[geeks] Best Vista story I've seen

Charles Shannon Hendrix shannon at widomaker.com
Tue Feb 20 16:34:15 CST 2007


Tue, 20 Feb 2007 @ 12:48 -0500, Joshua Boyd said:

> On Tue, Feb 20, 2007 at 12:21:41AM -0500, Charles Shannon Hendrix wrote:
> 
> > Yes, it is nice to see OpenAL finally make headway, after so many
> > years.  Linux games used it a lot, especially those from now-defunct Loki
> > Games.  I'm kind of surprised to see Microsoft adopt it.  Anyone have any
> > information on why?
> 
> I don't know that MS is adopting it so much as they are not going out of
> their way to block it.

Maybe.  

http://www.openal.org/openal_vista.html

Microsoft Vista completely drops the HAL in DirectSound, primarily
because DRM intercepts everything in the Windows APIs for "authorization
and user protection".

That means *zero* hardware acceleration for any audio done with the
Windows sound API. This breaks a ton of games that used Windows hardware
3D sound for two reasons: it requires too much CPU power, and a number
of features are not possible without the underlying hardware support.
EAX was the primary hardware layer for D3D sound.

OpenAL was adopted, I assume, as a way for games to continue to use
accelerated 3D audio without DRM intefering with gameplay.

The reason for this is because Microsoft requires all drivers that
support the Windows API to meet security guidelines. These include
even such low level things as preventing code from copying data from a
texture in GPU memory, to prevent image "theft", and copying sound
samples from audio hardware.

Irony:

As far as I know, the OpenAL and OpenGL pipelines completely bypass
Vista DRM. I don't know that for sure, but it seems to be true.

If so, how long will it be before we start seeing OpenGL and OpenAL
video and audio players?

It also seems like this could drive game companies to reconsider OpenGL
as their graphics engine.  If you use "authorized" DirectX 3D drivers,
you pay a performance hit that can be quite high.

If you write OpenGL code, it will run full speed and probably more
reliabily.

You guys, if you can stomach it, should read the restrictions Microsoft
imposes on 3D video drivers in order to get full certification.

It's a wonder the stuff will run at all.

I hope Apple isn't going to do any of this.

> > Also, Microsoft's heavy DRM and authentication system relies on control of
> > the entire API including sound... so how can they support cross-platform
> > OpenAL?
> 
> Well, if a game company chooses to use OpenAL, they can't very well
> complain to MS if sounds from the game are ripped via OpenAL.  

You appear to misunderstand me:

I mean that since OpenAL (and OpenGL) don't appear to be part of the DRM
in Vista, intellectual property companies can't protect their content
if people write OpenAL/OpenGL audio and video players.

Microsoft is promising the IP industry that Vista protects this stuff.

> I used to play some games on a PC with one of the earlier
> soundblasters to support EAX.  I don't know how much benefit I got
> from it as I wasn't using surround.  Perhaps unrelated, but the system
> would use the sound card to decode AC3, DTS, etc (when using the
> Creative Labs DVD playing software along with a DXR3 card).  That part
> was cool.  Until lightning took it out the drive (and the replacement
> refused to play nice), I had a Pentium 200mmx as a dedicated DVD
> player w/ surround sound processing attached to the family TV. 

My best examples, because they are fresh in my mind:

F.E.A.R. using EAX 4 the sound is far better, and you get significantly
better frame rates. The sound processor takes a lot of load off the CPU
and the PCI bus. 

"Rome: Total War" and "Medieval 2: Total War", same thing. Both suffer
framerate loss if you use software sound.

The original Live! sound card didn't have much power.  Audigy boosted
the power and Audigy boosted it just a bit more.

In some cases, hardware sound with EAX 1 would make games slower,
because it couldn't offload much of the work.

Starting with Audigy, it got a lot better, and started improving frame
rates.

X-Fi is much more serious hardware with a far faster sound processor.
The top card has a 400MHz DSP with passive cooling, and I think it is a
20 million transistor part. The big advantage of X-Fi is it does 0-96KHz
processing, without requiring down and up sampling like most other
non-professional cards.

For example, even the Audigy 4 does all its processing at 48-bits and
48KHz, which means if you process 96KHz samples, they get downsampled.
You can't even disable that if you want to.

It's not really a big deal unless you reprocess sounds enough to start
causing distortion.

> > It would help remove the hammer lock Creative has on game sound, and give
> > other sound card makers a more level and open playing field, and give game
> > companies one less excuse for not writing portable software.
> 
> Creative is one of the major sponsors of OpenAL.  Aureal was one of the
> other big names, but I don't know if they are still around.  Nvidia
> sponsers OpenAL, but I don't know to what extent their hardware will
> accelerate it.

I know Creative supports it, but right now everyone is forced to emulate
EAX or use Miles 2D: moving to OpenAL would mean no longer having to
follow Creative.  It would give other companies a chance to make better
sound cards.

Some already do, but they can't get market share because they are unable
to duplicate EAX, mostly due to legal reasons.

With OpenAL as the standard, everyone could make compliant cards without
paying royalties to Creative or being sued by them.


-- 
shannon           | Consulting wouldn't be what it is today without Microsoft 
                  | Windows.
                  |        -- Chris Pinkham



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