Cocos2d-x简单Box2d代码示例|点击碰撞>HelloWorldScene.cpp<代码演示>

#include "HelloWorldScene.h"

#include "SimpleAudioEngine.h"

#define PTM_RATIO 32

#define GET_WINSIZE CCDirector::sharedDirector()->getWinSize()

enum {

    

 kTagParentNode =1,

};

using namespace cocos2d;

using namespace CocosDenshion;

USING_NS_CC;

//struct fuc and init elements

PhysicsSprite::PhysicsSprite():m_pBody(NULL){

    

}

//setter machine

voidPhysicsSprite::setPhysicsBody(b2Body *body){

   m_pBody = body;

    

}

boolPhysicsSprite::isDirty(){

    return true;

}

//parentNode trasform

CCAffineTransform PhysicsSprite::nodeToParentTransform(){

    b2Vec2 pos =m_pBody->GetPosition();//get Postion By b2body

   float x = pos.x *PTM_RATIO;//x

   float y = pos.x *PTM_RATIO;//y

    //analiys

    if (isIgnoreAnchorPointForPosition()) {

        x+=m_obAnchorPointInPoints.x;

        y+=m_obAnchorPointInPoints.y;

    }

    

    //make matix

   float radians = m_pBody->GetAngle();

   float c = cosf(radians);//正弦

   float s = sinf(radians);//余弦

    

    if (m_obAnchorPointInPoints.equals(CCPointZero)) {

        x += c * - m_obAnchorPointInPoints.x + -s * -m_obAnchorPointInPoints.y;

        y += s * - m_obAnchorPointInPoints.x + c * -m_obAnchorPointInPoints.y;

    }

    

    //Rot,Translate Matrix

   m_sTransform = CCAffineTransformMake(c,s,-s,c,x,y);

    returnm_sTransform;

}

//HelloWorld structFuc

HelloWorld::HelloWorld(){

    setTouchEnabled(true);//abled touch

    setAccelerometerEnabled(true);//able remote

    

    

    CCSize s =GET_WINSIZE;

    //初始化物理系统

    this->initPhysics();

    CCSpriteBatchNode *parent =CCSpriteBatchNode::create("bloks.png",100);

   m_pSpriteTexture = parent->getTexture();

    addChild(parent,kTagParentNode);

    //position

    addNewSpriteAtPosition(ccp(s.width/2,s.height/2));

    

    CCLabelTTF *label =CCLabelTTF::create("Tap Screen","Marker Felt", 32);

   addChild(label,0);

    label->setColor(ccc3(0,0, 255));

    label->setPosition(ccp(s.width/2, s.height/2-50));

    scheduleUpdate();

}

//析构

HelloWorld::~HelloWorld(){

   delete world;

   world = NULL;

    

//    delete m_debugDraw;

    

}

voidHelloWorld::initPhysics(){

    CCSize s =GET_WINSIZE;

   b2Vec2 gravity;

    gravity.Set(0.0f, -10.0f);

   world = newb2World(gravity);

    

    //DO we want to let bodies sleep:

    world->SetAllowSleeping(true);

    world->SetContinuousPhysics(true);

    

    //m_debugDrae = new GLESDEbugDraw(PTM_RATIO);

//    world->SetDebugDraw(m_debugDraw);

   uint32 flags = 0;

    flags +=b2Draw::e_shapeBit;

//    flags += b2Draw::e_jointBit;

//    flags += b2Draw::e_pairBit;

//    flags += b2Draw::e_centerOfMassBit;

//    flags += b2Draw::e_aabbBit;

    

    //define the ground body

   b2BodyDef groundBodyDef;

    groundBodyDef.position.Set(0,0);//bottom-left center

    

    //call the body factory which allocates memory for the gound body

    //from a pool and created the ground box shape(from a pool)

    //the body is also added to the world

   b2Body *groundBody = world->CreateBody(&groundBodyDef);

    //Define the ground box shape

   b2EdgeShape groundBox;

    //bottom

    groundBox.Set(b2Vec2(0,0), b2Vec2(s.width/PTM_RATIO,0));

    groundBody->CreateFixture(&groundBox,0);

    //top

    groundBox.Set(b2Vec2(0,s.height/PTM_RATIO),b2Vec2(s.width/PTM_RATIO,s.height/PTM_RATIO));

    groundBody->CreateFixture(&groundBox,0);

    //left

    groundBox.Set(b2Vec2(0, s.height/PTM_RATIO),b2Vec2(0,0));

    groundBody->CreateFixture(&groundBox,0);

    //right

    groundBox.Set(b2Vec2(s.width/PTM_RATIO,s.height/PTM_RATIO),b2Vec2(s.width/PTM_RATIO,0));

    groundBody->CreateFixture(&groundBox,0);

}

voidHelloWorld::draw(){

    //Important;

    //This is only for debug purposes

    //It is recommend to disable it

    //本方法用于调试Box2d

   CCLayer::draw();

    ccGLEnableVertexAttribs(kCCVertexAttribFlag_Position);

    kmGLPushMatrix();

    world->DrawDebugData();

    kmGLPopMatrix();

    

}

voidHelloWorld::addNewSpriteAtPosition(CCPoint point){

    CCLog("Add sprite %0.2f x %0.2f",point.x,point.y);

    CCNode *parent =getChildByTag(kTagParentNode);

    //This is just randomly picking one of the images

   int idx = (CCRANDOM_0_1()>.5 ? 0 : 1);

   int idy = (CCRANDOM_0_1()>.5 ? 0 : 1);

    PhysicsSprite *sprite =new PhysicsSprite();

    sprite->initWithTexture(m_pSpriteTexture,CCRectMake(32 * idx, 32 *idy, 32,32));

    sprite->autorelease();

    parent->addChild(sprite);

    

    //Define the dynamic body

    //Set up 1m squared box in the physics world

   b2BodyDef bodyDef;

    bodyDef.type =b2_dynamicBody;

    bodyDef.position.Set(point.x/PTM_RATIO,point.y/PTM_RATIO);

    

   b2Body *body = world->CreateBody(&bodyDef);

    //Define another box shape for our dynamic body

   b2PolygonShape dynamicBox;

    //This is the middle points for our 1m box

    dynamicBox.SetAsBox(0.5f,.5f);

    //Define the dynamic body fixture

   b2FixtureDef fixtureDef;

    fixtureDef.shape = &dynamicBox;//体积

    fixtureDef.density =1.0f;//密度

    fixtureDef.friction =0.3f;

    body->CreateFixture(&fixtureDef);

    sprite->setPhysicsBody(body);

}

voidHelloWorld::update(float dt){

    //It is recommended that a fixed time step is used with Box2D for stabliity

    //of the simulation,however,we are using a variable time step here

    //You need to make an informed choice, the follow URL is useful

    //http://gafferongames.com/game-physics/fix-your-timestep/

   int velocityIterations = 8;

   int positionIterations = 1;

    //Instruct the world to perform a single step of simulation .It is

    //generally best to keep the time step ad iterations fixed;

   world->Step(dt, velocityIterations,positionIterations);

    

    //Iterations over the bodies in the Physics world

   for (b2Body *b =world->GetBodyList(); b; b = b->GetNext()) {

       if (b->GetUserData() !=NULL) {

           CCSprite *myActor = (CCSprite *)b->GetUserData();

            myActor->setPosition(CCPointMake(b->GetPosition().x * PTM_RATIO,

                                             b->GetPosition().y *PTM_RATIO));

            myActor->setRotation(-1*CC_RADIANS_TO_DEGREES(b->GetAngle()));

        }

    }

}

voidHelloWorld::ccTouchesEnded(CCSet *touches,CCEvent *event){

    //Add a new body /atlas sprite at the touched location

    CCSetIterator it;

   CCTouch *touch;

   for (it = touches->begin(); it!= touches->end(); it++) {

        touch = (CCTouch *)(* it);

       if (!touch) {

           break;

        }

       CCPoint location = touch->getLocationInView();

        location =CCDirector::sharedDirector()->convertToGL(location);

        addNewSpriteAtPosition(location);

    }

}

CCScene* HelloWorld::scene(){

   CCScene *scene = CCScene::create();

   CCLayer *layer = newHelloWorld();

    scene->addChild(layer);

    layer->release();

   return scene;

}