Thing

Note: This article needs to be cleaned up. Its information may be poorly-written, erroneous, incomplete, obsolete or irrelevant to the purpose of this wiki.

In Doom, things are used to represent players, monsters, pick-ups, and projectiles. Inside the game, these are known as actors. There are three ways to get an actor into your map. Most things are actors, so the names are often used interchangeably. A few things, however, are not actors, such as player start points.

Referencing things

DoomEd numbers are the numbers used in the editor to represent an actor. When the map is loaded, an actor that corresponds to that number will be spawned at the location of that map thing. Although many actors have DoomEd numbers, not all of them do. For instance, a blue key card has a DoomEd number, but a rocket flying through the air does not.

Spawn numbers are the numbers used by specials such as Thing_Spawn to spawn actors in the game once the user has started playing the map. Although DoomEd numbers and spawn numbers both describe actors, they are not interchangeable—you must not use a spawn number on a map thing, and you must not use a DoomEd number for instance as a Thing_Spawn parameter.

Actor Names are the actual names each actor has internally (to test these you may want to try out the summon console command). These are used with the functions SpawnSpot and Spawn which allow you to spawn any actor available with Thing_Spawn and also all other actors (though some actors aren't meant to be spawned) such as cameras, scenery or whatever you might require.

If you create a new actor with the DECORATE lump, you can specify both the spawn number (SpawnID), and the DoomEd number (DoomEdNum). The name you give the new DECORATE item is also its actor name, so you can also spawn it using that.

There is also a third set of numbers used to represent actors that is only important for DeHackEd and similar. These numbers correspond to the order the actors were defined in the vanilla exe. They have no meaning outside of ZDoom's DeHackEd loader and as a result are not a property. In Strife, they were used to identify actor classes in conversations, but ZDoom turned these into the ConversationID property because identical actors had different numbers in the different versions of Strife available.

Specification (Doom format)

Bytes	Data type	Description	Notes
0-1	Signed short	X position
2-3	Signed short	Y position
4-5	Unsigned short	Angle	0=East, 45=NE, 90=North 135=NW, 180=West, 225=SW, 270=South
6-7	Unsigned short	Type	See the list of standard editor numbers
8-9	Unsigned Short	Spawn flags

Specification (Hexen format)

Bytes	Data type	Description	Notes
0-1	Unsigned short	Thing ID	This value is used for scripts and specials
2-3	Signed short	X position
4-5	Signed short	Y position
6-7	Signed short	Z position
8-9	Unsigned short	Angle	0=East, 45=NE, 90=North 135=NW, 180=West, 225=SW, 270=South
10-11	Unsigned short	Type	See the list of standard editor numbers
12-13	Unsigned short	Spawn flags
14	Unsigned byte	Action special	An action to be executed when this thing is destroyed or picked up
15	Unsigned byte	Action argument 1
16	Unsigned byte	Action argument 2
17	Unsigned byte	Action argument 3
18	Unsigned byte	Action argument 4
19	Unsigned byte	Action argument 5

Spawn flags

Thing Flags are in this format for Hexen/ZDoom:	Thing Flags are in this format for Doom:	Thing Flags are in this format for Strife:
Bit Hex Description 0 0x0001 Thing is on Skill levels 1 & 2 1 0x0002 Thing is on Skill level 3 2 0x0004 Thing is on Skill levels 4 & 5 3 0x0008 Thing's AMBUSH flag is set 4 0x0010 Thing is DORMANT until activated 8 0x0100 Thing is in single player 9 0x0200 Thing is in coop 10 0x0400 Thing is in deathmatch 11 0x0800 Thing is 25% translucent 12 0x1000 Makes the thing invisible 13 0x2000 Friendly monster 14 0x4000 Thing stands still (only useful for specific Strife monsters or friendlies)	Bit Hex Description 0 0x0001 Thing is on Skill levels 1 & 2 1 0x0002 Thing is on Skill level 3 2 0x0004 Thing is on Skill levels 4 & 5 3 0x0008 Thing's AMBUSH flag is set 4 0x0010 Thing is not in single player 5 0x0020 Thing is not in deathmatch 6 0x0040 Thing is not in coop 7 0x0080 FRIENDLY monster	Bit Hex Description 0 0x0001 Thing is on Skill levels 1 & 2 1 0x0002 Thing is on Skill level 3 2 0x0004 Thing is on Skill levels 4 & 5 3 0x0008 Thing stands still (only useful for specific Strife monsters) 4 0x0010 Thing is not in single player 5 0x0020 Thing's AMBUSH flag is set 7 0x0080 FRIENDLY monster 8 0x0100 Thing is 25% translucent 9 0x0200 Makes the thing invisible