/*
让cpu画正弦函数:
把一条正弦曲线的弧度划分为200等分进行抽样,计算每个抽样点的振幅
然后每隔300ms的时间取下一个抽样点,让cpu工作对应振幅的时间
*/
#include "windows.h"
#include "stdlib.h"
#include "math.h"
const int SAMPLING_COUNT =200; //抽样点的时间
const double PI = 3.1415926535; //pi值
const int TOTAL_AMPLITUDE = 300; //每个抽样点对应的时间片
int main()
{
DWORD busySpan[SAMPLING_COUNT];
int amplitude = TOTAL_AMPLITUDE/2;
double radian = 0.0;
double radianIncrement = 2.0/(double)SAMPLING_COUNT; //抽样幅度的增量
//对其进行划分
for(int i = 0; i<SAMPLING_COUNT;i++)
{
busySpan[i]=(DWORD)(amplitude+(sin(PI * radian ) * amplitude));
radian += radianIncrement;
}
//让cpu工作对应的时间片
DWORD startTime = 0;
for(int j = 0; ; j = (j+1) % SAMPLING_COUNT)
{
startTime = GetTickCount();
while ((GetTickCount() - startTime) <= busySpan[j] )
{
;
}
Sleep(TOTAL_AMPLITUDE - busySpan[j]);
}
return 0;
}
参考书籍:《编程之美》----微软技术面试心得