Updated EXA docs

[Jesse Barnes]

On Sunday, August 07, 2005 10:16 am, Eric Anholt wrote:
> I would nitpick it a bit:
> "depends on your screen's pitch alignment constraints" ->
> "should use the X value from the adjusted width based on virtualX,
> after accounting for the accelerator's pitch alignment constraints."
>
> In "every access to the framebuffer..." that sounds like it would
> cover CPU accesses to the framebuffer, which doesn't make sense and
> isn't true.  Instead, "Alignment settings for pixmaps, to allow for
> hardware acceleration from and to them.  Not applied to all pixmaps
> -- the visible screen is an exception, and thus Prepare* acceleration
> hooks should test for these and fail appropriately." 
> offscreenByteAlign is the value that the pixmap's offset from
> beginning of framebuffer must be aligned to.  offscreenPitch is the
> value that the pitch of a pixmap must be aligned to (also ALIGN_POT
> applies).
>
> Stride is another name for pitch -- the offset from the beginning of
> one line of the pixmap to the next)
>
> In the xvideo bit about sizing, I would s/must/should/ -- I don't
> think it's required, but I don't know.

Ok, updated.  Thanks again for reviewing.

Jeses