Using XACT for sound

[sorcerak]

Xact seems relatively new and information seems hard to find about it.

I am interested to know if anyone has found any good sources of information on how to do 3D sound with this?

[lp rob1]

This really should be XAudio2, not XACT. XACT is XAudio Creation Tool, which allows you to mix channels and produce a workable .wav file at the end. So...

Using XAudio2 for sound

But, more to the point, is there any info available on XAudio2? As sorcerak said (abit a year ago) tutorials are very hard to find.

[Hieran_Del8]

Actually, XACT is an appropriate api. It's a loose wrapper for XAudio. I still don't know of any good tutorials on either XACT3 or XAudio2 apis, except for those put out by microsoft. It's funny, doing a google search for "XACT3 tutorial", I ran across my own post asking for tutorials at: http://www.d3dcoder.net/phpBB/viewtopic.php?f=5&t=36.

I forgot about that post, again.

[lp rob1]

I was just reading some reviews about XACT (XAudio2) and OpenAL and found this:

According to Microsoft, XAudio2 is intended to replace DirectSound, and offers programmable DSP effects, full surround sound and 3D spatialisation. However, Creative still argues that ‘OpenAL is a very powerful alternative to Direct X, and is the audio engine of choice for most leading game developers, with new titles being released all the time.’

The main reason for this is because OpenAL supports hardware acceleration, which XAudio 2 apparently doesn’t. This, according to Creative, allows ‘much faster and higher quality sample rate conversion, 3D spatialisation, environmental reverb, filtering and other DSP effects.’

To see the full article, see http://www.bit-tech.net/custompc/news/601200/creative-disses-microsoft-xaudio2.html

So OpenAL supports hardware acceleration, where as XACT doesn't. Does that mean that OpenAL is better that XACT? Also, because XACT is designed by Microsoft, does that mean that XAudio2 will not work on Linux and other Unix systems? There is woefully little information on the net about XAudio2's status in the Linux world.

[Lonewolff]

Yes, Xaudio is Windows only (XP SP2 and above - if I remember correctly). So, if you were looking for cross platform OpenAL would probably be the way to go.

[lp rob1]

But which API has cleaner syntax, quicker functions, better quality?

[lp rob1]

More info:
Some sites say that the hardware acceleration in OpenAL doesn't always work, it has less updates etc. Also, many people who have used OpenAL then looked at XACT find XACT cleaner to use.

[lp rob1]

Well? Anyone? Which is better? Does hardware acceleration ACTUALLY do something? Also, what hardware would be used for acceleration? Sound card?

[Hieran_Del8]

I'm satisfied when basic effects are applied to sound (Doppler shift, environmental reverb, sound occlusion, etc.). The hardware accelerated sound would obviously be faster for short sounds, ie. gun shot. They can be loaded into sound memory (creative's x-ram) ahead of time, much like loading managed resources into a graphics card. An introductory set of tutorials to OpenAL is available at: http://www.devmaster.net/articles.php?catID=6. Altogether, the api looks about as clean as OpenGL.

The nice thing about XACT is that it is constantly being updated, it has a nice audio creation tool gui, and it compiles audio for the xbox and windows. I like XACT/XAudio, as their interfaces are similar in design to DirectX. I don't enjoy OpenGL's or SDL's api as much, and OpenAL is similar in design to that.

So which is better? It's a matter of preference, in my opinion.

[lp rob1]

The hardware accelerated sound would obviously be faster for short sounds, ie. gun shot. They can be loaded into sound memory (creative's x-ram) ahead of time, much like loading managed resources into a graphics card.

So hardware acceleration only works with a sound card. One thing that I have always wondered is how game developers use sound card memory like Creative's X-Ram. But XACT cannot use sound card memory? Only OpenAL?

Altogether, the api looks about as clean as OpenGL.

I have never tried to program in OpenGL. One thing that bugs me about it is that you have to go out and research OpenGL parts, because there is no one SDK which I can download and use like with DirectX. But I suppose this won't apply to OpenAL.

Summary:

• OpenAL can ultilise sound card memory, XACT can't
• OpenAL works for both Windows and Linux
• XACT has a neat audio editing tool allowing you to put all your sounds into one file (wave bank)
• XACT can make audio for the Xbox aswell as Windows
• You don't like OpenGL's API, which is closely related to OpenAL's

Please correct me if I am wrong about something here.