# Caustics · Pro

Underwater light: interfering bright lines drifting over a dark pool floor, the way sun looks through a wave. A Charcoal original. WebGL, written in the file.

This is a Charcoal UI Pro component. Its source and examples are available with a Pro seat: https://charcoalui.com/pricing

## With a Pro seat

1. Add the registry to components.json:

```json
{
  "registries": {
    "@charcoal": {
      "url": "https://charcoalui.com/r/{name}.json",
      "headers": {
        "Authorization": "Bearer ${CHARCOAL_LICENSE_KEY}"
      }
    }
  }
}
```

2. Copy your licence key from https://charcoalui.com/dashboard and put it in .env.local as CHARCOAL_LICENSE_KEY, then:

```bash
npx shadcn@latest add @charcoal/caustics
```

To read Pro source through this MCP server, reconnect it with the header "Authorization: Bearer <licence key>".

## API — Caustics
| Prop | Type | Default | Notes |
| --- | --- | --- | --- |
| `speed` | `number` | `1` |  |
| `scale` | `number` | `1` |  |
| `intensity` | `number` | `1` |  |
| `color` | `string` | `"var(--ember)"` |  |
| `className` | `string` | — |  |

See it live: https://charcoalui.com/docs/components/caustics