陈童的博客 » Archivers » Box2D » Box2DFlash 基本示例程序

From everyinch on 2011-10-02 21:57:11

Box2DFlash 基本示例程序

[code lang="as3"]package{
import Box2D.Collision.Shapes.b2PolygonShape;
import Box2D.Common.Math.b2Vec2;
import Box2D.Dynamics.b2Body;
import Box2D.Dynamics.b2BodyDef;
import Box2D.Dynamics.b2DebugDraw;
import Box2D.Dynamics.b2FixtureDef;
import Box2D.Dynamics.b2World;

import flash.display.Sprite;
import flash.events.Event;
import flash.events.TimerEvent;
import flash.utils.Timer;

[SWF(width="800",height="600",frameRate="32",backgroundColor="0x000000")]
public class First extends Sprite{
private var world:b2World;
private var timeStep:Number;
private var iterations:uint;
private var pixelsPerMeter:Number = 30;

public function First(){
createWorld();
makeDebugDraw();
createGround();
addEventListener(Event.ENTER_FRAME,onEnterframe);
var timer:Timer = new Timer(1000);
timer.addEventListener(TimerEvent.TIMER,onTimer);
timer.start();
}

private function createWorld():void{
var gravity:b2Vec2 = new b2Vec2(0.0,9.8);
var doSleep:Boolean = true;
world = new b2World(gravity,doSleep);
world.SetWarmStarting(true);
timeStep = 1.0/30.0;
iterations = 10;
}

private function makeDebugDraw():void{
var debugDraw:b2DebugDraw = new b2DebugDraw();
var debugSprite:Sprite = new Sprite();
addChild(debugSprite);
debugDraw.SetSprite(debugSprite);
debugDraw.SetDrawScale(30.0);
debugDraw.SetFillAlpha(0.5);
debugDraw.SetLineThickness(1.0);
debugDraw.SetFlags(b2DebugDraw.e_shapeBit | b2DebugDraw.e_jointBit);
world.SetDebugDraw(debugDraw);
}

private function createGround():void{
var bodyDef:b2BodyDef = new b2BodyDef();
// Body的中心点
bodyDef.position.Set(400/pixelsPerMeter,595/pixelsPerMeter);
var body:b2Body = world.CreateBody(bodyDef);
var shape:b2PolygonShape = new b2PolygonShape();
// 几何体的半宽和半高
shape.SetAsBox(400/pixelsPerMeter,5/pixelsPerMeter);
body.CreateFixture2(shape);
}

private function onTimer(e:TimerEvent):void{
var bodyDef:b2BodyDef = new b2BodyDef();
bodyDef.type = b2Body.b2_dynamicBody;
bodyDef.position.Set((Math.random()*400+120)/pixelsPerMeter,0);
bodyDef.angle = Math.random()*Math.PI;
var shape:b2PolygonShape = new b2PolygonShape();
shape.SetAsBox((Math.random()*10+10)/pixelsPerMeter,(Math.random()*10+10)/pixelsPerMeter);
var fixtureDef:b2FixtureDef = new b2FixtureDef();
fixtureDef.shape = shape;
fixtureDef.density = 1.0;
fixtureDef.friction = 0.3;
fixtureDef.restitution = 0.1;
var body:b2Body = world.CreateBody(bodyDef);
body.CreateFixture(fixtureDef);
}

private function onEnterframe(e:Event):void{
world.Step(timeStep,iterations,iterations);
world.ClearForces();
world.DrawDebugData();
}
}
}[/code]
<img class="alignnone size-medium wp-image-214" title="first" src="http://www.everyinch.net/wp-content/uploads/2011/10/first1-300x133.jpg" alt="" width="300" height="133" />[/code]

查看完整版本： Box2DFlash 基本示例程序

查看完整版本： Box2DFlash 基本示例程序