Linedef type 55

An example of using a continuous ceiling mover.

Linedef type 55, Continuous Ceiling Mover, is a type of linedef special which moves the ceiling of a specified sector or an FOF vertically back and forth between two specified heights. It is identical in function to linedef type 53, except that it moves only the ceiling, rather than both the ceiling and the floor. This can be used to make crushers which smoothly change direction.

Setup

To use this effect, create two control sectors outside of your map, joined by a single linedef. The easiest way to do this is to create two small squares of equal size which share a linedef. The linedef which joins together the two control sectors should be set to have linedef type 55, and be tagged to the desired target sector(s) within the map or FOF control sector(s).

The target sector's/FOF's ceiling will first move to the ceiling height of the linedef's front control sector, then to the ceiling height of the linedef's back control sector, then to the front sector again, and so on. The length of the control linedef determines the speed of the movement; one fracunit of length equals 0.25 fracunits per tic.

It is possible to add a delay before the ceiling begins to move, by setting the time in tics in the control linedef's front texture Y offset. If you want the ceiling to delay every time before changing direction, you can do so by setting the time in tics in the control linedef's front texture X offset.

Sample

Example file: ex_ld055_continuousceilingmover.wad (MAP01)

How to use

You may load this file into your favorite map editor, such as Zone Builder. Select MAP01 as the map to load. You may also load this file in the game: Save ex_ld055_continuousceilingmover.wad into the addons folder of your SRB2 directory. Start SRB2, go to the Addons menu, and then select ex_ld055_continuousceilingmover.wad. Start the game in Single Player mode. Press the Console button (~), and type in the command MAP MAP01 to access the example map. When you load this file in the game, it replaces Greenflower Zone Act 1.