Efficient Blitting

hi,

I have a problem regarding efficiently displaying two
surfaces with continuous updates in both of them.

Here is the complete scenerio, I have two
SDL_Surface’s, First 'BGND’is the rapidly updating
background and the second 'LINES’one is the color
keyed layer over BGND with fast moving lines .

When I blit:

LINES blits on BGND => BGND with combined effect.

what I want is

LINES blits on BGND => a new surface which should be
directly copied to framebuffer without modifying the
BGND.

I can do that in software but it will be very slow
(creating a third surface and doing 2 blits each
time). How can i do that in hardware? or any other
tip.

I need to solve this problem ASAP. so please help.

waiting…

Regards,
Arslan__________________________________________________
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