Laying The Groundwork for Flak Cannon - The Essential Guide to Flash Games - page 167

so image still exists. Also, we need currentImageIndex , which holds the index of the images array
that we are current showing. We also need a finished Boolean, so FlakCannon can tell when the
animation is complete and can start the process to remove it from the screen. frameCounter is
used to define the number of frames that have passed since we have changed images. We use
this in conjunction with frameDelay to define the length of the animation. Finally, we have another
new variable named hits , it's a counter that we increment each time a plane is destroyed by this
Flak explosion. Keeping track of hits allows us to give the player bonus points for destroying
more than one plane with a Flak explosion. After these new variables, we have to embed the Flak
explosion frames for Flex.
public var images:Array;
public var image:Bitmap;
public var currentImageIndex:int = -1;
public var finished:Boolean;
private var frameCounter:int = 0;
private var frameDelay:int = 2;
public var hits:int;
/*
//**Flex Framework Only
[Embed(source = "assets/flakassets.swf", symbol="Exp1Gif")]
private var Exp1Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp2Gif")]
private var Exp2Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp3Gif")]
private var Exp3Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp4Gif")]
private var Exp4Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp5Gif")]
private var Exp5Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp6Gif")]
private var Exp6Gif:Class;
[Embed(source = "assets/flakassets.swf", symbol="Exp7Gif")]
private var Exp7Gif:Class;
*/
Since we do not need to move Flak , the constructor simply sets hits to 0 and calls init() . hits
is a simple counter that we will use for scoring. Since a Flak explosion does not disappear when
it hits an Enemy , it can effectively destroy many planes. Hits will be used to keep track of the
number of Enemy planes that this Flak explosion has destroyed. We will give the player a bonus
for hitting multiple Enemy objects with one Flak object.
public function Flak() {
hits = 0;
init();
}
A lot of the new interesting code for Flack lives in init() . We are going to create image as a
holder for the current Bitmap and add it to the sprite. Then, we will fill the images array with all the