[maemo-developers] Wishlist (was:Re: N800 and USB host mode)

From: Daniel Amelang daniel.amelang at gmail.com
Date: Thu Mar 8 23:06:00 EET 2007
On 3/7/07, Eero Tamminen <eero.tamminen at nokia.com> wrote:
> Err.  Translucency means compositing and keeping the composited items in
> memory.  Due to additional memory accesses needed for this, it would be
> slower (and take more memory) regardless of how "accelerated" it would
> be.

Keeping the composited items in memory is not necessary. After you
composite, you can (and often) just keep the final result around. It
is true that certain applications may cache the intermediate surfaces
to optimize performance, but that's where the hardware acceleration
comes in. If we had it, we might not need to keep those intermediate
surfaces around as much, and thus you would actually use _less_ memory
if you had hardware acceleration.

So, I don't buy that translucency implies increased memory use to the
point that the additional performance from hardware accelerated
graphics is overshadowed.

> You can see this even on Desktop, just ask how many gamers are happy
> with integrated graphics cards which share memory with the rest of the
> system instead of having (hundreds of megs) of their own memory in which
> to store textures etc. and in where the operations can be done without
> loading the memory bus of the rest of the system (downside is that all
> this costs, adds to the computer power consumption & heating).  :-)

I don't totally agree here either. It sounds like you're saying that
the hardware acceleration won't get you much unless you have dedicated
video memory.

Here's a counter-example: the macbook uses an integrated graphics card
to do all of its fancy accelerated UI effects, including translucency.
Yes, the macbook is not a gaming machine, but that's not the issue,
here. The issue is that hardware-accelerated graphics enable advanced
user interfaces, even w/out dedicated video memory.

Dan

More information about the maemo-developers mailing list