Game Development Reference
In-Depth Information
Chapter 8. Attacking
Fighting is an important part of a game's AI. For many games, fighting with the player
is the main game mechanic and the most noticeable AI in the game. We will discuss
the common methods for attack AI, how to make an enemy character chase and at-
tack the player, and then have the enemy character take cover and hide from the
player.
In this chapter, you will learn about:
• Designing attack AI in RAIN 2.1.4
• Creating basic chase attack AI
• Creating and covering attack AI
• Having AI attack in groups
An overview of attack AI
Attack AI is a large and much studied subject. When you start dealing with things
such as different attack moves based on different player actions or having enemies
coordinate attacks, the AI can become quite complex. However, designing good AI
that attacks is the same as designing for other AI scenarios we have looked at so far
inthis topic. First, weneedsensorsfor ourAI characters to perceivegameevents and
to create aspects in the game world, tagging what they can sense. Then, we define
behavior trees for the characters, directing them to change actions based on sensor
response or other game states, such as running out of ammo. Defining different be-
haviors is the main part of setting up attack AI.
We'll look at two foundational AI attack behaviors in our demos in this chapter. The
first will use multiple sensors on the AI to determine when to chase and when to stop
and attack. The second behavior we will look at is the duck and cover type, where
the enemy attacker will retreat to a safe position after attacking, and this is based on
set navigation points. These are both best illustrated through demos, so let's start one
now.
