HID filter driver confusion

Hi,

I was looking into making a mouse acceleration driver and came across this page, which explicitly lists this as a use case for a lower-level class filter driver. I looked further and found this page where MOUCLASS.sys is listed, which seems like an exact match for this use case, however the page also mentions that only an upper-level filter driver may be used in combination with MOUCLASS.sys. To a newbie like me this seems like a direct contradiction. So what’s the truth here?

Thanks.

Wouldn’t it be easier and cheaper to buy a mouse that already supports acceleration curves? :wink:

The document mentions being an upper filter to mouhid.sys. That is exactly the same as being a lower filter to mouclass.sys.