问题
When using DirectInput, it is my understanding that the mouse wheel delta should be stored in DIMOUSESTATE objects lZ variable. However, when I am scrolling with my laptop touchpad instead of an actual mouse with a wheel, it seems like the scroll is not being recognized since 1Z remains zero always. Is there a better solution than using WM_MOUSEWHEEL if that will even work? Since I am currently using DirectInput for the rest of the input I would like to stay consistent and use that but how can I get the scroll information from the touchpad?
Thanks!
来源：https://stackoverflow.com/questions/9186792/c-directinput-mouse-scroll-wheel-with-a-laptop-touchpad