# rotation

> Override the rotation of particles this system emits.

## Definition

* **Type:** Property
* **Namespace:** [UnityEngine](/engine/6000.0/script-reference/unityengine.md)
* **Assembly:** UnityEngine.ParticleSystemModule

```csharp
public float rotation { get; set; }
```

### Remarks

Note that the value is an Euler angle. Additional Resources: [ParticleSystem.Particle.rotation](/engine/6000.0/script-reference/unityengine/particlesystem/particle/rotation.md).

### Examples

```csharp
using UnityEngine;

// In this example we have a Particle System emitting aligned particles; we then emit and override the rotation every 2 seconds.
public class ExampleClass : MonoBehaviour
{
    private ParticleSystem system;

    void Start()
    {
        // A simple particle material with no texture.
        Material particleMaterial = new Material(Shader.Find("Particles/Standard Unlit"));

        // Create a Particle System.
        var go = new GameObject("Particle System");
        go.transform.Rotate(-90, 0, 0); // Rotate so the system emits upwards.
        system = go.AddComponent<ParticleSystem>();
        go.GetComponent<ParticleSystemRenderer>().material = particleMaterial;

        // Every 2 seconds we will emit.
        InvokeRepeating("DoEmit", 2.0f, 2.0f);
    }

    void DoEmit()
    {
        // Any parameters we assign in emitParams will override the current system's when we call Emit.
        // Here we will override the rotation. All other parameters will use the behavior defined in the Inspector.
        var emitParams = new ParticleSystem.EmitParams();
        emitParams.rotation = 45.0f;
        system.Emit(emitParams, 10);
    }
}
```