# Snapshot blend · zvuk

zvuk v1.14.1 · MIT · https://zvuk.schmooky.dev/examples/snapshot-blend/

Two captured snapshots, one Parameter, interpolated mix per frame. The full vanilla source is on GitHub.

Example

# Snapshot blend

Two captured snapshots, one Parameter, interpolated mix per frame. The full vanilla source is on GitHub.

Click **Unlock & start** to load two music layers and begin looping them. Now drag the slider. Every change calls `engine.blendSnapshots(calm, combat, t)`, which snaps the live mix to `lerp(calm, combat, t)`. The music bus fades in and the drums bus comes up, both from the one knob.

music busidle

tensiont = 0.00

stream (t=0)mid (t=0.5)fire (t=1)

music bus: 0.60

drums bus: 0.00

Unlock & start

## How it's wired

snapshot-blend (excerpt) ts

```
// Capture two mix shapes — calm and combat.
engine.bus('music').level = 0.6;
engine.bus('drums').level = 0.0;
const calm = engine.captureSnapshot('calm');

engine.bus('music').level = 0.25;
engine.bus('drums').level = 0.85;
const combat = engine.captureSnapshot('combat');

// Drive blendSnapshots from a Parameter; the slider feeds 'tension'.
const tension = engine.parameter('tension', 0);
tension.subscribe((t) => engine.blendSnapshots(calm, combat, t));

slider.addEventListener('input', () => tension.set(Number(slider.value)));
```

The vanilla version of this demo lives at [`examples/snapshot-blend/`](https://github.com/schmooky/zvuk/tree/main/examples/snapshot-blend). It is a zero-build `index.html` and `main.ts` pair you can deploy as it stands.

## Related

-   [Snapshot](/concepts/snapshot/) covers capture, apply and blend.
-   [Parameter](/concepts/parameter/) is the named knob driving the blend.
-   [All examples](/examples/)