Ultimate Game Design : Building game worlds

Building Game Worlds
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U L T I M A T E G A M E D E S I G N
Counter
}
// Make "region2" rain more heavily at level "50"
weatherSystem.startRain(region2, 50);
A counter trigger simply counts down a number of time units and then launches its
event. The amount of time the counter trigger waits to launch an event is set in its
properties. This allows you to play with timing. How long should you give players to
flee? How long until the next event? So, if a player trips a counter trigger, they might
have a ten-second head start before a gigantic robotic spider is loosed into the level
after them. You’ll also want to tune the attack speed and attack properties of the spider
to give the players a chance.
You might use a counter trigger on one side of the map to launch a counter trigger
on the other side of the map. This allows for a “popcorn popping” effect as counter
triggers launch their events across a map. These are very useful for action games and
environmental shooters.
This script sample shows how you might warn the player that they have invaded
the robotic spider’s nesting point, give the player a chance to flee, and then set the spider
hunting after the player:
Material
// JavaScript sample of "counter" trigger support
if(player.intersects(spider.getBoundary())) {
alertUser(spiderWarningText);
waitSeconds(10);
spider.startHunting();
}
A material trigger, when tripped by a player location trigger (remember the “popcorn”
effect), changes texture information in a scene. For instance, a player may have tripped
a location trigger that causes an ice crystal formation to rise out of the ground covered
by a dusty particle effect. As the ice crystals rise, light triggers are tripped and the light
in the room intensifies (for dramatic and visual bang!).
Wouldn’t it be nice to have the wall textures or wall materials somehow account for
all the light bouncing off these cool ice crystals? Well, you could make an animated
“light reflection” version of the wall texture and display it when the material trigger
is tripped. Now, as the ice crystals rise, the animated light reflections on your custom
wall texture or material are displayed! Very cool. If no new “material” information is
given to the material trigger, it commonly does nothing. It doesn’t know what to do if
it doesn’t have new material information.