A_Look

Zombiemen at the start of MAP01 in their spawn state, cycling through A_Look to try to locate a target.

A_Look is a code pointer used in the normal animation for various monsters.

A_Look scans the immediate area for targets (i.e. players to attack). Most monsters are initially spawned cycling through a series of states that repeatedly call A_Look. The following strategies are used to find a target:

1. The sound target of the sector that the monster is standing in is checked; if the player fires a weapon, the monster will wake up and attack, unless the monster has the ambush/deaf flag set.
2. The monster checks if it can see any players who are still alive and still in the game. Players must be in the 180 degree field in front of the monster.

When a target is located, the monster plays its "see sound" (for example, in the case of an imp that is DSBGSIT1 or DSBGSIT2) and jumps to the "see state" that will lead it to attack the player by calling A_Chase.

The following call graph shows some of the internals of the A_Look code pointer:

Uses

The A_Look code pointer appears in the following states in Doom's state table:

Frame number	Doom internal name	Use
174	S_POSS_STND	normal animation for the zombieman
175	S_POSS_STND2	normal animation for the zombieman
207	S_SPOS_STND	normal animation for the shotgun guy
208	S_SPOS_STND2	normal animation for the shotgun guy
241	S_VILE_STND	normal animation for the arch-vile
242	S_VILE_STND2	normal animation for the arch-vile
321	S_SKEL_STND	normal animation for the revenant
322	S_SKEL_STND2	normal animation for the revenant
362	S_FATT_STND	normal animation for the mancubus
363	S_FATT_STND2	normal animation for the mancubus
406	S_CPOS_STND	normal animation for the heavy weapon dude
407	S_CPOS_STND2	normal animation for the heavy weapon dude
442	S_TROO_STND	normal animation for the imp
443	S_TROO_STND2	normal animation for the imp
475	S_SARG_STND	normal animation for the spectre and demon
476	S_SARG_STND2	normal animation for the spectre and demon
502	S_HEAD_STND	normal animation for the cacodemon
527	S_BOSS_STND	normal animation for the baron of Hell
528	S_BOSS_STND2	normal animation for the baron of Hell
556	S_BOS2_STND	normal animation for the Hell knight
557	S_BOS2_STND2	normal animation for the Hell knight
585	S_SKULL_STND	normal animation for the lost soul
586	S_SKULL_STND2	normal animation for the lost soul
601	S_SPID_STND	normal animation for the spiderdemon
602	S_SPID_STND2	normal animation for the spiderdemon
632	S_BSPI_STND	normal animation for the arachnotron
633	S_BSPI_STND2	normal animation for the arachnotron
674	S_CYBER_STND	normal animation for the cyberdemon
675	S_CYBER_STND2	normal animation for the cyberdemon
701	S_PAIN_STND	normal animation for the pain elemental
726	S_SSWV_STND	normal animation for the Wolfenstein SS
727	S_SSWV_STND2	normal animation for the Wolfenstein SS
784	S_BRAINEYE	normal animation for the monster spawner

Example

The following is an example of how to set the A_Look code pointer in a DeHackEd file:

Pointer 21 (Frame 34)
Codep Frame = 784

Or using BEX syntax:

[CODEPTR]
Frame 1234 = Look

External links

• A_Look in the Doom source code.
• A_Look at the ZDoom wiki
• Look at the Eternity Engine wiki