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Gerard Escudero, 2020

.footnote[source ]

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• .cyan[Introduction]

• Formation Motion

• Waypoint Tactics

• Tactical Analysis

• Tactical Pathfinding

• References

General plan to achieve a goal (long time).

Example:
Planning where to send the troops to win the war.

Specific plan to achieve a particular goal (part of a strategy).

Example:
How soldiers should run in a zig-zag pattern to decrease the chance of being shot.

.footnote[.red[Source]: Diffen (Strategy vs Tactic)]

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• .brown[Introduction]

• .cyan[Formation Motion]

• Waypoint Tactics

• Tactical Analysis

• Tactical Pathfinding

• References

.cols5050[ .col1[ For simple formations.

• .blue[Formation]: set of slots

• .blue[Slot]: location for an agent

  • 1 slot leader
  • rest of slots follow the leader
    $p_s=p_l+\Omega_l r_s$
    $\Omega_s=\Omega_l+\omega_s$
    
    $s$: slot
    $l$: leader
    $p$: position
    $\Omega$: orientation
    $r$: position to leader
    $\omega$: orientation to leader ] .col2[

• video / code / download
  Other formations may require the rotation of the followers!

• .blue[Scalable Formations]

  • Depends on the number of members.
  • Example: defensive circles

• .blue[Emergent Formations]

  • Not all the members follow the leader (cascade)
  • Example: wedge formation ]]

• .blue[Slot Roles] are the typical RPG formations, in which every layer has a role:

  1. Melee warriors
  2. Arquers and Missile Magicians
  3. Magic and Healers

• They might need rearguard layers.

• Given a fixed slot structure, an assignment of units has to be given:

.cols5050[ .col1[ .center[

• Genetic Algorithm

• Fitness: $\sum_i cost_i$

]]

• Given a set of units, build a proper slot structure. .cols5050[ .col1[ ] .col2[ ]]

• Video

• Spawner / download

• Follower / download

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• .brown[Introduction]

• .brown[Formation Motion]

• .cyan[Waypoint Tactics]

• Tactical Analysis

• Tactical Pathfinding

• References

.blue[Tactical locations or waypoints]:

• defensive locations, cover points, shadows...

• A location can be a compound tactic: set of primitive tactics
  Example: cover / shadow

.blue[Using tactical locations]:

• Previous algorithms: FSM, BTs, GOAP...

.blue[Generation of properties]:

• Manually: level designer

• Automatic: raycast (visibility, cover), light maps (shadow)...

.blue[Generation of waypoints]:

• Watching human players

• Waypoint Grids: test possible locations and choose the bests

.center[ ]

.cols5050[ .col1[

• Video ] .col2[
• FindClosestCop / download
• Cop / download ]]

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• .brown[Introduction]

• .brown[Formation Motion]

• .brown[Waypoint Tactics]

• .cyan[Tactical Analysis]

  • .cyan[Influence maps]

  • Terrain Analysis

• Tactical Pathfinding

• References

Track of current military influence of each location.

.blue[Influence]:

.cols5050[ .col1[ $$I_d=\frac{I_0}{1+d}$$ ] .col2[ $I_0$: power of the unit

$d$: distance to the unit ]]

.blue[Applications]:

• Safe areas, areas to avoid, weakest border...

• Plan attack locations or movement guide

.blue[Dealing with unknowns]:

• Risk of underestimating forces (fog-of-war)

• Prediction of the enemy forces (Machine Learning)

Influence maps by Anomalous Underdog

• Video / Reference

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• .brown[Introduction]

• .brown[Formation Motion]

• .brown[Waypoint Tactics]

• .cyan[Tactical Analysis]

  • .brown[Influence maps]

  • .cyan[Terrain Analysis]

• Tactical Pathfinding

• References

Extracting useful data from the structure of the landscape.

• Covers, shadows, visibility...

• Algorithm: visite locations, calculate and annotate.

• Situations may change fast and they can have a high cost.

.cols5050[ .col1[ ] .col2[ Killzone's AI: dynamic procedural combat tactics

.blue[Initial situation]
(with legends)

]]

.cols5050[ .col1[ .blue[a) Distance nearby points]

.blue[c) Line-of-fire secondary threats]

] .col2[ .blue[b) Line-of-fire primary threat]

.blue[d) Preferred fighting range]
]]

.footnote[Killzone's AI: dynamic procedural combat tactics]

.blue[e) Adding all annotations yields best position]

.center[ ]

.footnote[Killzone's AI: dynamic procedural combat tactics]

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• .brown[Introduction]

• .brown[Formation Motion]

• .brown[Waypoint Tactics]

• .brown[Tactical Analysis]

• .cyan[Tactical Pathfinding]

• References

.blue[Is shortest path the best path?]

.red[*]

.blue[Connection cost function]:

.cols5050[ .col1[ $$C=D+\sum_i w_iT_i$$ ] .col2[ $D$: distance
$w$: weight
$T$: tactic ]]

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• .brown[Introduction]

• .brown[Formation Motion]

• .brown[Waypoint Tactics]

• .brown[Tactical Analysis]

• .brown[Tactical Pathfinding]

• .cyan[References]

• Straatman, van der Sterren & Beij. Killzone's AI: dynamic procedural combat tactics.

• Ferdinand Joseph Fernandez. Influence Maps Unity 3d, Anomalous Underdog, 2012.

• Ian Millington. AI for Games (3rd edition). CRC Press, 2019.

• Ammobox Studios. FPS/RTS Tactical AI in Unreal Engine 4.0, 2014.

• Soren Johnson. Playing to Lose: AI and "Civilization", 2010.

• Damián Isla. Building a Better Battle: The Halo 3 AI Objectives System, audio, 2008.

• Alex J. Champandard. The Core Mechanics of Influence Mapping, video, 2011.