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# GaussianSplatResource.ActivationFunction

A transformation the framework applies to raw scale or opacity values
before rendering.

```
enum ActivationFunction
```

## Overview

Trained Gaussian splat models often store scale and opacity in a form
that needs a mathematical transformation. Choose the function that
matches how your data was trained.

## Topics

### Enumeration Cases

[`case exponential`](/documentation/RealityKit/GaussianSplatResource/ActivationFunction/exponential)

Applies an exponential function to each value.

[`case identity`](/documentation/RealityKit/GaussianSplatResource/ActivationFunction/identity)

Uses the values without transformation.

[`case sigmoid`](/documentation/RealityKit/GaussianSplatResource/ActivationFunction/sigmoid)

Applies a sigmoid function to each value.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

---

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