On Mon, 10 Mar 2003, Holden Hao wrote:
..
> What is a frame buffer device?

it's a virtualization of your video card.
your video card appears to be an area of memory.

so by writing to that memory (e.g. you can define a pointer to point to 
the address, so simply by using indirection) you can draw graphics in a 
sort-of system-independent way, without using X.

if you remember the old CGA graphics card, di ba 0xb800:0000 yung address 
nun? and if you write data into that area, it will show up on-screen?

that's how the frame-buffer works. of course the address is DYNAMIC -- it 
is determined by the Linux kernel (there is a function call which will 
return the frame-buffer address).


> What is its use?

for really lightweight, platform-independent graphics. the disadvantages 
are..

1) no (or little..) hardware 2D acceleration
2) no 3D hardware acceleration

or.. a quick answer.. it lets you have a neat graphical Tux in the 
upper-left corner of the screen when your kernel is booting  :)


---
Orlando Andico <[EMAIL PROTECTED]>
Mosaic Communications, Inc.

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