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# GLKEffectPropertyFog

Fog drawing information for use in GLKit rendering effects.

```
class GLKEffectPropertyFog
```

## Overview

These properties are specifically designed to mimic the fog calculations provided by OpenGL ES 1.1.

When fog is enabled, the fog component is calculated and clamped to a range from `0.0` to `1.0`. Then, the fog value is used as a blending factor between the computed fragment color and the fog color.

## Topics

### Enabling Fog

[`enabled`](/documentation/GLKit/GLKEffectPropertyFog/enabled)

A Boolean value that indicates whether fog is applied to the fragment color.

### Choosing the Fog Mode

[`mode`](/documentation/GLKit/GLKEffectPropertyFog/mode)

The algorithm used to compute the density of the fog applied to the fragment color.

### Fog Properties

[`color`](/documentation/GLKit/GLKEffectPropertyFog/color)

The color of the fog at maximum density.

[`density`](/documentation/GLKit/GLKEffectPropertyFog/density)

The rate at which the fog exponent increases.

[`start`](/documentation/GLKit/GLKEffectPropertyFog/start)

The minimum distance in eye coordinates before fog is applied to the fragment color.

[`end`](/documentation/GLKit/GLKEffectPropertyFog/end)

The distance in eye coordinates where fog completely covers the color fragment.

### Constants

[`GLKFogMode`](/documentation/GLKit/GLKFogMode)

A mode that describes how the fog component is calculated for the fragment.

## Relationships

### Conforms To

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

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

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

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

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

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

### Inherits From

[`GLKEffectProperty`](/documentation/GLKit/GLKEffectProperty)

---

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