Heres something I created long long ago when VGA cards where becoming popular.
Whats so interesting about this old 16 bit code is how you can write a pic directly
to the VGAs memory, just once, then move the pic around on the screen without
clearing or re-writing the pic data. This is real smooth panning done at very low
levels using assemblys IN and OUT instructions. How this is achieved is simply by
changing either the X and/or Y start location on the card. I doubt you?ll be able
to play with this neat and fun trick if your running NT, unless you have an old DOS
boot disk laying around. I stuck in a reasonable amount of comments so you should
find it easy to follow. You may note that the prog is less then 5K most of which is
pic and color data.:rolleyes:

Now heres my question, can a similar effect be achieved by Windows? If so, how??
Is OpenGL or DirectX the only way to pan this smoothly in full screen, if at all.:confused:

Low Level Panning example here.
Posted on 2001-08-26 06:38:57 by bcraven
Laptops do this, but I'm sure it's the video driver.
Posted on 2001-08-26 11:43:59 by bitRAKE
Hi bitRAKE,

Back in the old days I had tons of fun exploring the PCs hardware.
Video cards, sound cards, drive controllers and any port I could
discover and play with. Don?t get me wrong, windoz is fun to play
with too, but in a different way.

I would like to pick up more windoz graphics skills. I played with
bitblt in an attempt to create the bouncing effect as in the low level
example but didn?t care for the result.:o
Posted on 2001-08-27 06:27:57 by bcraven
Yeah, I know what you mean. I also know my video card has a lot power that is being unused by windows - scrolling being one of them. Those features are exposed in directX, but I doubt they are under GDI, and certainly wouldn't be 'standard' if they were. Hopefully M$ has fixed this with GDI+, but I doubt it.

I'd like to have a smart lock-scroller program. It would lock on to window borders if the windows were large enough, but would otherwise allow me to scroll around freely. It would take a while to get the 'feel' right, but I think it would be a cool feature. I could have several windows open and quickly scroll between them. It'd be different. :)
Posted on 2001-08-27 08:45:35 by bitRAKE