Env fog controller

Entity Description

The env_fog_controller entity determines the density of aerial fog for the whole map.

Template:Map properties Only the first instance of the env_fog_controller entity in a level will be used. It is pointless to place multiple env_fog_controller entities in a map!.

Tip:By adding fog to a level, you can hide a far clip plane, and reduce the amount of rendered geometry, improving game performance.

Adding fog (to represent haze, mist, diffuse smoke or dust) to the atmosphere has important implications for 'realistic' Lighting. Light is scattered and absorbed as it passes through fog. The denser the fog, the greater the effect.

• Falloff - (or attenuation) is the rate at which light intensity decreases over distance. Falloff distance decreases as fog gets thicker.
• Tyndall Effects - can be seen when the fog particles reflect light toward the viewer. Halos and Lightbeams become more visible as fog gets thicker.
• Diffused Lighting - the boundary-line between light and shadow becomes more blurred (diffuse) as fog gets thicker. See Lightmap Scale and shadow_control's "distance" parameter.

See Also

• Fog tutorial
• Dust, Fog, & Smoke

Keyvalues

• Template:Kv targetname
• Template:Kv angles
• Template:Kv dxlevelchoice
• fogcolor

⇆#000000rgb(0,0,0)⇆

• fogcolor2

⇆#000000rgb(0,0,0)⇆

• fogdir

<vector> A vector (given by three space-separated numbers X Y Z) which points from the secondary fog color fogcolor2 towards the primary fog color fogcolor.

• fogstart

<float> How far from the point-of-view the fog should start.

• fogend

<float> How far from the point-of-view the view should be completely fogged.

• farz

<integer> This is the distance from the point-of-view that the level geometry should stop being drawn at. This can be used to control engine performance.

• fogenable

<boolean>

• fogblend

<boolean> This will enable blending between two fog colors, based on the direction the player is looking. If the player's viewpoint is equal to the fogdir vector, the fog will be drawn with the secondary color; if facing in the complete opposite direction, the fog will be drawn with the primary color.

This can be used to approximate the aesthetic effect of diffuse light filtering through the fog, but since the fog effect color is changed for the entire rendered scene, it is best to keep the two colors relatively close to make the blending less obvious.

For example, sunlight with a yaw of 45 degrees and a pitch of -45 degrees could be enhanced using a fogdir of '-1 -1 1', a fogcolor of '120 110 100' and a fogcolor2 of '80 70 60'.

• use_angles

<boolean>

• Template:Ep1 add

<float> Interpolate time

Inputs

• Template:I targetname
• SetStartDist <float>

Set the fog start distance.

• SetEndDist <float>

Set the fog end distance.

• TurnOn

Turn the fog on.

• TurnOff

Turn the fog off.

• SetColor ⇆#000000rgb(0,0,0)⇆

Set the primary fog color.

• SetColorSecondary ⇆#000000rgb(0,0,0)⇆

Set the secondary fog color.

• SetFarZ <integer>

Set the far clip plane distance.

• SetAngles <angles>

Set the angles to use for the secondary fog direction.

• Template:Ep1 add

Set the primary fog color.

• Template:Ep1 add

Set the secondary fog color.

• Template:Ep1 add

Set the fog start distance.

• Template:Ep1 add

Set the fog end distance.

• Template:Ep1 add

Start fog transition.

Outputs

• Template:O targetname