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From Unreal Wiki, The Unreal Engine Documentation Site
The built-in Unreal class for defining properties of zones. If you place one ZoneInfo actor in a zone you have partioned, the ZoneInfo defines the properties of the zone. Zones without a ZoneInfo actor take their properties from the LevelInfo actor.
This may seem obvious, but after adding a new ZoneInfo actor, the map geometry must be rebuilt for that actor's properties (e.g. ZoneLight) to take effect. Aftwards, you can change the ZoneInfo properties without rebuilding.
 ZoneInfo Group
- bool bClearToFogColor
- Clear to fog color if distance fog is enabled. Use this to prevent HOM effects in the distance fog. Disable this if your distance fog end is never seen
- bool bDistanceFog
- There is distance fog in this zone. See Distance Fog.
- bool bSoftKillZ
- 2000 units of grace for KillZ unless land.
- bool bTerrainZone
- There is terrain in this zone.
- float KillZ
- Any actor falling below this height falls out of the world. For Pawns this means they die, other actors usually get destroyed. The LevelInfo's KillZ shows as a red line in side-view orthogonal UnrealEd Viewports.
- eKillZType KillZType
- Specifies the type of KillZ effect to apply.
- string LocationName (localized)
- A description of this zone. This is what appears on the scoreboard in team games as the location of players. You can use Volumes to create descriptions for a part of a zone.
- name ZoneTag
- Used only in combination with a ZoneTrigger. All other actors and engine features use the Tag.
 ZoneLight Group
See Zonelight for more on this.
- byte AmbientBrightness
- byte AmbientHue
- byte AmbientSaturation
- float DistanceFogBlendTime
- color DistanceFogColor
- The color of the Distance Fog.
- float DistanceFogEnd
- The distance from the player in which the distance fog completly obscures the world.
- float DistanceFogStart
- The distance from the player in wich the distance fog starts to obscure the world.
- Texture EnvironmentMap
- float TexUPanSpeed
- float TexVPanSpeed
 ZoneSound Group
- I3DL2Listener ZoneEffect (editinline)
- Environmental sound settings used in this zone. This will only have an effect if the game uses 3D hardware audio with EAX.
 ZoneVisibility Group
- bool bLonelyZone
- This zone is the only one rendered when viewing from inside this zone. This zone is never rendered if viewing from another zone. This also includes skyboxes, so an outdoor level with only one zone plus a skybox should not use this.
- array<ZoneInfo> ManualExcludes (editinline)
- Used for manually specifying zones that are never visible from this zone. This is highly useful for framerate optimization if there are zones in your map that in theory need to be rendered, but are practically not visible from any point of this zone.
 UnrealScript-Only Properties
- vector AmbientVector
- SkyZoneInfo SkyZone
- Optional sky zone containing this zone's sky.
- array<TerrainInfo> Terrains (const)
 Iterator Functions
 Other Functions
- LinkToSkybox ( ) [simulated]
- This function is called from PreBeginPlay and initialises the link to the Sky Zone for this zone. The SkyZoneInfo object linked to is determined by the detail settings on the client machine (if there is more than one).
- ActorEntered (Actor Other)
- This event fires whenever an actor enters the zone. It is responsible for posting any event specified by the ZonePlayerEvent property by calling the Trigger function. The function also applies any zone physics to objects with physics of PHYS_Projectile or objects of type Effects.
- ActorLeaving (Actor Other)
- This event fires whenever an actor leaves the zone. It is responsible for posting any event specified by the ZonePlayerEvent property by calling the UnTrigger() function.