Thing executed specials

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Thing Executed Specials

Things can execute all the Action Specials ZDoom offers, however, certain things execute them in certain ways (or when a certain action happens to them). Here's a listing of what I currently know.

Shootable Things
This includes monsters as well as breakable items such as the clay pots in Hexen. These things will execute their action special when their health reached less than or equal to zero (in other words, when they die or break open).

Pickable Items
This includes items such as weapons, health pickups, keycards, ammo, powerups and DECORATE pickups. These items will execute their special when they are picked up.

Patrol Special
This is a fairly obscure thing that will execute its special when the patrol point with the same TID is reached by the thing on the patrol route. For instance, if you have an imp patrolling from patrol point 7 to patrol point 8 and you have a patrol special thing with a tid of 8 on the map somewhere then when that imp reaches patrol 8, whatever special is attached to the patrol special will execute.

Interpolation Special
On a very similar note the Interpolation Special thing will do the same exact thing as a Patrol Special except that it works for things following a path of interpolation points (using an actor mover, a moving camera or another type of path follower).

Sector Action Things
There are eleven total of these and each will execute their attached special when a certain action occurs. Here's a list:

Actor Enters Sector - (DoomEdNum 9998)
Actor Hits Ceiling - (DoomEdNum 9996)
Actor Hits Fake Floor - (DoomEdNum 9989)
Actor Hits Floor - (DoomEdNum 9999)
Actor Leaves Sector - (DoomEdNum 9997)
Eyes Go Above Fake Ceiling - (DoomEdNum 9982)
Eyes Go Above Fake Floor - (DoomEdNum 9992)
Eyes Go Below Fake Ceiling - (DoomEdNum 9983)
Eyes Go Below Fake Floor - (DoomEdNum 9993)
Player Uses Sector - (DoomEdNum 9995)
Player Uses Wall - (DoomEdNum 9994)

In the case of the first five things, if it's Ambush flag is set then a monster can also trigger it, and if it's flagged to be dormant then a projectile can also trigger it. The second four are used in conjunction with Transfer_Heights and only work for the player. The final two also work only for the player and must be executed within range of a linedef without a special. In the case of thing 9995 the player must be in the same sector as the sector action thing and just press used from anywhere within the sector, but out of range of a wall with a special.

Note that, as with non-open/enter scripts, certain specials such as Transfer_Heights, can not be attached to a thing (these are action specials that are only good at level initialization and cannot be activated later during play).