使用b2DebugDraw
/// 在前面的基础加上了b2DebugDraw hellowWorld的例子也有b2DebugDraw 只不过把注释掉了
最新看帖子知道： 准确的说 ：box2d里1m 等于flash 中的31像素 而不是30像素
package {
import Box2D.Collision.*;
import Box2D.Collision.Shapes.*;
import Box2D.Common.Math.*;
import Box2D.Dynamics.*;
import Box2D.Dynamics.Joints.*;
import flash.display.Sprite;
import flash.events.Event;
import Box2D.Dynamics.Joints.*
import flash.events.MouseEvent;
public class DebugDraw extends Sprite {
private var jointDef:b2MouseJointDef;
private var joint:b2MouseJoint;
private var m_world:b2World;
private var m_timeStep:Number;
private var m_iterations:uint;
private var phsScale:uint=30;
private var AABB:b2AABB;
private var body:b2Body;
private var bodyDef:b2BodyDef;
private var gravity:b2Vec2;
private var boxDef:b2PolygonDef;
private var debugDraw:b2DebugDraw;
/*
* @author :Dream@Night~夜梦惊魂
* date :10/13/2009
*
*/
public function DebugDraw() {
m_timeStep=1.0/30.0;
m_iterations=10;
createWorld();
createGround();
createBox();
createDebugDraw();
addEventListener(Event.ENTER_FRAME,Update,false,0,true);
stage.addEventListener(MouseEvent.MOUSE_DOWN,onDown);
trace(this.getChildAt(1));//测试表明对象是否添加进舞台
stage.addEventListener(MouseEvent.MOUSE_UP,onUp);
}//增加调试状态
private function createDebugDraw():void{
debugDraw= new b2DebugDraw();
var userDataSprite= new Sprite ();
var debugSprite:Sprite= new Sprite();
debugDraw.m_sprite=userDataSprite;
addChild(debugDraw.m_sprite);
userDataSprite.addChild(debugSprite);
debugDraw.m_drawScale=30;//即 1 pixel
debugDraw.m_alpha=1;//为1时线全部显示出来 为0 ,即其透明了 显示不出线
debugDraw.m_fillAlpha=0.5;//对象的颜色显示出来的透明度 为1就不显示对象原来的颜色了
debugDraw.m_lineThickness=1.5;//线显示的粗细 。
debugDraw.m_drawFlags=0xFFFFFF;//此句很重要，有了此句，一些线才会显示出来
m_world.SetDebugDraw(debugDraw);
}
private function createWorld():void {
AABB= new b2AABB();
AABB.lowerBound.Set(-100.0, -100.0);
AABB.upperBound.Set(100.0, 100.0);
gravity=new b2Vec2(0,10.0);
//gravity.Set(0,10.0);
m_world=new b2World(AABB,gravity,true);
}
private function createGround():void {
bodyDef = new b2BodyDef();
var X:Number= 20/(phsScale*2);
var Y:Number= 700/(phsScale*2);
bodyDef.position.Set(X,Y);
boxDef = new b2PolygonDef ();
boxDef.vertexCount=4;
boxDef.density=0;
boxDef.restitution=0.4;
boxDef.friction=0.3;
boxDef.SetAsBox(30,2);
bodyDef.userData= new Ground();//Ground
bodyDef.userData.width=30*2*phsScale;
bodyDef.userData.height=2*2*phsScale;
body=m_world.CreateBody(bodyDef);
body.CreateShape(boxDef);
body.SetMassFromShapes();
addChild(bodyDef.userData);
}
private function createBox():void {
for (var i:uint=0; i<5; ++i) {
bodyDef = new b2BodyDef();
bodyDef.position.x=Math.random()*15+1;
bodyDef.position.y=Math.random();
var crate_width:Number=1.5;
var crate_height:Number=1.5;
boxDef = new b2PolygonDef();
boxDef.SetAsBox(crate_width, crate_height);
boxDef.density=1.0;
boxDef.friction=0.5;
boxDef.restitution=0.2;
bodyDef.userData = new Box();
bodyDef.userData.width=crate_width*2*phsScale;
bodyDef.userData.height=crate_height*2*phsScale;
body=m_world.CreateBody(bodyDef);
body.CreateShape(boxDef);
body.SetMassFromShapes();
addChild(bodyDef.userData);
}
}
private function onDown(e:MouseEvent):void {
var body=getBodyAtMouse();
if (body) {
// body.WakeUp();
jointDef= new b2MouseJointDef();
jointDef.maxForce =5000;//此处力设大点
jointDef.target.Set(mouseX/phsScale,mouseY/phsScale);
// jointDef.frequencyHz=10;
// jointDef.dampingRatio=0.3;
//注意：body1 body2的对象不能搞错了
jointDef.body1=m_world.GetGroundBody();
jointDef.body2=body;
jointDef.timeStep=m_timeStep;
joint= m_world.CreateJoint(jointDef) as b2MouseJoint;
/*//添加向上的冲力
var impulse:b2Vec2=new b2Vec2(0,-80);
body.ApplyImpulse(impulse,body.GetWorldCenter());
if (Math.random()<0.382) {
body.ApplyTorque(450);
} else {
body.ApplyTorque(-450);
}*/
}
}
private function getBodyAtMouse():b2Body {
var body:b2Body;
var mouseBox2dX=stage.mouseX/phsScale;
var mouseBox2dY=stage.mouseY/phsScale;
var mousePosition:b2Vec2=new b2Vec2(mouseBox2dX,mouseBox2dY);
var AABB:b2AABB= new b2AABB();
AABB.lowerBound.Set(mouseBox2dX-0.001,mouseBox2dY-0.001);
AABB.upperBound.Set(mouseBox2dX+0.001,mouseBox2dY+0.001);
var shapes:Array= new Array();
var maxCount:uint=6;
var count:int=m_world.Query(AABB,shapes,maxCount);
for (var i:uint=0; i
var shape=shapes[i] as b2Shape;
var shapeXform=shape.m_body.GetXForm();
var inside:Boolean=shape.TestPoint(shapeXform,mousePosition);
if (inside) {
body=shape.m_body;
}
}
}
return body;
}
//释放内存
private function onUp(e:MouseEvent):void {
if(joint){
trace("destroy it!");
m_world.DestroyJoint(joint);
joint=null;
}
}
//直接copy这个模板
private function Update(e:Event):void {
m_world.Step(m_timeStep, m_iterations);
//更新目标点的作用位置
if(joint){
var targetPosition:b2Vec2= new b2Vec2(mouseX/phsScale,mouseY/phsScale);
joint.SetTarget(targetPosition);
}
// Go through body list and update sprite positions/rotations
for (var bb:b2Body = m_world.m_bodyList; bb; bb = bb.m_next) {
if (bb.m_userData is Sprite) {
bb.m_userData.x=bb.GetPosition().x*30;
bb.m_userData.y=bb.GetPosition().y*30;
bb.m_userData.rotation = bb.GetAngle() * (180/Math.PI);
}
}
}
}
}
demo : http://11611.jjii.net/swf/DebugDraw.swf