# Silk

Folds of silk with a bright highlight along each crest.

## Installation

```sh
pnpm add astro-dither
```

Or copy the source into your project:

```sh
npx astro-dither add effect
```

## Usage

```astro
---
import { DitherEffect } from "astro-dither";
---

<DitherEffect effect="silk" />
```

A sine sheet warped by noise. `warp` bends the folds and `sharp` decides how the crests catch the light, from soft cloth to hard moire.

The props group like this:

Fold: `warp`. Highlight: `sharp`.

## Examples

### Soft cloth

Low `sharp` flattens the crests into a gentle sheen.

```astro
<DitherEffect effect="silk" params={{"sharp":1.5,"warp":3}} />
```

### Deep folds

High `warp` pulls the sheet into tight, overlapping ridges.

```astro
<DitherEffect effect="silk" params={{"sharp":4,"warp":8}} />
```

## Props

| Prop | Type | Default | Description |
| --- | --- | --- | --- |
| `sharp` | `number` | 3 | Crest highlight sharpness. 1 to 8. |
| `warp` | `number` | 5 | Fold bending. 0 to 10. |
| `palette` | `string[]` | the effect's | 2 to 8 colours, paper first, brightest last. `transparent` works. |
| `cell` | `number` | 2 | Size of one dither cell in CSS pixels. Rounded to whole device pixels so cells stay even. |
| `matrix` | `2 | 4 | 8 | "noise"` | 8 | The Bayer threshold size, or noise for a random look. |
| `speed` | `number` | 1 | Playback speed. 0 draws one still frame. |
| `stillTime` | `number` | the effect's | The moment drawn when motion is off or reduced, in seconds. |
| `levels` | `number` | 0 (all) | Tones the field snaps to before dithering. Low values give hard, posterised steps. |
| `bloom` | `number` | 0 | Bloom around lit cells, 0 to 1. Set a positive prop to create the overlay before overriding it with CSS `--dither-bloom`. |
| `bloomRadius` | `number` | 10 | Bloom blur in CSS pixels. CSS `--dither-bloom-radius` overrides it. |
| `class` | `string` | undefined | Classes on the surface element, for size and position. |

## Notes

* Decorative and `aria-hidden`. Put real text on top, not inside it.
* With reduced motion it draws one still frame (at 4s) and stops.
* It pauses when scrolled out of view or when the tab is hidden.
* Shares one WebGL context with every other ordered effect on the page.