Ultimate Game Design : Building game worlds

If (cave_guard.isDisturbed()) {
playMessage(text1.txt);
waitForUser();
playMessage(text2.txt);
waitForUser();
playMessage(text3.txt);
waitForUser();
}
In this example, the cave guard is disturbed and gives messages to the player, while
waiting for the player to acknowledge receipt of the given messages. If the player
came back to try to talk to the cave guard again after seeing the first three messages,
you might want the cave guard to give random responses this time. You could do this
by simply extending your script so that any contact after the first or initial contact
would give random responses loaded into a file for playback to the player.
Shooter Flying Patterns
C H A P T E R 6
For arcade-style shooting games, enemies often attack in different formations,
speeds, and flying patterns. These kinds of behaviors can be edited via a script system
as well. Let’s look at an example.
Suppose you’re building a shooter. Enemies might simply attack from the far right
and move toward the left of the screen. This is the formula for almost every classic
side-scrolling shooter. Maybe we want to control the behaviors of those enemy attack
formations. Here’s where I hope we all paid attention in math class! D’oh! Games are
pure math in motion. How does all of this amazing and brilliant 3-D manipulation
happen? It’s solid math, toes to top hats.
Scripting has become a very important part of the designer’s role on a development
team, so knowing (at the very least) some basic programming and math is extremely
helpful here. If your basic programming skills are rusty or nonexistent, download a
free version of a JavaScript editor at (www.ngweb.biz/software/djsedit.shtml) and
start experimenting.
Here’s a simple script for defining the attack behavior of an enemy actor (for example,
a Martian horde or evil flying donut) called enemyactor:
function moveEnemy() {
enemyactor.moveLeft();
// Scale sine wave by 100 and add 240 to center
// on a 640x480 screen
var x = enemyactor.getX()%360;
enemyactor.setY(100*sin(x*4)+240);
}
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Scripting Action Events