Question

我有一个游戏从左边的玩家右侧射击坏人。

随着游戏时间的增加，我希望我的敌人的生成率变得更快。

我在初始版和初版中设置了一个双timeOfStart = CACurrentMediaTime();。更新方法中的NSLog(@"time is %d", timeOfStart + dt);。

但我得到的价值如下：

time is 1581741008
time is 863073232
time is -1024003120
time is -1390701616
time is 14971856

为什么我会得到大值，然后更小，然后是负值！？

Answer 1

CACurrentMediaTime（）返回double值。

所以

NSLog(@"time is %f", timeOfStart + dt);

您可以通过两种方式跟踪时间：

使用NSTimeInterval

//Declare it as member variable in .h file
NSTimeInterval      mLastSpeedUpdateTime;


//In .m init method
mLastSpeedUpdateTime = [NSDate timeIntervalSinceReferenceDate];

//In update method
NSTimeInterval interval = [NSDate timeIntervalSinceReferenceDate];

float diff = (interval - mLastSpeedUpdateTime);

if(  diff > 5.0f ) //5second
{
     //here update game speed.
     mLastSpeedUpdateTime = [NSDate timeIntervalSinceReferenceDate];
}

手动追踪时间：

   //Declare this in .h
   float                mTimeInSec;

.m init method
mTimeInSec = 0.0f;

   -(void)tick:(ccTime)dt
    {
         mTimeInSec +=0.1f;

          //update gamespeed for every 10sec or on ur needs
          if(mTimeInSec>=10.0f)
          {
            //update game speed
            mTimeInSec = 0.0f;
          }  
    }

如何在cocos2d中跟踪时间

1 个答案: