C++版 小球自由落体的实现

/**@*complier:vc++ 2008*Date:8/11/2013*Author:pjgan*//**Param Describe: *m_ballreboundCount: the rebound count*m_ballnextpos: next position;*KBALLDESTINATIONPOS: the bottom of the ground*KBALLINITSPEED: the speed of the ball*m_pAcorn: the object( the ball)*m_ballState: the ball's state*/void CSEGameMainPage::balldrop(VINT32 idestionpos) { // the ball drop    if(m_pAcorn[0]) {        VINT32 iballcurrentYpos = m_pAcorn[0]->GetYpos();        if(iballcurrentYpos > idestionpos) {             m_ballreboundCount++; //the rebount count            VDOUBLE dreboundCountDistance = Global_pow(0.5, m_ballreboundCount);            m_ballnextpos = KBALLDESTINATIONPOS - (KBALLDESTINATIONPOS * dreboundCountDistance);//set the rebound position            m_ballState = BALLSTATE_REBOUND; //         } else {            /*            *set the drop speed;            */            m_InitballSpeed  /= KBALLINITSPEED;            m_InitballSpeed  += KBALLINITSPEED*2;            if((m_CurTime - m_LastTime) > 20) {                m_pAcorn[0]->SetYpos(iballcurrentYpos + m_InitballSpeed);                m_LastTime = m_CurTime;            }        }    }}void CSEGameMainPage::ballrebound(VINT32 idestionpos) { // the ball rebound    if(m_pAcorn[0]) {        VINT32 iballcurrentYpos = m_pAcorn[0]->GetYpos();        if(iballcurrentYpos <= idestionpos) {            m_ballnextpos = KBALLDESTINATIONPOS;            m_ballState = BALLSTATE_DROP;        } else {            /*            *set the rebound speed             */            m_InitballSpeed  /= KBALLINITSPEED;            m_InitballSpeed  += KBALLINITSPEED*2;            if((m_CurTime - m_LastTime) > 20) {                m_pAcorn[0]->SetYpos(iballcurrentYpos - m_InitballSpeed);                m_LastTime = m_CurTime;            }        }    }}    switch(m_ballState) {        case BALLSTATE_INITSTATE:            SquirrelsRun();            break;        case BALLSTATE_DROP:            balldrop(m_ballnextpos);            break;        case BALLSTATE_REBOUND:            if(m_ballnextpos < KBALLDESTINATIONPOS) {                ballrebound(m_ballnextpos);            } else {                m_ballState = BALLSTATE_STOP;            }            break;        case BALLSTATE_STOP:            break;        default:            GEASSERT(0);            break;    }