OpenAL

-WildCat- · January 2010

<div class="IPBDescription">Will Natural Selection 2 support OpenAL audio output?</div>I use Sennheiser HD 280 Pro headphones for playing games and listening to music at my PC. It's a practical solution and I prefer them to 5.1 speakers because they provide clearer sound and they don't annoy my family members. These days, however, I am frequently disappointed with the audio in PC games. The stereo output that they produce is boring. Simple left-to-right panning is hardly a realistic simulation of how sound waves actually interact with the human head.

I have only been impressed by the audio from a few games and those are almost always games that support OpenAL. The main reason being that I can turn on my Sound Blaster X-Fi's <span style="color:#FFFF00">CMSS-3D</span> function, which delivers excellent 3D headphone surround sound using Head-Related Transfer Functions (HRTF).

If I'm not much mistaken, Natural Selection 2 will use the "<span style="color:#FFFF00">FMOD Music and Sound Effects System</span>". According to <a href="http://connect.creativelabs.com/developer/Gaming/SoundBlasterFMOD.pdf" target="_blank">a document at "Creative Labs: Connect"</a>, FMOD supports OpenAL rendering. Here's a quote from the introduction:

<div class='quotetop'>QUOTE (from "Sound Blaster technologies in FMOD" PDF)</div><div class='quotemain'>FMOD is a popular and powerful cross-platform interactive audio system. In the past, FMOD supported hardware accelerated audio on the PC platform through the DirectSound3D interface. However, under Windows Vista, DirectSound3D hardware support is no longer available. Instead, audio hardware manufacturers such as Creative Labs have adopted OpenAL as a direct interface to hardware features. FMOD has been modified to support OpenAL rendering, this document provides developers with hints and tips to ensure a first-rate experience for gamers playing FMOD titles on OpenAL hardware.</div>
The question is: Will Natural Selection 2 implement this functionality?

OpenAL is designed in such a way that it allows games to find all the OpenAL drivers available on your computer and list them in their "audio options" screen. This is probably the ideal implementation because it allows the user to easily select the best driver. If I understand correctly, most users would only see one item in the list - that being "<span style="color:#FFFF00">Generic Software</span>". However, a user such as myself would see more items - In my case: "<span style="color:#FFFF00">Generic Software</span>", "<span style="color:#FFFF00">SB X-Fi Audio [EC00]</span>", and "<span style="color:#FFFF00">Rapture3D</span>".

In case you're interested, <a href="http://blueripplesound.com/index.php?target=products" target="_blank">Rapture3D</a> is a software OpenAL driver created by <a href="http://blueripplesound.com/" target="_blank">Blue Ripple Sound</a>. Like Creative's CMSS-3D, it also produces very immersive 3D headphone surround sound using HRTFs. I found out about it because DiRT2 ships with a special "game" edition of Rapture3D and uses it as its preferred sound device. I bought a copy of the "user" edition, which can be used with some OpenAL games. For a demonstration of 3D headphone surround sound, see the linked Youtube videos at the bottom of this post.

Natural Selection 2 seems like the perfect game to use proper 3D audio. The sounds of clanging footsteps on metal floors ... the sound of an alien's schreak going past your head as you narrowly avoid its pounce ... these things deserve to be heard in surround sound, even by headphone users. The technology is there. It's just a matter of making sure it's implemented fully.

I've already pre-ordered my copy of Natural Selection 2. Can I look forward to 3D headphone surround sound?

<u><b>Links:</b></u>
<ul><li><a href="http://connect.creativelabs.com/developer/Gaming/SoundBlasterFMOD.pdf" target="_blank"><b>Sound Blaster technologies in FMOD</b></a> <span style="font-size:8pt;line-height:100%">(A programmerâ€™s guide to accessing Sound Blaster hardware acceleration via the FMOD music and sound effects system)</span></li><li><a href="http://en.wikipedia.org/wiki/Head-related_transfer_function" target="_blank">Wikipedia - Head-Related Transfer Function (HRTF)</a></li><li><a href="http://en.wikipedia.org/wiki/Sound_Blaster_X-Fi#CMSS-3DHeadphone" target="_blank">Wikipedia - Sound Blaster X-Fi - CMSS-3DHeadphone</a></li><li><a href="http://blueripplesound.com/" target="_blank">Blue Ripple Sound</a>
<ul><li><a href="http://blueripplesound.com/index.php?target=technology" target="_blank">Technology</a></li><li><a href="http://blueripplesound.com/index.php?target=developers" target="_blank">Developers</a></li></ul></li><li><a href="http://www.youtube.com/watch?v=lqqiIR017SQ" target="_blank">Youtube - Rapture3D Audio Demonstration in UT3</a></li><li><a href="http://www.youtube.com/watch?v=iikd_hucZbY" target="_blank">Youtube - Rapture3D Audio Demonstration</a></li></ul>

schkorpio · January 2010

I always thought that you should turn OFF CMSS-3D if the game supports proper sound positioning - such as openAL or EAX4 EAX5

CMSS-3D turns stereo and headphones into a virtual 5.1/7.1 system

Unfortunetly not many people appreciate a games sound as much as the graphics, which is a shame as I really find games with great sound a lot more immersive, so I hope there will be at least EAX4 support which even motherboard built in audio cards support these days

-WildCat- · January 2010

<div class='quotetop'>QUOTE (schkorpio @ Jan 5 2010, 10:09 PM) <a href="index.php?act=findpost&pid=1745805"><{POST_SNAPBACK}></a></div><div class='quotemain'>I always thought that you should turn OFF CMSS-3D if the game supports proper sound positioning - such as openAL or EAX4 EAX5

CMSS-3D turns stereo and headphones into a virtual 5.1/7.1 system</div>
CMSS-3D is a strange beast. It actually does three totally different things depending on what speaker setup you're using. The three modes are "<span style="color:#FFFF00">CMSS-3DHeadphone</span>", "<span style="color:#FFFF00">CMSS-3DVirtual</span>", and "<span style="color:#FFFF00">CMSS-3DSurround</span>". Because I use headphones, "<span style="color:#FFFF00">CMSS-3DHeadphone</span>" is the mode that I use. It takes the sound positioning data that it gets from the OpenAL system and uses HRTFs to produce 3D headphone surround sound. Without CMSS-3D, you'd just get flat stereo sound in your headphones.

Check out the Wikipedia article for details: <a href="http://en.wikipedia.org/wiki/Sound_Blaster_X-Fi#CMSS-3D" target="_blank">Wikipedia - Sound Blaster X-Fi - CMSS-3D</a>

<div class='quotetop'>QUOTE (schkorpio @ Jan 5 2010, 10:09 PM) <a href="index.php?act=findpost&pid=1745805"><{POST_SNAPBACK}></a></div><div class='quotemain'>Unfortunetly not many people appreciate a games sound as much as the graphics, which is a shame as I really find games with great sound a lot more immersive, so I hope there will be at least EAX4 support which even motherboard built in audio cards support these days</div>
My understanding is that EAX is just a library of special effects that can be applied to sounds to simulate various types of environments. Examples would be reverb, distortion, occlusion, etc. As far as I know, FMOD does all this sort of stuff in software.

Tgaud · January 2010

I dont understand how you can have spatialisation more than stereo in .... stereo headphone.
I think thoses 3D things are made for the 7.1 headphones (a lot of little separate speakers , each side, on the headphone)
That's the only way to have a real spatialisation.

-WildCat- · January 2010

<div class='quotetop'>QUOTE (Tgaud @ Jan 5 2010, 11:45 PM) <a href="index.php?act=findpost&pid=1745815"><{POST_SNAPBACK}></a></div><div class='quotemain'>I dont understand how you can have spatialisation more than stereo in .... stereo headphone.
I think thoses 3D things are made for the 7.1 headphones (a lot of little separate speakers , each side, on the headphone)
That's the only way to have a real spatialisation.</div>
No-no - "those 3D things" are made specifically for plain stereo headphones.

Humans have only two ears, so you might think that we'd only be able to tell the difference between sounds coming "mostly from the left" and "mostly from the right". However, humans can actually distinguish the difference between sounds coming from above, below, behind, etc. This is a because sound waves are affected by the shape of your head and ears before they reach your ear-drums (known as HRTF). Your brain interprets these differences and enables you to the determine the origin of sounds.

CMSS-3D (as well as various other technologies) use HRTFs to pre-process sound data and simulate the effect that your head and ears would have on the incoming sound waves if you were really in the simulated environment. It basically tricks your brain in to thinking a sound is coming from behind you when it's actually coming from your headphones.

Draco_2k · January 2010

No official word on that, but OpenAL seems to have become the DirectX of sound recently, so chances are... Yeah.

As an audiophile myself, I really appreciate the approach UW took to their sound department. Gunfire in the trailer still sends chills down my spine.

Anthoni · January 2010

OpenAL is good for 3D Apps, but I am using XACT for my 2D game engine.

rsd · January 2010

I hope the devs take note of this thread. Sound is absolutely critical to me. Especially things such as gunfire. If the weapons sound powerful it changes the whole feel of the game.

Mr. Epic · January 2010

<div class='quotetop'>QUOTE (Draco_2k @ Jan 5 2010, 09:07 PM) <a href="index.php?act=findpost&pid=1745840"><{POST_SNAPBACK}></a></div><div class='quotemain'>No official word on that, but OpenAL seems to have become the DirectX of sound recently, so chances are... Yeah.

As an audiophile myself, I really appreciate the approach UW took to their sound department. Gunfire in the trailer still sends chills down my spine.</div>
that is not in game, its post pro. Hopefully they will implement good reverbs to make the game close to the feel.

-WildCat- · January 2010

<div class='quotetop'>QUOTE (rsd @ Jan 7 2010, 07:45 AM) <a href="index.php?act=findpost&pid=1746049"><{POST_SNAPBACK}></a></div><div class='quotemain'>I hope the devs take note of this thread. Sound is absolutely critical to me. Especially things such as gunfire. If the weapons sound powerful it changes the whole feel of the game.</div>
Yeah, agreed. Poorly done gunfire sound effects can really detract from a game. If they sound weak or artificial, then the shooting aspects of the game become less entertaining and, if they sound too powerful, then you end up being deceived about how much damage you're doing to opponents. They've gotta be just right. :P

However, my interest in OpenAL is more concerned with the positioning of sounds than the actual sound effects themselves. Proper 3D audio also adds greatly to the experience - I know because I've done a lot of research and experimenting in this area. It's often very difficult to get 3D headphone surround sound working in games that don't support OpenAL and usually it doesn't work properly. But with games that support OpenAL, it's usually very easy and provides the best quality results.

simon kamakazi · January 2010

interesting,

passed this onto charlie, he takes care of all the sound code.

i think in a MP game like NS2 judging distance and derection of sounds is very important.

right now we have the obvious left right panning, but also, ocllusion (basicaly low pass filter that opens and closes as a function of distance) and room reverbs that increase as u move away from a sound. right now this works for key sounds only but i want to have these effects on more sounds, we have to see how much of an impact this has on CPU and RAM usage tho..
also we are using a distant variant of a the MG fire sound that crossfades with the close one as u move up to it

so the character, not just the volume, of important sounds will change as u get further away from them, this should help ppl judge how far away as well as in what derection enemies are.

SgtBarlow · January 2010

It would be nice to have my Creative sound card utilized by NS2, Just like it is with Battlefield 2, 2142 etc.
openAL allows you to use the soundcards own built in xRAM and Processor.

I have an x-fi Elite Pro:
Sound Blaster X-Fi features for Gaming

* A completely re-engineered game audio processing engine utilizing the Creative X-Fi audio processor allows Sound Blaster X-Fi Fatal1ty FPS to deliver the fastest gaming performance ever seen, providing more than a 15% performance boost over motherboard audio solutions while simultaneously delivering full audio effects.
* X-RAM allows developers to deliver even higher quality audio samples that can be loaded into dedicated X-RAM (Xtreme Fidelity RAM) rather than system RAM, which would affect overall performance. In certain implementations it can further boost performance beyond the standard Sound Blaster X-Fi technology.
Note:
X-RAM is only available on Sound Blaster Fatal1ty FPS and Sound Blaster Elite Pro products.

This sound card improved my performance noticeably in supported games on my older computer cause it took the job of Audio from the CPU and System RAM.

Besides that, openAL is free as far as i can see so far.
<a href="http://connect.creativelabs.com/openal/OpenAL%20Wiki/Games.aspx" target="_blank">Open AL games</a>

Not clear on the FMOD licenses but i think it goes something like:
You can use it for free in a free game otherwise you have to buy a <Commercial License>/<Causual License (Sales Restricted to a max of $20)> per Application > Per Platform.
Seeing how the special edition was sold for $40, I suspect the Commercial License was bought. about $4500?, 1 for the Game, 1 for the editor?
Then i think to push out the game and editor not the server, on Linux, another $3000. Same again to put it out on Mac.
Double those figures if its includeing the Designer.
Aint a big deal if you got the funds comming in.

I am hopeing that you can and will use the possible access available in Fmod to openAL.

<b>I would like to know why FMOD sdk would make a better choice over the openAL sdk on the codeing scene because I dont know yet myself.</b>
I havent got there yet. tried both cant get either of the bloody things to play a wav.

Tephra · January 2010

One of the key elements that NS2 has going for it is the lighting and setting of the game. They have the opportunity to make one of the most visceral, intense mp games out there, if they can get the sound right. Any of you who have created some spooky areas in the editor can understand what I'm saying. You can just imagine that moment when youre a marine in a dim lit room and you hear a noise that brings you to attention.

And of course good spatial sound has a strong impact on competitive gaming as well.

Kouji_San · January 2010

Sounds along with visuals are the things that stick in the mind of people, anyone who has ever played doom1/2 will recognize the door, zombieman, shotgun guy alert and imp death sounds from movies. NS1 already has a lot of those sounds, so not only the sound processing should be awesome, the sounds themselves should be very unique as well.

spellman23 · January 2010

Sounds pretty awesome. Dunno how high on the priority this extra functionality is, but it would be kinda awesome.

Truth be told, I think I've trained myself so that even with just LR panning I can tell if stuff is behind/above/etc. I happen to know that most games use certain types of echoing, volume attenuation, and such to help give more forward/backward capabilities, but it certainly isn't as high of a priority these days. Very rarely do you hear about the sound quality of a game unless it's horrid, and it typically isn't a selling metric. However, shaders are.

Blame the consumers I guess.

-WildCat- · January 2010

In my initial post, I mentioned Rapture3D - an OpenAL driver that can produce 3D headphone surround sound. I've made a video to demonstrate this effect.

<a href="http://www.youtube.com/watch?v=lqqiIR017SQ" target="_blank">Youtube - Rapture3D Audio Demonstration in UT3</a>

<div class='quotetop'>QUOTE (Video description)</div><div class='quotemain'>Rapture3D is an OpenAL driver that can produce 3D headphone surround sound using HRTFs. In this video, I've attempted to demonstrate this effect by comparing Rapture3D sound with the standard Unreal Tournament 3 sound. Unreal Tournament 3 supports OpenAL so you can use the Rapture3D driver as the sound provider by editing your config file.

Notice how the sound positioning in all the 'Generic Software' clips is very "flat". It only positions sounds using simple left-to-right panning. Then notice how 'Rapture3D' positions sounds all around you, allowing you to distinguish their positions in space much more precisely. The difference between in-front and behind, as well as above and below, is quite clear.

When you've finished watching this video, rewind it and watch it again ... this time with your eyes closed.

This video was created with the "User" version of Rapture3D. The speaker layout was set to "Headphone Stereo (Compat.)" and the decoder method was set to "HRTF (Green)".</div>
I wanted to include a demonstration of Creative's CMSS-3D as well but my FRAPS recordings came out silent with that turned on. It doesn't matter, though, because the effect of CMSS-3D is almost the same as Rapture3D.

monopolowa · January 2010

That definitely makes a difference. Would be nice if this makes it in the game in some form.

Triggerman · January 2010

I'm a believer after that video WildCat.
It's pretty darn convincing compared to the regular audio!
How would this affect performance you think? I use a laptop and I guess that this would require a "real" sound card to work?

SgtBarlow · January 2010

Should not be an issue at all, There should always be the required options in the settings of the game to suit your computer.
Hardware Acceleration is always better than Generic Software but low end sound cards dont have many channels, some can have < 64 channels, too many sounds at once and you get some awfull distortion even if your CPU is okay. If you have plenty of CPU and RAM you will be okay and might want to use software mode if you can afford it but you loose that 3D sound quality but gain a lot more channels (upto 256). Supreme Commander will eat the CPU in this event with an enormous battle.

BF2 could detect if you had a Creative x-Fi card, this unlocked the ULTRA Sound quality option for the game and then supporting EAX effects. It's ace.
There are other games like this, then there are games that only have volume options (sux).

simon kamakazi · January 2010

interesting vid wildcat,

it sounds alot more convincing for sounds behind u then regular audio, but i didnt get the above/below effect, did any one else hear that?

also i noticed the weapon fire sound get alot thinner and whimpy with the 3D stuff happening. im assuming this is a phasing issue, bass canceling out ect.

interesting for sure.

SgtBarlow · January 2010

I got the above and below sound, You really need to have a supporting card and 5.1 headset to get above and below.
What did you listen to it with?

Renegade. · January 2010

surround sound headsets are a joke. what's next, in-ear subwoofers?

schkorpio · January 2010

<div class='quotetop'>QUOTE (R_e_n_e_g_a_d_e @ Jan 25 2010, 02:38 AM) <a href="index.php?act=findpost&pid=1748928"><{POST_SNAPBACK}></a></div><div class='quotemain'>surround sound headsets are a joke. what's next, in-ear subwoofers?</div>

you'd be suprised how well it works actually - its kind of like when everyone thinks that 3D glasses are dumb, and then they see avatar and they are like "wow"

-WildCat- · January 2010

<div class='quotetop'>QUOTE (Triggerman @ Jan 23 2010, 10:08 PM) <a href="index.php?act=findpost&pid=1748803"><{POST_SNAPBACK}></a></div><div class='quotemain'>How would this affect performance you think? I use a laptop and I guess that this would require a "real" sound card to work?</div>
I'm not sure how much Rapture3D affects performance. If I find the time, I might do some benchmarks. I can say this, however: It does <i>not</i> require a "real" sound card. The Rapture3D OpenAL driver that I used to create <a href="http://www.youtube.com/watch?v=lqqiIR017SQ" target="_blank">that video</a> is a software driver and it uses just your CPU.

<div class='quotetop'>QUOTE (simon kamakazi @ Jan 24 2010, 08:37 AM) <a href="index.php?act=findpost&pid=1748871"><{POST_SNAPBACK}></a></div><div class='quotemain'>it sounds alot more convincing for sounds behind u then regular audio, but i didnt get the above/below effect, did any one else hear that?</div>
I got the 'above' effect although I agree that the 'below' effect was a bit dubious. Bear in mind that results may vary from person to person. It depends on your head and ear shape. You will get better results if your head and ear shape is similar to that of the person or model that they used when taking readings for creating their HRTF algorithms. Rapture3D comes with 5 different HRTF settings to choose from, each based on different data sets.

<div class='quotetop'>QUOTE (SgtBarlow @ Jan 24 2010, 05:36 PM) <a href="index.php?act=findpost&pid=1748917"><{POST_SNAPBACK}></a></div><div class='quotemain'>I got the above and below sound, You really need to have a supporting card and 5.1 headset to get above and below.
What did you listen to it with?</div>
You don't need a 5.1 headset. The audio in <a href="http://www.youtube.com/watch?v=lqqiIR017SQ" target="_blank">my YouTube video</a> is stereo. Any stereo headset will be fine.

Heyman · January 2010

I don't completely understand the conversation going on in this thread, but from what I've learned, I'd really like to support this.

I've always relied on audio to find those skulks creeping up on me. Playing NS helped me with a lot of other First Person Shooters in that way.

Primarily, though, I really want that audio for the immersive aspect.

Renegade. · January 2010

<div class='quotetop'>QUOTE (schkorpio @ Jan 24 2010, 02:43 PM) <a href="index.php?act=findpost&pid=1748976"><{POST_SNAPBACK}></a></div><div class='quotemain'>you'd be suprised how well it works actually - its kind of like when everyone thinks that 3D glasses are dumb, and then they see avatar and they are like "wow"</div>
suprised? no, but I agree with the last part - anyone who went "wow" after seeing maybe 5-7 scenes rendered in quasi-3D is the same type of person who'd wow at a headset containing the same number of speakers.

spellman23 · January 2010

For about 90% of the people you can get pretty good approximations even of vertically with straight stereo headphones and some audio processing. Getting the 4 speakers for each ear headphones, in my opinion, isn't worth the extra money. But that just may be my asian penny-pinching side.

Draco_2k · January 2010

<div class='quotetop'>QUOTE (spellman23 @ Jan 25 2010, 09:28 PM) <a href="index.php?act=findpost&pid=1749122"><{POST_SNAPBACK}></a></div><div class='quotemain'>Getting the 4 speakers for each ear headphones, in my opinion, isn't worth the extra money.</div>
Nothing in the audio department is worth the extra money. It's all just luxury items: mobo cards today are great, and even the cheapest speakers/headphones have great quality off the bat.

schkorpio · January 2010

<div class='quotetop'>QUOTE (R_e_n_e_g_a_d_e @ Jan 25 2010, 11:11 AM) <a href="index.php?act=findpost&pid=1749024"><{POST_SNAPBACK}></a></div><div class='quotemain'>suprised? no, but I agree with the last part - anyone who went "wow" after seeing maybe 5-7 scenes rendered in quasi-3D is the same type of person who'd wow at a headset containing the same number of speakers.</div>
don't try to be cooler than everyone here - you are on the internet, on a gaming website, posting on the forums about unreleased game.

Renegade. · January 2010

<div class='quotetop'>QUOTE (schkorpio @ Jan 25 2010, 02:09 PM) <a href="index.php?act=findpost&pid=1749134"><{POST_SNAPBACK}></a></div><div class='quotemain'>don't try to be cooler than everyone here - you are on the internet, on a gaming website, posting on the forums about unreleased game.</div>
everyone here? last I checked only you were in awe by surround sound headsets and pseudo-3D movies. Then again, industry needs people like you to drive the bottom line.

schkorpio · January 2010

<div class='quotetop'>QUOTE (R_e_n_e_g_a_d_e @ Jan 26 2010, 12:18 PM) <a href="index.php?act=findpost&pid=1749185"><{POST_SNAPBACK}></a></div><div class='quotemain'>everyone here? last I checked only you were in awe by surround sound headsets and pseudo-3D movies. Then again, industry needs people like you to drive the bottom line.</div>

its not my fault you have sand in your vag1na

OpenAL

Comments