From Valve Developer Community
A brush entity that can be toggled on/off. When off, the brush will be non-solid and invisible. Does not cast lightmap shadows.
Bug: Using this entity with the Player Clip texture can cause the map to crash during compile
- Minimum Light Level
- The minimum level of ambient light that hits this brush.
- Entity Scripts
<scriptlist>(New with Left 4 Dead 2)
- Space delimited list of VScript files (without file extension) that are executed after all entities have spawned. The scripts are all executed in the same script scope, later ones overwriting any identical variables and functions.
- Script think function
<string>(New with Left 4 Dead 2)
- Name of a function in this entity's script which will be called automatically every 100 milliseconds (ten times a second) for the duration of the script. It can be used to create timers or to simulate autonomous behavior. The return value (if present) will set the time until the next call. Note:Try to avoid expensive operations in this function, as it may cause performance problems.
- Render Mode (rendermode)
- Set a non-standard rendering mode on this entity.
- Render FX / Transparency (0 - 255) (renderamt)
- Transparency amount, requires a Render Mode other than Normal. 0 is invisible, 255 is fully visible.
- Render Color (R G B) (rendercolor)
- Color tint.
- Disable Receiving Shadows (disablereceiveshadows)
- Prevent the entity from receiving shadows on itself.
- Render FX (renderfx)
- Preset pattern of appearance effects.
- Global Entity Name
- Name by which this entity is linked to another entity in a different map. When the player transitions to a new map, entities in the new map with globalnames matching entities in the previous map will have the previous map's state copied over their state.
- Disable shadows
- Prevent the entity from creating cheap render-to-texture shadows. Does not affect shadow mapping.
- Disable ShadowDepth
<boolean>(New with Portal 2)
- Used to disable rendering into shadow depth (for projected textures) for this entity.
- Projected Texture Cache
<choices>(New with Portal 2)
- Used to hint projected texture system whether it is sufficient to cache shadow volume of this entity or to force render it every frame instead.
- 0 : Default
- 1 : No cache - render every frame
- 2 : Cache it - render only once
- 1 : Starts Invisible
- Toggle the brush on/off. When off, the brush will be non-solid and invisible.