i submitted the windows mousewheel code, to make it work
like linux awhile back. it is working well enough, but
one of my users did discover a problem. i looked it up
and it is definitely a bug for us in SDL.
windows sends the WM_MOUSEWHEEL position in "screen-space"
coordinates. (a nice opposite of all other mouse messages
which are in “client-space”)
anyways, we need to change the code so the reported mouse
coordinates are correct. likely something with GetClientRect
to subtract out the difference?