Light environment: Difference between revisions

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{{tip|Pitch is the Sun's Angle of Elevation from the ground, and Yaw is its Compass Bearing.}}
{{tip|Pitch is the Sun's Angle of Elevation from the ground, and Yaw is its Compass Bearing.}}
* '''_light'''
* '''_light'''
: {{color}} {{color}} {{color}} <[[integer]]> The RGB color followed by the Brightness of ''Direct Sunlight''.
: {{color}} <[[integer]]> The RGB color followed by the Brightness of ''Direct Sunlight''.
* '''_ambient'''
* '''_ambient'''
: {{color}} {{color}} {{color}} <[[integer]]> The RGB color followed by the Brightness of ''Diffuse Skylight''.
: {{color}} <[[integer]]> The RGB color followed by the Brightness of ''Diffuse Skylight''.
* '''_lightHDR'''
* '''_lightHDR'''
: {{color}} This approximates direct [[HDR]] sunlight. Can be left as default or be slightly less bright, since HDR is sometimes rendered brighter.
: {{color}} This approximates direct [[HDR]] sunlight. Can be left as default or be slightly less bright, since HDR is sometimes rendered brighter.

Revision as of 19:28, 17 April 2008

Template:Wrongtitle Template:Base point

Entity Description

Light environment.png

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.
Toolsskybox.gif

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.
  • 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 Counter-Strike: Global Offensive)(also in Xengine).
  • newLight_Dir places godrays radiate from disk/circle in the skybox; does not contribute any actual lighting (the lighting code is disabled) (only in Xengine).
  • light_deferred_global casts dynamic shadows and lighting similar to env_cascade_light (only in Alien Swarm Deferred)(also in Lambda Wars).

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.pngNote: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".
  • The Brightness keyvalue defines the colour and intensity of the direct light coming from the Sun. Direct light is cast on every surface that can "see" the Sun.
  • The Ambient keyvalue defines the colour and intensity of the diffuse light reflected from the sky/clouds. Diffuse light is cast on every face that can "see" the sky.
  • The Pitch/Yaw/Roll (<angles>) keyvalue defines the direction of the sunlight coming into the map through the toolsskybox texture.

Keyvalues

Tip.pngTip:Pitch is the Sun's Angle of Elevation from the ground, and Yaw is its Compass Bearing.
  • _light
#000000 <integer> The RGB color followed by the Brightness of Direct Sunlight.
  • _ambient
#000000 <integer> The RGB color followed by the Brightness of Diffuse Skylight.
  • _lightHDR
#000000 This approximates direct HDR sunlight. Can be left as default or be slightly less bright, since HDR is sometimes rendered brighter.
  • _ambientHDR
#000000 This is the diffuse HDR light. Can be left as default or be slightly less bright.
  • pitch
<angle> This value overrides the value of pitch in the keyvalue "angles". 90 is straight up, -90 is straight down.
Warning.pngWarning: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".