[sourcecode language=”java”]
package
{
import flash.display.Sprite;
import flash.events.Event;
import flash.events.KeyboardEvent;
import flash.ui.Keyboard;
import flash.display.StageAlign;
import flash.display.StageScaleMode;
public class ShipSim2 extends Sprite
{
private var ship:Ship;
private var vr:Number = 0;
private var thrust:Number = 0;
private var vx:Number = 0;
private var vy:Number = 0;
public function ShipSim2()
{
init();
}
private function init():void
{
stage.scaleMode = StageScaleMode.NO_SCALE;
stage.align=StageAlign.TOP_LEFT;
ship = new Ship();
addChild(ship);
ship.x = stage.stageWidth / 2;
ship.y = stage.stageHeight / 2;
addEventListener(Event.ENTER_FRAME, onEnterFrame);
stage.addEventListener(KeyboardEvent.KEY_DOWN, onKeyDown);
stage.addEventListener(KeyboardEvent.KEY_UP, onKeyUp);
}
private function onKeyDown(event:KeyboardEvent):void
{
switch(event.keyCode)
{
case Keyboard.LEFT :
vr = -5;
break;
case Keyboard.RIGHT :
vr = 5;
break;
case Keyboard.UP :
thrust = 0.2;
ship.draw(true);
break;
default :
break;
}
}
private function onKeyUp(event:KeyboardEvent):void
{
vr = 0;
thrust = 0;
ship.draw(false);
}
private function onEnterFrame(event:Event):void
{
ship.rotation += vr;
var angle:Number = ship.rotation * Math.PI / 180;
var ax:Number = Math.cos(angle) * thrust;
var ay:Number = Math.sin(angle) * thrust;
vx += ax;
vy += ay;
ship.x += vx;
ship.y += vy;
var left:Number = 0;
var right:Number = stage.stageWidth;
var top:Number = 0;
var bottom:Number = stage.stageHeight;
if (ship.x – ship.width / 2 > right)
{
ship.x = left – ship.width / 2;
}
else if (ship.x + ship.width / 2 < left)
{
ship.x = right + ship.width / 2;
}
if (ship.y – ship.height / 2 > bottom)
{
ship.y = top – ship.height / 2;
}
else if (ship.y < top – ship.height / 2)
{
ship.y = bottom + ship.height / 2;
}
}
}
}
[/sourcecode]