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January 2024


is a brush entity available in all Source Source games.

English (en)
class hierarchy
CFuncAreaPortalWindow defined in func_areaportalwindow.cpp
An example of its use on d2_coast_09Half-Life 2. When the player is close to the window, the entity is inactive and the player can see through the window. When the player backs up, the objects outside are culled from the PVS and replaced with a hazy low-res texture.

It creates an areaportal that automatically closes as the camera moves away, fading a second, opaque brush in to fill the gap.

A func_areaportal_window that hides interior geometry by turning black at a distance.
Icon-Bug.pngBug:(Known to affect Half-Life 2) The dev/dev_window texture has to be on both sides of the brush, combining it with any other texture (except nodraw) will result in rendering glitches (objects popping in and out of the PVS depending on player position and view angle).


Rendered Window (target) <targetname>
The brush entity that fills the gap left by the portal when closed.
Fade Start Distance (FadeStartDist) <integer>
Distance that the fade into the Rendered Window brush entity begins. The further back the player views, the more visible the brush entity will be.
Fade End Distance (FadeDist) <integer>
Distance at which the Rendered Window is fully visible, and the portal closes.
Translucency limit (TranslucencyLimit) <normal>
Prevents the Rendered Window brush from ever going completely transparent. Useful if your rendered window uses an opaque glass material.
Foreground bmodel (BackgroundBModel) <targetname>
Optional brush entity that is drawn after the fading brush model. This model should have alpha in its textures so you can see through it.

Name (targetname) <string>
The targetname that other entities refer to this entity by.


SetFadeStartDistance <integer>
Sets Fade Start Distance.
SetFadeEndDistance <integer>
Sets Fade End Distance.

See also