---
title: "SkySpecification | JavaScript maps SDK"
description: "Documentation for MapTiler SDK"
---

> For AI agents: a documentation index is available at [/llms.txt](https://docs.maptiler.com/llms.txt). Markdown versions of all pages are available by appending .md to any URL.

# Type Alias SkySpecification

type SkySpecification \= {  
    ["atmosphere-blend"](#atmosphere-blend)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>;  
    ["atmosphere-blend-transition"](#atmosphere-blend-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["fog-color"](#fog-color)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>;  
    ["fog-color-transition"](#fog-color-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["fog-ground-blend"](#fog-ground-blend)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>;  
    ["fog-ground-blend-transition"](#fog-ground-blend-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["horizon-color"](#horizon-color)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>;  
    ["horizon-color-transition"](#horizon-color-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["horizon-fog-blend"](#horizon-fog-blend)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>;  
    ["horizon-fog-blend-transition"](#horizon-fog-blend-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["sky-color"](#sky-color)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>;  
    ["sky-color-transition"](#sky-color-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
    ["sky-horizon-blend"](#sky-horizon-blend)?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>;  
    ["sky-horizon-blend-transition"](#sky-horizon-blend-transition)?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/);  
}

##### Index

### Properties[](#properties)

[atmosphere-blend?](#atmosphere-blend) [atmosphere-blend-transition?](#atmosphere-blend-transition) [fog-color?](#fog-color) [fog-color-transition?](#fog-color-transition) [fog-ground-blend?](#fog-ground-blend) [fog-ground-blend-transition?](#fog-ground-blend-transition) [horizon-color?](#horizon-color) [horizon-color-transition?](#horizon-color-transition) [horizon-fog-blend?](#horizon-fog-blend) [horizon-fog-blend-transition?](#horizon-fog-blend-transition) [sky-color?](#sky-color) [sky-color-transition?](#sky-color-transition) [sky-horizon-blend?](#sky-horizon-blend) [sky-horizon-blend-transition?](#sky-horizon-blend-transition)

## Properties[](#properties-1)

### `Optional`atmosphere-blend[](#atmosphere-blend)

"atmosphere-blend"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>

How to blend the atmosphere. Where 1 is visible atmosphere and 0 is hidden. It is best to interpolate this expression when using globe projection.

#### Default[](#default)

```typescript
0.8
```

### `Optional`atmosphere-blend-transition[](#atmosphere-blend-transition)

"atmosphere-blend-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`fog-color[](#fog-color)

"fog-color"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>

The base color for the fog. Requires 3D terrain.

#### Default[](#default-1)

```typescript
"#ffffff"
```

### `Optional`fog-color-transition[](#fog-color-transition)

"fog-color-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`fog-ground-blend[](#fog-ground-blend)

"fog-ground-blend"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>

How to blend the fog over the 3D terrain. Where 0 is the map center and 1 is the horizon.

#### Default[](#default-2)

```typescript
0.5
```

### `Optional`fog-ground-blend-transition[](#fog-ground-blend-transition)

"fog-ground-blend-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`horizon-color[](#horizon-color)

"horizon-color"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>

The base color at the horizon.

#### Default[](#default-3)

```typescript
"#ffffff"
```

### `Optional`horizon-color-transition[](#horizon-color-transition)

"horizon-color-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`horizon-fog-blend[](#horizon-fog-blend)

"horizon-fog-blend"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>

How to blend the fog color and the horizon color. Where 0 is using the horizon color only and 1 is using the fog color only.

#### Default[](#default-4)

```typescript
0.8
```

### `Optional`horizon-fog-blend-transition[](#horizon-fog-blend-transition)

"horizon-fog-blend-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`sky-color[](#sky-color)

"sky-color"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<[ColorSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/ColorSpecification/)\>

The base color for the sky.

#### Default[](#default-5)

```typescript
"#88C6FC"
```

### `Optional`sky-color-transition[](#sky-color-transition)

"sky-color-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)

### `Optional`sky-horizon-blend[](#sky-horizon-blend)

"sky-horizon-blend"?: [PropertyValueSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/PropertyValueSpecification/)<number\>

How to blend the sky color and the horizon color. Where 1 is blending the color at the middle of the sky and 0 is not blending at all and using the sky color only.

#### Default[](#default-6)

```typescript
0.8
```

### `Optional`sky-horizon-blend-transition[](#sky-horizon-blend-transition)

"sky-horizon-blend-transition"?: [TransitionSpecification](https://docs.maptiler.com/sdk-js/api-reference/types/TransitionSpecification/)