Re: SVGCards?

[Callum McKenzie <callum physics otago ac nz>]

On Wed, 2005-09-07 at 18:18 +0000, Nelson Ben�z wrote:
> If you read planet gnome then you probably already know it :), but 
> Federico posted an interesting entry[1] on how vertical tiles are much 
> more efficient that horizontal ones (horizontal tiles are heavily used 
> in gnome-games). Maybe this could be a minor todo for gnome-games.
> 
> [1] http://primates.ximian.com/~federico/news-2005-08.html#05

As Richard has pointed out it probably isn't an optimisation these days,
but I thought I'd better write down exactly why (or at least what I
thought back when Federico made his post).

It makes no difference for reading the data in because a) We deal with
it all in one go, and b) we scale it using bilinear filters and the like
which loose locality of reference since they look at surrounding pixels.
So changing the file formats won't change anything.

Once the data is in the X servers memory then the optimisation is
potentially useful. Usually we will be using hardware acceleration for
the bitblt process, in which case it doesn't really matter. That leaves
unaccelerated X servers, where I suspect it might be useful, but it
depends *very* much on the memory subsystem as to how useful it is.

One day I will get some hard numbers. But it is definitely a long-term
thing.

 - Callum