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# threshold

The brightness threshold for bloom activation.

```
var threshold: Float
```

## Discussion

Only pixels with luminance values above this threshold will contribute
to the bloom effect. The value is typically in the range `[0.0, 1.x]`:

- `0.0` makes all pixels contribute to bloom
- `1.0` standard threshold for HDR content (default)
- `>1` only very bright highlights will bloom

Higher thresholds create more selective bloom that only affects the
brightest elements in the scene.

---

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