Linedef type 525

An example of using a linedef 525 on floor over floor.

Linedef type 525, Carry Objects on Ceiling (Displacement), is a type of linedef special which scrolls Objects on any tagged sector's ceiling without scrolling the sector's ceiling flat. Unlike linedef type 520, it can be specifically set to start and stop at defined intervals.

Setup

The direction of the control linedef determines the direction the Objects will be carried. The length of the linedef indicates the base carrying speed (32 fracunits of length equal one fracunit per tic), however the actual effective carrying speed is set differently as explained ahead.

On its own, this linedef will not carry Objects. Rather, the Objects move whenever either the floor or ceiling of the control sector moves, which can done by using linedef executors. The actual carrying speed is equal to the base speed × the control sector's movement speed. The direction of the carrying will be reversed if the floor or ceiling height of the control sector is lowered instead of raised.

To keep things simple and easier to control, the best thing to do is just use a base speed of 1 fracunit per tic (by giving the control linedef a length of 32 fracunits), and control the carrying speed by moving the floor or ceiling of the control sector.

If this linedef is used in conjunction with linedef type 401, any Object on the carrier will move to the specified distance. If this linedef is used in conjunction with linedef type 404, the carrier will move continuously until the control sector reaches the given ceiling height. If this linedef is used in conjunction with linedef type 407, the carrier will only work as long as the linedef executor is being continuously triggered.

If Flag [6] / Not Climbable is checked, the carrying effect is made exclusive – once an Object has been pushed by this effect, it cannot be pushed by any other pushing or carrying effect in the same tic. This is useful if the effect is applied to multiple adjacent sectors, since it would normally be applied twice when an Object crosses the border between two sectors with the effect. This flag should be checked when using the linedef special in conjunction with linedef type 64; otherwise the player will not stand still on the "moving sector".

Sample

Example file: ex_ld525_carryobjectsonceiling_displacement.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_ld525_carryobjectsonceiling_displacement.wad into the addons folder of your SRB2 directory. Start SRB2, go to the Addons menu, and then select ex_ld525_carryobjectsonceiling_displacement.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.