cocos2dx实现环形角色选择界面

数据结构采用双向循环链表。由候选角色组成链表的节点，将链表中的节点在屏幕上按照椭圆分布。

 .h:

//链表节点——候选角色
class CandidateRole :public CCNode{
public:
    CandidateRole();
    ~CandidateRole();
    virtual bool init(const char* name);
    static CandidateRole* create(const char* name);
    CandidateRole* mpNextRole; //节点右面角色的指针
    CandidateRole* mpForeRole;  //..左..........     

     void setPositionIndex(int );
     int getPositionIndex();   

    int mDistance;     //到椭圆最低点的距离
    int mPositionIndex;     //节点在链表中的序号
    int mNextPositionX;    
    int mNextPositionY;
    int mColorR;
    int mColorG;
    int mColorB;
    CCArmature* mpArmature;
    bool mbIsSelected;   // 是否被选中

};


//由候选角色组成的链表，在屏幕上成椭圆分布
class CircleStage :public CCNode{

public:
    CircleStage();
    ~CircleStage();
    virtual bool init();
    
    CREATE_FUNC(CircleStage);
    void addRole(CandidateRole *);    //添加一个角色到链表
    void changeToNext();    //顺时针旋转
    void changeToFore();    //逆时针旋转
    
    bool isOnAction();
    void actionEnd();

private:
    bool mbOnAction;
    int mRoleNum;
    CandidateRole* mpCurrentRole;     //操作链表用的指针
    CandidateRole* mpHead;
    CandidateRole* mpLast;
    CandidateRole* mpSelectRole;    //被选中的角色，在椭圆最低点
    int mCircleA;    //椭圆的a
    int mCircleB;    //椭圆的b
    void updateColor();    //更新每个节点的明暗，越远越暗
    void updateZorders();    //更新遮盖关系
        void updateZordersCallBack();
    void updateDistances();    //更新每个节点到中央节点的距离
    void initAppearance();    //初始化颜色和缩放
    
};        

.cpp:

CandidateRole::CandidateRole()
{

}
CandidateRole::~CandidateRole()
{

}
bool CandidateRole::init(const char* name)
{

    mPositionIndex=0;
    mbIsSelected=false;
    mDistance=0;
    mColorB=255;
    mColorG=255;
    mColorR=255;
    
    mpArmature = CCArmature::create(name);
    this->addChild(mpArmature);

    return true;
}

CandidateRole* CandidateRole::create(const char* name)
{
    CandidateRole* pRet = new CandidateRole();
    if (pRet && pRet->init(name))
    {
        pRet->autorelease();
    }
    else
    {
        CC_SAFE_DELETE(pRet);
    }
    return pRet;
}

void CandidateRole::setPositionIndex(int index)
{
    mPositionIndex=index;
}

int CandidateRole::getPositionIndex()
{
    return mPositionIndex;

}

CircleStage::CircleStage()
{

}

CircleStage::~CircleStage()
{

}

bool CircleStage::init()
{

    mCircleA=ScreenWidth*0.4;
    mCircleB=80;
    mRoleNum=0;
    mpHead=NULL;
    mbOnAction=false;
    for(int i=0;i<8;i++)
    {
        CandidateRole* role=CandidateRole::create("role");
        this->addRole(role);

    }
    updateDistances();
    updateZorders();
    initAppearance();
    return true;

}
void CircleStage::updateColor()
{
    mpCurrentRole=mpSelectRole;
    for (int i=0;i<mRoleNum;i++)
    {
        mpCurrentRole->mColorR=255;
        mpCurrentRole->mColorG=255;
        mpCurrentRole->mColorB=255;
        for (int j=0;j<mpCurrentRole->mDistance;j++)
        {
            
            mpCurrentRole->mColorR*=0.6;
            mpCurrentRole->mColorG*=0.6;
            mpCurrentRole->mColorB*=0.6;
        }
        mpCurrentRole->mpArmature->setColor(ccc3(mpCurrentRole->mColorR,mpCurrentRole->mColorG,mpCurrentRole->mColorB));
        mpCurrentRole=mpCurrentRole->mpNextRole;
    }
}

void CircleStage::updateDistances()
{
    mpCurrentRole=mpSelectRole;
    int distance=0;
    for (int i=0;i<=mRoleNum/2;i++)
    {
    mpCurrentRole->mDistance=distance;
    ++distance;
    mpCurrentRole=mpCurrentRole->mpNextRole;

    }
    mpCurrentRole=mpSelectRole;
    distance=0;
    for (int i=0;i<=mRoleNum/2;i++)
    {
    mpCurrentRole->mDistance=distance;
    ++distance;
    mpCurrentRole=mpCurrentRole->mpForeRole;
    }

    mpSelectRole->mDistance=0;
}
void CircleStage::initAppearance()
{
    mpCurrentRole=mpSelectRole;

    for (int i=0;i<mRoleNum;i++)
    {
        double scale=1;
        
        for (int j=0;j<mpCurrentRole->mDistance;j++)
        {
            scale*=0.8;
            mpCurrentRole->mColorR*=0.6;
            mpCurrentRole->mColorG*=0.6;
            mpCurrentRole->mColorB*=0.6;
        }
        mpCurrentRole->setScale(scale);

        mpCurrentRole->mpArmature->setColor(ccc3(mpCurrentRole->mColorR,mpCurrentRole->mColorG,mpCurrentRole->mColorB));
        mpCurrentRole=mpCurrentRole->mpNextRole;
    }
    mpSelectRole->setScale(1.0f);

}

void CircleStage::updateZorders()
{
    mpSelectRole->setZOrder(mRoleNum);
    mpSelectRole->mDistance=0;
    mpCurrentRole=mpSelectRole;
    
    for (int i=0;i<=mRoleNum/2;i++)
    {

        mpCurrentRole->setZOrder(mRoleNum-mpCurrentRole->mDistance);
        mpCurrentRole=mpCurrentRole->mpNextRole;
    }
    for (int i=mRoleNum/2+1;i<mRoleNum;i++)
    {
        
        mpCurrentRole->setZOrder(abs(mRoleNum/2-mpCurrentRole->mDistance));
        mpCurrentRole=mpCurrentRole->mpNextRole;
    }

}




void CircleStage::addRole(CandidateRole *newRole)
{
    if (!mpHead)
    {
        mpHead=newRole;
        this->addChild(newRole);
        mpLast=mpHead;
        mpLast->mpNextRole=mpHead;
        mpHead->mpForeRole=mpHead;
        mpCurrentRole=mpHead;
        mRoleNum++;
        mpCurrentRole->setPositionIndex(mRoleNum);
        mpSelectRole=newRole;
    } 
    else
    {
        mpLast->mpNextRole=newRole;
        newRole->mpNextRole=mpHead;
        newRole->mpForeRole=mpLast;
        mpHead->mpForeRole=newRole;
        this->addChild(newRole);
        mpLast=newRole;
        mRoleNum++;
        newRole->setPositionIndex(mRoleNum);
    }
    int x,y;
    double t;
    while(1)
    {    
        t=360/mRoleNum*(mpCurrentRole->getPositionIndex()-1)-90;
        t=t*3.14/180;//convert t to radian
        x=mCircleA*cos(t);
        y=mCircleB*sin(t);
        mpCurrentRole->setPositionX(x);
        mpCurrentRole->setPositionY(y);
        mpCurrentRole=mpCurrentRole->mpNextRole;

        if (mpCurrentRole==mpHead)
        {
            break;
        }

    }
}

void CircleStage::changeToNext() //从右向左
{
    mpSelectRole=mpSelectRole->mpNextRole;
    CCCallFunc* callFuncActionEnd = CCCallFunc::create(this,callfunc_selector(CircleStage::actionEnd));
    CCCallFunc* callUpdateZorder = CCCallFunc::create(this,callfunc_selector(CircleStage::updateZordersCallBack));
    if (mpCurrentRole->mpNextRole)
    {
        
        mpSelectRole->setZOrder(mRoleNum);
        for (int i=0;i<mRoleNum;i++)
        {
    
            mpCurrentRole->mNextPositionX=mpCurrentRole->mpForeRole->getPositionX();
            mpCurrentRole->mNextPositionY=mpCurrentRole->mpForeRole->getPositionY();
            mbOnAction=true;
            CCMoveTo *moveToNext=CCMoveTo::create(0.4f,ccp(mpCurrentRole->mNextPositionX,mpCurrentRole->mNextPositionY));
            CCScaleTo *scaleToFore=CCScaleTo::create(0.4f,mpCurrentRole->mpForeRole->getScale());
            CCFiniteTimeAction*  spawnAction = CCSpawn::create(moveToNext,scaleToFore,NULL);
        
            CCSequence* actions = CCSequence::create(spawnAction,callUpdateZorder,callFuncActionEnd,NULL);
            mpCurrentRole->runAction(actions);
            
            mpCurrentRole=mpCurrentRole->mpNextRole;
        
        }
        updateDistances();
        updateColor();
    
    }


}

void CircleStage::updateZordersCallBack()
{
  updateZorders();
}
void CircleStage::actionEnd()
{
    mbOnAction=false;

}

void CircleStage::changeToFore() //从左向右
{
    mpSelectRole=mpSelectRole->mpForeRole;
    CCCallFunc* callFuncActionEnd = CCCallFunc::create(this,callfunc_selector(CircleStage::actionEnd));
    
    if (mpCurrentRole->mpForeRole)
    {
        for (int i=0;i<mRoleNum;i++)
        {
            mpCurrentRole->mNextPositionX=mpCurrentRole->mpNextRole->getPositionX();
            mpCurrentRole->mNextPositionY=mpCurrentRole->mpNextRole->getPositionY();
            mbOnAction=true;
        
            CCMoveTo *moveToFore=CCMoveTo::create(0.4f,ccp(mpCurrentRole->mNextPositionX,mpCurrentRole->mNextPositionY));
            CCScaleTo *scaleToFore=CCScaleTo::create(0.4f,mpCurrentRole->mpNextRole->getScale());
            CCFiniteTimeAction*  spawnAction = CCSpawn::create(moveToFore,scaleToFore,NULL);
            CCSequence* actions = CCSequence::create(spawnAction,callFuncActionEnd,NULL);
            mpCurrentRole->runAction(actions);
            mpCurrentRole=mpCurrentRole->mpNextRole;

        }
        updateDistances();
        updateZorders();
        updateColor();
    
    }
}

bool CircleStage::isOnAction()
{
    return mbOnAction;
}