This article's documentation is for anything that uses the Source engine. Click here for more information.


From Valve Developer Community
Jump to: navigation, search

light is a point entity available in all Source Source games.

English (en)Русский (ru)
class hierarchy
CLight defined in lights.cpp

It creates an invisible static light source that shines in all directions.



Name (targetname) <string>
The targetname that other entities refer to this entity by.
Icon-Important.pngImportant:Naming a static light radically changes its behavior. See Naming Lights for details.
Entity To Point At (target) <targetname> Obsolete
Deprecated. Entity to point this light at. Non-functional, as this entity casts light in all directions, all the time.
Maximum Distance (_distance) <integer>
This is the distance that light is allowed to cast, in inches. Non-functional in Source 2013 Source 2013 and later, use 50 and 0 percent falloff instead.

Brightness (_light) <color255 + int>
The RGB color and brightness of the light. Colors must be between 0 and 255; brightness can be anything.
Note.pngNote:Negative brightness will suck out the amount of lighting that the equivalent positive brightness will cast. Use sparingly; set falloff to linear instead of quadratic to make it more like an ordinary shadow and less like a black hole.
BrightnessHDR (_lightHDR) <color255 + int>
Brightness override used in HDR mode. Default is -1 -1 -1 1, which means no change.
Warning.pngWarning:The fourth digit must be positive. Otherwise all light will be sucked out of your map!
BrightnessScaleHDR (_lightHDRscale) <float>
A simple intensity multiplier used when compiling HDR lighting.
Appearance (style) <choices>
Various Custom Appearance presets.
Warning.pngWarning:Using this parameter near displacements reduces performance!
Light Appearances
Literal Value Description Sequence Preview
0 Normal m Sequence 0.gif
10 Fluorescent flicker mmamammmmammamamaaamammma Sequence 10.gif
2 Slow, strong pulse abcdefghijklmnopqrstuvwxyzyxwvutsrqponmlkjihgfedcba Sequence 2.gif
11 Slow pulse, noblack abcdefghijklmnopqrrqponmlkjihgfedcba Sequence 11.gif
5 Gentle pulse jklmnopqrstuvwxyzyxwvutsrqponmlkj Sequence 5.gif
1 Flicker A mmnmmommommnonmmonqnmmo Sequence 1.gif
6 Flicker B nmonqnmomnmomomno Sequence 6.gif
3 Candle A mmmmmaaaaammmmmaaaaaabcdefgabcdefg Sequence 3.gif
7 Candle B mmmaaaabcdefgmmmmaaaammmaamm Sequence 7.gif
8 Candle C mmmaaammmaaammmabcdefaaaammmmabcdefmmmaaaa Sequence 8.gif
4 Fast strobe mamamamamama Sequence 4.gif
9 Slow strobe aaaaaaaazzzzzzzz Sequence 9.gif
12 !FGD Underwater light mutation mmnnmmnnnmmnn Sequence 12.gif
Custom Appearance (pattern) <string>
A string of characters, like a sequence of piano keys, that define a pattern of brightness. a is dark and z is full intensity. Applies only to lights with a targetname.
Constant (_constant_attn) <float>
Linear (_linear_attn) <float>
Quadratic (_quadratic_attn) <float>
These three values determine how the intensity of the emitted light falls off over distance. See Constant-Linear-Quadratic Falloff.
50 percent falloff distance (_fifty_percent_distance)) <string>
0 percent falloff distance (_zero_percent_distance) <string>
Distances at which brightness should have fallen to 50% and (1/256)% respectively. Overrides Linear/Constant/Quadratic parameters if non-zero.
Icon-Bug.pngBug:Using this setting will sometimes not work, which may or may not be related to using the light inside of an instance. Collapsing the instance and messing with the light's falloff values seems to help.
Hard falloff (_hardfalloff) <boolean>
Causes lights to fall to exactly zero beyond the 0% distance. May cause unrealistic lighting if not used carefully.
Cast entity shadows (_castentityshadow) <boolean> (in all games since Left 4 Dead) (also in Garry's Mod)
Allows the light to modify the direction of nearby render-to-texture shadows so that they always point away from its origin. See also shadow_control.
Note.pngNote:This keyvalue may not be available in some FGDs.
Shadow cast offset (_shadoworiginoffset) <vector> (in all games since Left 4 Dead)
A world-space offset that gets applied to the light origin when casting entity shadows. Useful for dealing with funny-looking shadows from very low lights: Just offset up the z axis. Default 0 0 0.
Note.pngNote:This keyvalue may not be available in some FGDs.
Confirm:How many of the BaseEntity keyvalues even work on static lights? Does parenting work?


  •  [1] : Initially dark
       Spawns with the light turned off, so a light switch or similar can turn it on.


Turn the light on.
The the light off.
Toggle the light's current state.
SetPattern <string>
Set a custom pattern of light brightness for this light. If the Light is off, then this input appears to turn it on.
FadeToPattern <string>
Fades from first value in old pattern, to first value in the new given pattern. If the Light is off, then this input appears to turn it on.

See also