> For the complete documentation index, see [llms.txt](https://flora.magneticarcade.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://flora.magneticarcade.com/samples/runtime-samples.md).

# Runtime Samples

## Fish Boids

The Fish Boids scene demonstrates runtime-driven instance animation at high counts using Flora + jobs.

<figure><img src="/files/aivaH4mTPFHQFme0I4pa" alt=""><figcaption></figcaption></figure>

### Scene Path

`Samples~/Examples/Fish/Scenes/FishBoidsSample.unity`

### What This Demonstrates

* Runtime creation and ownership of many instances
* Job-based transform simulation
* Batch update upload into Flora runtime

### APIs Exercised

* `FloraSystem.GetOrCreate()`
* `CreateInstances(...)`
* `ScheduleUpdateInstanceWorldTransforms(...)`
* `DestroyInstances(...)`

### Run and Verify

1. Open `FishBoidsSample` and press Play.
2. Confirm fish schools animate continuously.
3. Watch frame stability while instance counts are high.

**Expected result:** fish move smoothly as Flora instances without per-fish scene GameObjects for rendering.

### Common Failure Checks

* No fish visible: ensure Flora is active and sample objects enabled.
* Errors on disable: verify job dependencies complete before destroy/dispose.
* Motion vector artifacts: check runtime/scene motion-vector settings.

### Core Classes

#### FishSchool

```csharp
NativeArray<FloraInstanceTransform> m_Transforms;
NativeArray<FloraInstanceHandle> m_InstanceHandles;
JobHandle m_Dependency;

void OnEnable()
{
    m_Transforms = new NativeArray<FloraInstanceTransform>(SpawnCount, Allocator.Persistent);
    m_InstanceHandles = new NativeArray<FloraInstanceHandle>(SpawnCount, Allocator.Persistent);

    FloraSystem.GetOrCreate().CreateInstances(Prefab, gameObject, m_InstanceHandles, m_Transforms);
}

void OnDisable()
{
    m_Dependency.Complete();
    FloraSystem.Instance?.DestroyInstances(m_InstanceHandles);

    m_Transforms.Dispose();
    m_InstanceHandles.Dispose();
}
```