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Use the GDC 2021 Session Viewer to browse and sort the ever-growing list of sessions by day, time, pass type, topic, and format. All registered attendees will be able to build their personal schedule directly within the event platform, once live early July 2021. All times are listed in Pacific Time.

AI Summit: Branching Out: 'Watch Dogs Legion's' Architecture for Group AI Behaviours

Christopher Dragert, Ph.D.  (Lead AI Programmer, Ubisoft Toronto)

Patrick McKenna  (AI Programmer, Ubisoft Toronto)

Date: Monday, July 19

Time: 9:40am - 10:40am

Pass Type: All Access Pass, Summits Pass

Topic: Programming

Format: Session

Vault Recording: Video

Audience Level: N/A: I would like to deliver a virtual presentation only

In the open world of Watch Dogs: Legion, a key component of world tone is having believable AI performing realistic behaviours. While much can be accomplished using individuals, having multi-character interactions provides a richer experience. This talk will present in detail the aLiVE Group Behaviour System, a highly modular AI architecture developed at Ubisoft Toronto. This system allows for the creation of highly reactive group behaviours, used in Watch Dogs: Legion to author ID checks, extortions, crime events, hostage scenarios, protest groups, and police interactions. When the player interacts with these scenes, the group behaviour system can properly consider the group context and roles of participants to react in realistic and interesting ways.


This talk describes in detail the AI group behaviour system used in Watch Dogs: Legion. Attendees will learn how to create a highly modular scripted AI system that manages group interactions and reactions, along with how to integrate such a system into a complex open world sandbox.

Intended Audience

This talk is broadly aimed at AI programmers, designers, and technical animators. It will be especially relevant to individuals that work in the AAA space, and are interested in modular AI, scripted behaviours, open world AI design, or group AI interactions in particular.