WarpZoneInfo

A Warp Zone is a zone that behaves in a very similar manner to a teleporter. The big difference between the two is that you can see through a warp zone to the other side. This enables sections of a level to be seamlessly joined together even though they are separated in space (or disjoint). Warp Zones need to be placed with care for a number of reasons:

• Hit scan weapons (the minigun, the sniper rifle) will not fire through a Warp Zone so avoid using them in long corridors. There's nothing worse than shooting at someone the other end of the corridor when you bullets simply vanish mid-corridor.
• They can make your level layout very confusing as you are not bound by the normal rules of space.
• Avoid placing Warp Zones such that the player could see through more than one. You risk some strange hall of mirrors type effects and your framerate will plummet.
• Warp Zones must be at least 72 units deep if you want players to be able to travel through them, but 128 units is reccomended. If you only want to be able to see "through" the warp zone and travel through it is not requires, then you can make it as shallow as you want. When pathing the zone place the final PathNode as deep into the Warp Zone as you can - this tends to prevent bots getting stuck in the Warp Zone itself.
• Do not place any semi-solids or actors within your warp zone – it should be completely bare apart from the WarpZoneInfo object itself. Strange things happen when you do from relatively benign HOM effects through to map crashes.
• Both Warp Zones should be the same shape with the same textures, otherwise the transition will not be very seamless when you walk through the warp zone.

The Warp Zones are tied together by matching the OtherSideURL and the ThisTag properties of the Warp Zone. UT's DM-Fractal uses a Warp Zone in the pit that opens when the lower switches are hit.

The diagram below shows a small example level that contains four Warp Zones (or two pairs). One pair of Warp Zones link to each other horizontally, and the other pair of Warp Zones link to each other vertically, from bottom to top.

This is the front view of a level with 4 Warp Zones on it. And yes it is possible to shoot yourself in the back with the rocket launcher in the level.

Properties

bNoTeleFrag

Set this to true if you want people travelling through the warp zone to telefrag each other. Since this rather spoils the effect of the Warp Zone it's best left to false.

OtherSideURL

This property determines the destination Warp Zone. It should contain the same value as the target Warp Zones ThisTag property.

ThisTag

This property is the ID of the Warp Zone. All Warp Zones linking to this Warp Zone will have their OtherSideURL property set to the value of this property.

Destinations

A set of up to 8 destination tags. When the WarpZone is triggered it will switch the warpzone view on the fly. The order they switch through is bottom to top in the list, ie 7-0. Setting the warpzone's own tag as one of the destination warpzones will in effect turn off the warpzone too.

Usage

Portal Orientation

Warp zones will change the orientation of the player, but not necessarily in the way you expect. The warp zone rotates the entire coordinate system. In short: if the player enters the departure warp zone looking at the front side of the surface, they must leave the arrival warp zone with the rear side of the surface behind them. Or to put it another way: imagine the map being ripped apart, with the two zone portal surfaces being brought to coincide with each other – they should be facing the same way. Now, with portals where the player falls into the floor and then drops from the ceiling, or walks East in to the warp zone and comes out still walking East, this is a no-brainer: just add the two portals one after the other, without rotating the sheet red builder brush. In other situations, the mapper is faced with some problems in determining which way to orient the sheets:

• the surfaces are two-sided
• they're only visible if the camera is in the world volume and realtime preview is off
• you can't tell which way a surface is facing anyway

Trial and error is one option. Another is to use a texture which displays fonts. Editor.Bad is good, as it's already loaded. For a warp zone pair, you need to make sure that when you look at each portal from the main map area, one reads correctly and the other is mirrored.

Skybox

Warpzones and skyboxes don't mix, it seems. If both a warp portal and a surface displaying the skybox are visible, the engine can have problems drawing polys correctly.

The technicalities are this: if a poly P1 is visible through the warp portal Pw and overlaps a Fake Backdrop poly P2, then portions of P1 will be drawn within Pw and ALSO within P2.

Note on Warpzone Destinations

If you leave the OtherSideURL blank and only have entries in the Destinations, the warpzone will start out deactivated, ie it's just a normal closet style room you can walk in and out of as you would any normal room.

Once you trigger the warpzone however, the first destination view appears and you can then walk into and out of that view. Press the trigger again and another view replaces that one.

If you set one of the destinations to point to itself, ie. the warpzone's tag is me and one of the Destinations is set to me, then when this destination is triggered on, the warpzone is deactivated, turning it into a normal room again.

See the demo map here:

http://www.doogle.co.uk/private/warpzonechanger.zip

Warp Zone Spanning Levels

In theory, you can specify another level's URL as the destination/OtherSideURL of the Warp Zone. I haven't had any success with this though.

Warp Zones in UT2003 and Later

Apparently, Warp Zones have been removed from UT2003 and later engine versions due to incompatibility with some of the newer 16-bit graphics features. They still appear to teleport, but the zone portals become opaque. Setting a transparent texture to them to overcome the opacity results in a Hall of Mirrors effect.

See also [Rachel's tutorial]