#ifndef __HELLOWORLD_SCENE_H__
#define __HELLOWORLD_SCENE_H__
 
#include "cocos2d.h"
#include "cocos-ext.h"
#include "Box2D/Box2D.h"
 
 
USING_NS_CC;
USING_NS_CC_EXT;
 
using namespace std;
 
class HelloWorld : public cocos2d::CCLayer,public b2ContactListener
{
public:
	HelloWorld();
	~HelloWorld();
 
    virtual bool init();  
 
    static cocos2d::CCScene* scene();
 
	// 重写生命周期函数
	virtual void onEnter();
	virtual void onEnterTransitionDidFinish();
	virtual void onExit();
 
	// 重写CCTargetTouchDelegate
	virtual bool ccTouchBegan(CCTouch *pTouch,CCEvent *pEvent);
	virtual void ccTouchEnded(CCTouch *pTouch,CCEvent *pEvent);
	virtual void ccTouchMoved(CCTouch *pTouch,CCEvent *pEvent);
	virtual void ccTouchCancelled(CCTouch *pTouch,CCEvent *pEvent);
 
	// 重写update回调函数
	virtual void update(float delta);
 
	// 重写Bos2D监听函数
	virtual void BeginContact(b2Contact* contact);
 
    CREATE_FUNC(HelloWorld);
private:
	b2World *world;
	b2Body* groundBody;
 
private:
	void initPhysics();
	void addNewSpriteAtPosition(CCPoint &pt);
};
 
#endif // __HELLOWORLD_SCENE_H__

#include "HelloWorldScene.h"
#include "Layer.h"
 
#define PTM_RATIO 30
 
USING_NS_CC;
 
HelloWorld::HelloWorld()
{
}
 
HelloWorld::~HelloWorld()
{
	CC_SAFE_DELETE(world);
}
 
CCScene* HelloWorld::scene()
{
	CCScene *scene = CCScene::create();
	HelloWorld *layer = HelloWorld::create();
	scene->addChild(layer);
 
	return scene;
}
 
bool HelloWorld::init()
{
	if (!CCLayer::init())
	{
		return false;
	}
 
	CCSize winSize = CCDirector::sharedDirector()->getWinSize();
 
	CCSprite *sprite = CCSprite::create("HelloWorld.png");
	sprite->setPosition(ccp(winSize.width/2.0,winSize.height/2.0));
	this->addChild(sprite);
 
	// 初始化物理引擎
	this->initPhysics();
 
	//开始游戏循环
	this->scheduleUpdate();
 
	return true;
}
 
void HelloWorld::initPhysics()
{
	CCSize winSize = CCDirector::sharedDirector()->getVisibleSize();
 
	//重力参数
	b2Vec2 gravity;
	gravity.Set(0.0f,-10.0f);
	//创建世界
	world = new b2World(gravity);
	// 允许物体是否休眠
	world->SetAllowSleeping(true);
	// 开启连续物理测试
	world->SetContinuousPhysics(true);
 
	// 设置物理碰撞的监听代理
	world->SetContactListener(this);
 
	//地面物体定义
	b2BodyDef groundBodyDef;
	// 左下角
	groundBodyDef.position.Set(winSize.width / 2.0 / PTM_RATIO,winSize.height / 2.0 / PTM_RATIO);
	// 设置为静态物体
	groundBodyDef.type = b2_staticBody;
 
	// 创建地面物体
	groundBody = world->CreateBody(&groundBodyDef);
 
	// 定义一个有边的形状
	b2PolygonShape groundBox;
 
	// 底部
	groundBox.SetAsBox(winSize.width / 2 / PTM_RATIO,b2Vec2(0,-winSize.height / 2 / PTM_RATIO),0);
	//使用夹具固定形状到物体上
	groundBody->CreateFixture(&groundBox,0);
 
	// 顶部
	groundBox.SetAsBox(winSize.width / 2 / PTM_RATIO,winSize.height / 2 / PTM_RATIO),0);
	groundBody->CreateFixture(&groundBox,0);
 
	// 左边
	groundBox.SetAsBox(0,winSize.height / 2 / PTM_RATIO,b2Vec2(-winSize.width / 2 / PTM_RATIO,0),0);
 
	// 右边
	groundBox.SetAsBox(0,b2Vec2(winSize.width / 2 / PTM_RATIO,0);
}
 
void HelloWorld::addNewSpriteAtPosition(CCPoint &pt)
{
	CCLOG("Add sprite x:%0.2f y:%02.f",pt.x,pt.y);
 
	//创建物理引擎精灵对象
	CCSprite *sprite = CCSprite::create("BoxA.png");
	sprite->setPosition(pt);
	this->addChild(sprite);
 
	float sprWidth = sprite->getContentSize().width;
	float spriHeight = sprite->getContentSize().height;
 
	//物体定义
	b2BodyDef bodyDef;
	bodyDef.type = b2_dynamicBody;
	bodyDef.position.Set(pt.x / PTM_RATIO,pt.y / PTM_RATIO);
	bodyDef.userData = sprite;
 
	b2Body *body = world->CreateBody(&bodyDef);
 
	// 定义2米见方的盒子形状
	b2PolygonShape dynamicBox;
	// 注意这里的宽度和高度都是精灵的一半再除以PTM_RATIO
	dynamicBox.SetAsBox(sprWidth / 2 / PTM_RATIO,spriHeight / 2 / PTM_RATIO);
 
	// 夹具定义
	b2FixtureDef fixtureDef;
	//设置夹具的形状
	fixtureDef.shape = &dynamicBox;
	//设置密度
	fixtureDef.density = 1.0f;
	//设置摩擦系数
	fixtureDef.friction = 0.3f;
	//设置弹力系数
	fixtureDef.restitution = 0.5f;
	//使用夹具固定形状到物体上  
	body->CreateFixture(&fixtureDef);
}
 
void HelloWorld::update(float delta)
{
	world->Step(delta,8,3);
 
	for (b2Body* b = world->GetBodyList(); b; b = b->GetNext())
	{
		if (b->GetType() == b2_dynamicBody)
		{
			if (b->GetUserData() != NULL)
			{
				CCSprite* sprite = (CCSprite*)b->GetUserData();
				sprite->setPosition(ccp(b->GetPosition().x * PTM_RATIO,b->GetPosition().y * PTM_RATIO));
				sprite->setRotation(-1 * CC_RADIANS_TO_DEGREES(b->GetAngle()));
			}
		}
	}
}
 
void HelloWorld::BeginContact(b2Contact* contact)
{
	if (contact->GetFixtureA()->GetBody() == groundBody || contact->GetFixtureB()->GetBody() == groundBody)
	{
		CCLOG("检测到物理碰撞");
	}
}
 
void HelloWorld::onEnter()
{
	CCLOG("HelloWorld::onEnter");
	CCDirector::sharedDirector()->getTouchDispatcher()->addTargetedDelegate(this,-128,false);
	CCLayer::onEnter();
}
 
void HelloWorld::onEnterTransitionDidFinish()
{
	CCLOG("HelloWorld::onEnterTransitionDidFinish");
	CCLayer::onEnterTransitionDidFinish();
}
 
void HelloWorld::onExit()
{
	CCLOG("HelloWorld::onExit");
	CCDirector::sharedDirector()->getTouchDispatcher()->removeDelegate(this);
	CCLayer::onExit();
}
 
bool HelloWorld::ccTouchBegan(CCTouch *pTouch,CCEvent *pEvent)
{
	CCPoint pt = pTouch->getLocation();
	this->addNewSpriteAtPosition(pt);
	return true;
}
 
void HelloWorld::ccTouchEnded(CCTouch *pTouch,CCEvent *pEvent)
{
}
 
void HelloWorld::ccTouchMoved(CCTouch *pTouch,CCEvent *pEvent)
{
}
 
void HelloWorld::ccTouchCancelled(CCTouch *pTouch,CCEvent *pEvent)
{
 
}