如何检测到鼠标滚轮的滚动速度

Question

WM_MOUSEWHEEL消息只能检测到滚轮滚动的方向,那有没有什么办法能检测到滚动的速度呢?

Answer 1

单位时间的鼠标移动的位移量。v=ds/dt.
ds^2=(x2-x1)^2+(y2-y1)^2.   dt=t2-t1.

Answer 2

BOOL QueryPerformanceCounter(
  LARGE_INTEGER *lpPerformanceCount   // counter value
);BOOL QueryPerformanceFrequency(
  LARGE_INTEGER *lpFrequency   // current frequency
);LARGE_INTEGER t1,t2;
.
.
QueryPerformanceCounter(&t1);
.
.
.
QueryPerformanceCounter(&t2);
QueryPerformanceFrequency(&f);
double dt=(double)((t2-t1)/f);
double vx=(point2.x-point1.x)/dt;  //<---
double vy=(point2.y-point1.y)/dt;  //<---