **no shadows / no antialiasing**
- bold shapes with clear edges

That makes segmentation reliable.

## Quick start (given an image)

```bash
bash scripts/image_to_relief.sh input.png --out out.stl \
  --mode palette \
  --palette '#000000=3.0,#ffffff=0.0' \
  --base 1.5 \
  --pixel 0.4
```

### Grayscale mode

```bash
bash scripts/image_to_relief.sh input.png --out out.stl \
  --mode grayscale \
  --min-height 0.0 \
  --max-height 3.0 \
  --base 1.5 \
  --pixel 0.4
```

## Outputs

- `out.stl` (ASCII STL)
- optional `out-preview.svg` (vector preview via potrace; best-effort)

## Notes

- This v0 uses a **raster heightfield** meshing approach (robust, no heavy CAD deps).
- The `--pixel` parameter controls resolution (smaller = higher detail, bigger STL).