UnConeD

26th March 2002 01:47 UTC

AVS uses hardware overlays to achieve this effect (based on the principle of color keying)... it's really not that hard, I bet there's a few tutorials on the web that teach you how to use them. AVS is not the only plug-in to support this by the way... I think Albedo was first. Also, check out 'Drempels'... it's a nice program that acts as an animated desktop background (not reponsive to music though).

ryan

26th March 2002 21:40 UTC

To add one more thing to what UnConed said you can get Milkdrop also from Ryan Geiss at his site witch runs in Overlay mode and it does respond to music. Get it all at Geisswerks.com.


Later

UnConeD

27th March 2002 01:16 UTC

Just to clarify, Drempels is also by Ryan Geiss. Drempels is actually cool if you're looking for something animated that's not hyper-active. Plug-ins such as Milkdrop or AVS are too flashy to run as desktop background IMO :).

ryan

27th March 2002 02:09 UTC

Drempels is da shiznit =)

ciber-fred

17th April 2002 15:12 UTC

is there any sample code to do this, i don't understand how to do this outside a window.

i think the technique is :

take the backgound in a surface
then take this color key to black (for example)
draw something in another surface

and flip the drawing surface before the first (with color key)..

is it ?

but with directX how to draw on the desktop ?

UnConeD

17th April 2002 16:56 UTC

I don't know, but looking up 'hardware overlays' in the DX docs should end up somewhere. I remember that the DX5.2 SDK had an overlay demo called 'donuts'. That might be a starter too.

ciber-fred

18th April 2002 10:03 UTC

so ok it use overlay but overlay draw directly on the screen and not on desktop wallpaper.. i'm looking for some code but it's incredible. no source code to do this. No explanation... grrrr i feel like crazy !

goebish

18th April 2002 14:35 UTC

hardware overlay
I think overlay is a feature you can found since DX 7...Look for DirectX 7 SDK documentation and you should find what you're looking for...

ciber-fred

22nd April 2002 09:01 UTC

ok i found how to do this... but it's a direct draw features. In directX8 directdraw don't exist anymore... (snif!) anybody find how to use overlay with directX8 ?

goebish

22nd April 2002 14:03 UTC

????
DirectDraw don't exist anymore ? But then how do the games like halflife to run in D3D ?

UnConeD

23rd April 2002 01:49 UTC

DirectDraw doesn't exist anymore and has been merged with Direct3D ('DirectX Graphics'). Older programs (DX7 and below) can still call and use DirectDraw, but any program that wants to use DX8 features has to convert all its code that uses DirectDraw into Direct3D code.

The switch is not too bad, because DD only did 2D and didn't handle much special effects. D3D can do everything DD does, and can take advantage of the latest hardware features. For example, menu's and health bars (and the like) and now done by making simple rectangular polygons 'float' in front of the camera (with z-buffer checking disabled). This might seem silly at first, but the overhead is almost nothing, so it doesn't affect the speed. Some games already did this by the way.

Not that this should matter to anyone who simply wants to play games, not program them :).