Your on the right track, texture coordinates work on a 0.00-1.00 style scale, so if you set the UV coordinates to 0.0,0.0,0.5,0.5 - you'd get the top left quarter of the image. I can't really make a code snippet for you right now, but I know for sure that it works because I use the same method in my matrix editor for UV mapping the tiles - you select the texture area the selection is shown in a scaled up sprite. All you really need to do is calculate the size of your physical screen in comparison to your background, then that can be your size, and scrolling is a case of changing the start X and Y of the UV. You'd have something like (psuedo code):
Scrollx#=0
Scrolly#=0
Widthx#=screen width()/imagewidth
Widthy#=screen Height()/imageheight
sprite 1,1,0,0
set sprite size 1,0,0,screen width(),screen height()
do
inc scrollx#,mousemovex()/1000.00
inc scrolly#,mousemovey()/1000.00
if scrollx#<0.0 then scrollx#=1.0-widthx#
if scrollx#>(1.0-widthx#) then scrollx#=0.0
if scrolly#<0.0 then scrolly#=1.0-widthy#
if scrolly#>(1.0-widthy#) then scrolly#=0.0
set sprite texture coord 1,scrollx#,scrolly#,scrollx#+widthx#,scrolly#+heighty#
sync
loop
If your still struggling by the weekend, I'll have my PC back and can make a proper example.
Van-B
My cats breath smells of cat food.
