# Fog

#### new Cesium.Fog()
Scene/Fog.js 21

  Blends the atmosphere to geometry far from the camera for horizon views. Allows for additional performance improvements by rendering less geometry and dispatching less terrain requests.

### Members

#### density : Number
Scene/Fog.js 38

  A scalar that determines the density of the fog. Terrain that is in full fog are culled. The density of the fog increases as this number approaches 1.0 and becomes less dense as it approaches zero. The more dense the fog is, the more aggressively the terrain is culled. For example, if the camera is a height of 1000.0m above the ellipsoid, increasing the value to 3.0e-3 will cause many tiles close to the viewer be culled. Decreasing the value will push the fog further from the viewer, but decrease performance as more of the terrain is rendered.
  Default Value: `2.0e-4`

#### enabled : Boolean
Scene/Fog.js 27

  `true` if fog is enabled, `false` otherwise.
  Default Value: `true`

#### screenSpaceErrorFactor : Number
Scene/Fog.js 47

  A factor used to increase the screen space error of terrain tiles when they are partially in fog. The effect is to reduce the number of terrain tiles requested for rendering. If set to zero, the feature will be disabled. If the value is increased for mountainous regions, less tiles will need to be requested, but the terrain meshes near the horizon may be a noticeably lower resolution. If the value is increased in a relatively flat area, there will be little noticeable change on the horizon.
  Default Value: `2.0`