Light environment

Entity Description

The light_environment entity is a light controller, that casts both diffuse and parallel directional lighting from the toolsskybox texture. This is to approximate the light cast from the Sun or Moon.

• Template:Map properties A 3D Skybox does not require an extra light_environment placement. If multiple light_environment entities are placed, Vrad uses the keyvalues from the first placed light_environment to calculate the lighting.

Skyboxes are the main source of light for most maps, and as such are one of the most important parts of making a map.

Overview

Skybox lighting enters the map through every toolsskybox-textured brush, representing direct sun/moonlight and diffuse skylight. Its basic properties are controlled by three entities used in combination (four in some games):

• light_environment defines the direction, color and intensity of the direct sunlight, and the color and intensity of the diffuse skylight.
• shadow_control defines the color, direction, and attenuation distance of the dynamic shadows that are created by light_environment. Dynamic shadows will be buggy and unconfigurable without this entity.
  • Note:shadow_control is deprecated and non-functional in CS:GO engine branch, and has been succeeded by env_cascade_light. Use that entity instead.
• env_sun places a glowing sprite in the skybox to represent the Sun's apparent position in the sky. It has no effect on lighting aside from this.
• env_cascade_light casts harsh, real-time shadows onto the map, usually copying settings from the light_environment entity (in all games since )(also in ).
• newLight_Dir places godrays radiate from disk/circle in the skybox; does not contribute any actual lighting (the lighting code is disabled) (only in ).
• light_deferred_global casts dynamic shadows and lighting similar to env_cascade_light (only in )(also in ).

Explanation

To make sense of it all, just make sure you have only one of each of these entities in your map, and that the Pitch and Yaw <angles> are set the same for all three of them. (Pitch is equivalent to the Sun's angle of elevation from the ground, and Yaw is its compass bearing.)

These lighting settings—direction, color, brightness, etc.—are fairly specific to the actual image used for the 2D skybox. The List of skies article suggests some settings for official game skyboxes. The worldspawn entity defines which skybox to use. Also note that fog will look wrong if env_fog_controller's settings don't correspond to the particular skybox in use.

Note:Pitch can be overridden for light_environment and env_sun, but not shadow_control. The Pitch override also cannot be switched off and its rotation is measured counter-clockwise from the horizontal (so straight down is -90°) whereas the <angles> Pitch's rotation is clockwise (so straight down is +90°). The workaround for this is to make sure your Pitch override merely repeats the <angles> value; for example, if your shadow_control, light_environment and env_sun <angles> are "45 -60 0", set the Pitch override to "-45".

Keyvalues

Pitch Yaw Roll (Y Z X) (angles) <QAngle>

This entity's orientation in the world. Pitch is rotation around the Y axis, yaw is the rotation around the Z axis, roll is the rotation around the X axis.

This is the angle at which the Direct Sunlight enters the map through each toolsskybox brush.

Tip: Pitch is the Sun's Angle of Elevation from the ground, and Yaw is its Compass Bearing.

• _light ⇆#000000rgb(0,0,0)⇆ <integer>

Brightness : The RGB color followed by the Brightness of Direct Sunlight.

• _ambient ⇆#000000rgb(0,0,0)⇆ <integer>

Ambient : The RGB color followed by the Brightness of Diffuse Skylight.

• _lightHDR ⇆#000000rgb(0,0,0)⇆ <integer>

BrightnessHDR : This approximates Direct HDR sunlight. Can be left as default or be slightly less bright, since HDR is sometimes rendered brighter.

• _lightscaleHDR <float>

BrightnessScaleHDR : Amount to scale the Direct light by when compiling for HDR.

• _ambientHDR ⇆#000000rgb(0,0,0)⇆ <integer>

AmbientHDR : This is the Diffuse HDR light. Can be left as default or be slightly less bright.

• _AmbientScaleHDR <float>

AmbientScaleHDR: Amount to scale the Diffuse light by when compiling for HDR.

• pitch <angle>

Pitch : This value overrides the value of pitch in the keyvalue "angles". 90 is straight up, -90 is straight down.

Warning:Unfortunately Valve introduced a Pitch override parameter to the light_environment and env_sun entities, but not to shadow_control. Even more unfortunately, the Pitch override cannot be switched off and its rotation is measured counter-clockwise from the horizontal (so straight down is -90°) whereas the <angles> Pitch is rotation is clockwise (so straight down is +90°). The workaround for this is to make sure your Pitch override merely repeats the <angles> value; for example, if your shadow_control, light_environment and env_sun <angles> are "45 -60 0" set the Pitch override to "-45".

• Template:EP2 add <float>

SunSpreadAngle : The angular extent of the sun for casting soft shadows. Higher numbers are more diffuse. 5 is a good starting value for just nice blurriness. Remember: on cloudy days, the shadows will be blurred because the sunlight is being diffused by clouds. Try 90 for hazy days, and use 135 for cloudy days, rain and fog. If you're trying a night atmosphere, sometimes you'll need up to 180. You'll also have to turn down the shadow alpha in your shadow_control entity - try changing the Shadow Color variable to something such as 50 50 50.

External links

• Nodraw.net - brief explanation with screenshots of various sunspreadangle values