The enemies of DOOM are highly stylized, and "selling" a character's design is usually tied to the quality of animations. To achieve the desired feel, the combat AI in DOOM relies a lot on straightforward full body animations.
In this GDC 2017 talk, id Software's Jake Campbell explains a few of the techniques used to make the unique animations of DOOM in a modern game environment.
Campbell discusses how the dependency on full body animations meant that the AI animation controls needed to be more flexible and robust. He also explains the techniques that were used to make this approach feasible.
Developers may appreciate that they can now watch the talk completely free via the official GDC YouTube channel!
In addition to this presentation, the GDC Vault and its accompanying YouTube channel offers numerous other free videos, audio recordings, and slides from many of the recent Game Developers Conference events, and the service offers even more members-only content for GDC Vault subscribers.
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