游戏笔记，敌人朝向玩家和跟踪代码

//敌人面朝玩家
CGPoint diff = ccpSub(player.position,enemy.position);
    float angleRadians = atanf((float)diff.y / (float)diff.x);
    float angleDegrees = CC_RADIANS_TO_DEGREES(angleRadians);
    float cocosAngle =-1* angleDegrees;
    if (diff.x <0) {
        cocosAngle +=180;
    }
enemy.rotation = cocosAngle;
//跟踪移动
    id actionMove = [CCMoveBy
actionWithDuration:actualDuration position:ccpMult(ccpNormalize(ccpSub(_player.position,
enemy.position)), 10)];