Game Development Reference
In-Depth Information
lastTime = getTimer();
systemFunction();
frameCounter.countFrames();
}
The
Main.as
class for each game will override the
systemGamePlay
state function from
GameFrameWork
and pass this
timeDifference
as well as the
paused
variable (used to pause the
game if set to
true
) into the
BlasterMines
runGameTimeBased
function. This is the new function
that we will add to the
Game
base class. Here is an example of that function from the
Main.as
that
will we will create for
BlasterMines
:
override public function systemGamePlay():void {
game.runGameTimeBased(paused,timeDifference);
}
We will be creating this
runGameTime
-based function in the
Game
base class, and we will override it
in each game that needs to implement this timer. The
runGameTimeBased
function in
BlasterMines.as
will look like the following:
override public function
runGameTimeBased(paused:Boolean=false,timeDifference:Number=1):void {
if (!paused) {
systemFunction(timeDifference);
}
}
This function is part of the BlasterMines.as internal state machine. The systemFunction will
reference the current state function. These functions must accept in the paused and
timeDifference values. Here is an example of the BlasterMines.as systemGamePlay function.
Notice that the pause functionality is applied in the previous runGameTimeBased function, so
systemGamePlay will not be called if the paused value is true.
private function systemGamePlay(timeDifference:Number=0):void {
update(timeDifference);
checkCollisions();
render();
updateScoreBoard();
checkforEndLevel();
checkforEndGame();
}
The update function for Blaster Mines must accept in the
timeDifference
value. Here is a snippet
of this function for demonstration:
private function update(timeDifference:Number = 0):void {
//time based movement modifier calculation
var step:Number = (timeDifference / 1000)*timeBasedUpdateModifier;
trace("timeDifference= " + timeDifference);
trace("timeDifference/1000=" + String (timeDifference / 1000));
trace("timeBasedUpdateModifier=" + timeBasedUpdateModifier);
trace("step=" + step);
…
