Creating a Viral Game: Tunnel Panic - The Essential Guide to Flash Games - page 611

private var playfieldminX:int = 0;
private var playfieldmaxX:int = 599;
private var playfieldminY:int = 21;
private var playfieldmaxY:int = 378;

//obstacles
private var obstaclePool:Array = [];
private var obstacles:Array = [];
private var tempObstacle:Bitmap;
private var obstaclePoolLength:int = 200;

//game play
//how long to wait before increasing obstacle difficulty
private var obstacleUpgradeWait:int = 10000;
private var lastObstacleUpgrade:int;

//obstacle frequency
private var lastObstacleTime:int;
private var obstacleDelay:int = 800;
private var obstacleDelayMin:int = 50;
private var obstacleDelayDecrease:int = 150;

//center obstacles
private var centerFrequency:int = 15;
private var centerHeight:int = 10;
private var centerWidth:int = 15;

//obstacle height
private var obstacleHeightMin:int = 40;
private var obstacleHeightMax:int = 60;
private var obstacleHeightLimit:int = 120;
private var obstacleHeightIncrease:int = 20;

//obstacleSpeed
private var obstacleSpeed:int = 6;
private var obstacleSpeedMax:int = 12;

//obstacleColors
private var obstacleColors:Array = [0xffffff, 0xff0000, 0x00ff00, 0x0000ff, 0x00ffff,

0xffff00, 0xffaaff, 0xaaff99, 0xcc6600];
private var obstacleColorIndex:int = 0;

private var gravity:Number = 1;

//exhaust blit canvas
private var backgroundBitmapData:BitmapData = new BitmapData(580, 400, false, 0x000000);
private var canvasBitmapData:BitmapData = new BitmapData(580, 400, false, 0x000000);
private var canvasBitmap:Bitmap = new Bitmap(canvasBitmapData);
private var blitPoint:Point = new Point(0, 0);

private var exhaustPool:Array = [];
private var exhaustParticles:Array = [];
private var tempExhaustParticle:BasicBiltArrayParticle;
private var exhaustPoolLength:int = 30;
private var exhaustLength:int;