Re: [Flightgear-devel] FG - FGFX class
I'd like to ask people have relations to FG sound development. Have yours seen osgAL library(plugin) http://www.vrlab.umu.se/research/osgAL/ ? It seems to have add OpenAL functionality and transparent bindings to OSG objects right into OSG. An the other end - it produces yet another dependency. If someone has played around with osgAL - do you have some opinion about that project ? Regards, Vladimir - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Maik Justus wrote: no. The Doppler problems are due to OpenAL bugs and limitations. On most systems (at least at all which are using Open AL software Doppler calculation) I got strange effects. On Linux systems a workaround was to use only the relative velocity of listener and sound, which is Hm, that sounds bad indeed. But FlightGear code at this time doesn't lock listener orientation to viewer orientation. So in theory it could be you are looking in one direction but get the sounds as if you were looking in another direction. physically not correct. But on windows even this approach results is strange effects. There I use my own software implementation in simgear and pass the calculated pitch and volume to Open AL. But Open AL clamps the pitch factor (If I remember correctly to 0.5 ... 2), and That's correct for the Creative implementation, they introduced this for their hardware limitations although the specs doesn't say it should be clamped but it doesn't say it may not be clamped either. This is one such case where having a monopolist is a bad thing. additionally many aircrafts modify the pitch by them self. This limits the Doppler effect in Flightgear. Indeed. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
* Maik Justus -- Thursday 23 October 2008: Melchior sent me a note, that actual Open AL might be less buggy, but he still noticed strange effects. I guess we have to define what actual means here. As far as I know by now, there are three variants: (a) original OpenAL by Loki (as Erik pointed out recently) (b) official OpenAL by Creative (continued from (a)). Development stalled, not very actively maintained; last commits in May? Broken Doppler on Windows? Most people used to be using this until not too long ago. (c) new OpenAL-Soft (http://kcat.strangesoft.net/openal.html) forked from (b)/Win32. Working Doppler (according to its author :-) Debian derivatives (Ubuntu) seem to have switched to this. And no: I didn't notice strange effects in (c). This was referring to our current configuration with our workaround for Windows and probably using (b). *This* doesn't work correctly, according to Vivian. The problem is, that we can probably not distinguish between them. Should/can we remove all workarounds and require (c)? Assuming that it actually works, of course. Advantage: it's actively maintained. The main developer answered only hours after I had reported a possible bug, and he even checked out and commented on the SimGear code, although I had only mentioned FlightGear. Almost scary. ;-) m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: I guess we have to define what actual means here. As far as I know by now, there are three variants: (a) original OpenAL by Loki (as Erik pointed out recently) (b) official OpenAL by Creative (continued from (a)). Development I have tot state that the Creative implementation is a newly created version by them. So there is no GPL infragmentation. This is their official implementation which has hardware support for their soundcards. stalled, not very actively maintained; last commits in May? Broken Doppler on Windows? Most people used to be using this until not too long ago. Actually this part still belongs to a) (c) new OpenAL-Soft (http://kcat.strangesoft.net/openal.html) forked from (b)/Win32. Working Doppler (according to its author :-) Debian derivatives (Ubuntu) seem to have switched to this. and there is (d) A complete rewrite of OpenAL done by me, not released yet and still figuring out how to best push this. I've used this one for at least half a year now when running FlightGear. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
* Erik Hofman -- Friday 24 October 2008: (d) A complete rewrite of OpenAL done by me, not released yet and still figuring out how to best push this. I've used this one for at least half a year now when running FlightGear. Frankly, I don't see how (d) can compete with (c), which is used and cared for by several Linux distributions as well as used and tested by several million people. Do we really want to pull in maintainership of our own OpenAL implementation (for no good reason)? And that after you were absent for a few years and just threatened to leave again for good? What if people start to complain about FlightGear's OpenAL not working with the latest MSys/Cygwin/OS-XI or Microsoft Fluffy[TM]? Sorry, but that sounds like a suboptimal deal. But I won't do the work either way, so I better shut up now. m. :-} - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: Frankly, I don't see how (d) can compete with (c), which is used and cared for by several Linux distributions as well as used and tested by several million people. Do we really want to pull in maintainership of our own OpenAL implementation (for no good reason)? And that after you were absent for a few years and just threatened to leave again for good? What if people start to complain about FlightGear's OpenAL not working with the latest MSys/Cygwin/OS-XI or Microsoft Fluffy[TM]? Sorry, but that sounds like a suboptimal deal. But I won't do the work either way, so I better shut up now. I never said I wanted to put my own implementation into FlightGear.. Still, there is a new option available soon. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Did I say I'd shut up now? Bah ... ;-) * Erik Hofman -- Friday 24 October 2008: I never said I wanted to put my own implementation into FlightGear. Still, there is a new option available soon. True, I'm sorry. The ultimate question is really only: can we drop our current workarounds for buggy implementations, and rely on a clean spec-compliant (i.e. working) OpenAL version, and point people to an URL where this can be found for optimal results. Ideally, this shouldn't be an ancient and unmaintained implementation. m. BTW: regarding this: * Erik Hofman -- Friday 24 October 2008: * * Melchior FRANZ -- Friday 24 October 2008: (b) official OpenAL by Creative (continued from (a)). Development stalled, not very actively maintained; last commits in May? Broken Doppler on Windows? Most people used to be using this until not too long ago. Actually this part still belongs to a) OpenSuSE, for example, does not seem to use (a), but (b). And the officially sounding URL http://www.openal.org/ is also about (b). - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: Frankly, I don't see how (d) can compete with (c), which is Yeah yeah, By the second time I got the message ;) Erik (Sorry, I couldn't resist) - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
* Melchior FRANZ -- Friday 24 October 2008: Should/can we remove all workarounds and require (c)? Just for clarification: all versions should really be compatible, anyway. So there wouldn't be a requirement to install a particular one. The question is only, if one implementaiton is fully spec compliant, and fg could drop all workarounds and recommend using that version. Then people could decide to install that implementation and have working Doppler, or use another one and live with the bugs and noises. :-) m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: True, I'm sorry. The ultimate question is really only: can we drop our current workarounds for buggy implementations, and rely on a clean spec-compliant (i.e. working) OpenAL version, and point people to an URL where this can be found for optimal results. Ideally, this shouldn't be an ancient and unmaintained implementation. I'm all for it, the remaining problem might be hardware accelerated 3d audio support from the Creative drivers. If that version fails, then what? Eril - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
* Erik Hofman -- Friday 24 October 2008: Yeah yeah, By the second time I got the message ;) In case you are referring to mail duplicates: As you can see on the message ids, I didn't send it twice. This is a bug in the sourceforge.net mail handling: http://sourceforge.net/tracker/?func=detailatid=21aid=2147569group_id=1 m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
* Erik Hofman -- Friday 24 October 2008: the remaining problem might be hardware accelerated 3d audio support from the Creative drivers. If that version fails, then what? Ugh ... no idea about that. Wouldn't implementations like openal-soft care for that as well? (Not that I've found any hint pointing in that direcdtion.) And if not, ignoring that sounds better to me than working around a broken vendor-specific implementation. m. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: * Erik Hofman -- Friday 24 October 2008: the remaining problem might be hardware accelerated 3d audio support from the Creative drivers. If that version fails, then what? Ugh ... no idea about that. Wouldn't implementations like openal-soft care for that as well? (Not that I've found any hint pointing in that direcdtion.) And if not, ignoring that sounds better to me than working around a broken vendor-specific implementation. OpenAL-Soft now is independent from the Creative version. So no luck there (unless the binary drivers are combined with OpenAL-Soft which should be possible as far as I know). But I think I agree that working around a broken implementation should be avoided. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Melchior FRANZ wrote: * Erik Hofman -- Friday 24 October 2008: Yeah yeah, By the second time I got the message ;) In case you are referring to mail duplicates: As you can see on the message ids, I didn't send it twice. This is a bug in the sourceforge.net mail handling: http://sourceforge.net/tracker/?func=detailatid=21aid=2147569group_id=1 I know :) I was just teasing. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
On 22 Oct 2008, at 22:00, Vladimir Karmishin wrote: Right now, I'm not completely understand how does FGFX class work, it seems it standing for some kind of global sound proxy between FG and SimGear. If somebody has worked with or on this class - then I'd like to ask him for a little help. I need any thoughts, imaginations about which way can it be modified to let it work with multiple 3d sound emitters. They way I thought about doing this was to extend the SimGear classes with a 'SGSoundSource' object, registered with the sound manager. Samples would be played from a source, and sources would have position / velocity / etc. Then you'd make AIBase or AIModel own a SGSoundSource, and use that for the sound generation. Internally, you'd need to do the work to convert the public pos/ orientation/velocity data of each SGSoundSource into the format expected by OpenAL. That's probably a little awkward but not intrinsically hard - especially since there are many, many helpers and examples already to show converting coordinate systems (geodetic - cartesian, for example). This is probably not the simplest way to do it, but it's object- orientated, and opens up some possibilities in the future - eg giving eg sound source its own Nasal hash/functions, so scripts can just play a sound on an AI model. If this seems like a reasonable idea, I can post some headers and pseudo-code. Regards, James - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Hi James ! Thank you for your help ! In fact, i'm thought about extending FGFX functionality with some members, like adding some members to it, like FGFX::ConvertGLCoordinates, FGFX::BindToModelNode, etc... That little hack I published before - is based at approach like you told, but at my oppinion it was a really bad example of code, due it has very far relation to real OOP. If we has FGFX, than we should avoid to embedd SG classes directly, instead embed them in FGFX, IMHO. There's a function in SimGear, SGSoundMgr::set_source_pos_all. As far as I understand, it deals with all of the sources a listed in source map. Maybe there'll be a need of writing of per-source based function. In fact i'm in trouble with this set_source_pos_all, and experimenting with it. Using multiple 3d sound sources can be a very cool and handful thing. Imagine, you have B737 and you can bind sound emitters right to engines, not fuselage, or cockpit. And hear them right as supposed to sound. Or you can have Il-62 model, with 4 engines at his tail - and of course they will sound the other way as B737 ones. Etc, etc, etc... Regards, Vladimir On Oct 23, 2008, at 9:41 AM, James Turner wrote: They way I thought about doing this was to extend the SimGear classes with a 'SGSoundSource' object, registered with the sound manager. Samples would be played from a source, and sources would have position / velocity / etc. Then you'd make AIBase or AIModel own a SGSoundSource, and use that for the sound generation. Int - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Vladimir Karmishin wrote: Hello ! I'm still digging into FlightGear sound subsystem. :-) Today, I make a small modification in AI Aircrafts, to let them produce some noise. This encouraged me to look at the FGFX change I made before but which turned out to be less than ideal. I think I'm slowly getting at what is happening. If I get this sorted out adding sound effects to models should be easy. I'll let you know how things turn out. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
On Oct 23, 2008, at 11:12 AM, Erik Hofman wrote: This encouraged me to look at the FGFX change I made before but which turned out to be less than ideal. I think I'm slowly getting at what is happening. If I get this sorted out adding sound effects to models should be easy. I'll let you know how things turn out. Erik Erik, thank you for the answer. In fact - i'm started work on re-implementation of OAL in SimGear. My vision on it - it should be more OOP-is (however, I'm not a big OOP addict), and transparent. In ideal - we should be able just to write some (in pseudocode) CObject.Engine[1]-MapSoundSource(CFM_sound); - and get it work. As far as I know - You're the developer of current FG sound subsystem. Just to not do the same work twice - maybe we can/should co-operate, and bring out something together ? What do you think about it ? Working for a years as sound engineer, I have some imaginations about how sound should work, and maybe my experience can be handful. At other end - I abadoned programming in 2004, and now I'm slowly getting back, but as hobby, but there're lot of things I forgot, and even more of them I never knew - and your experience can solve a lot of questions. Regards, Vladimir - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Vladimir Karmishin wrote: Can you rememer back, is SGSoundMgr::set_source_pos_all( ALfloat *pos ); is sort of hack, assuming everything is happening inside cabin, or it's just sources enumerator, which pass through a map of loaded sounds updating their positions ? Of course I can play around with code using debugger, but I guess it's easier to ask here. :-) I don't even think I added that function.. But it would be best if it sets everything related to the aircraft as an offset to a reference point. Then it wouldn't matter if it's inside the cockpit or outside, it just moves alls related sounds with the aircraft. BTW. Looking at the code some further it would be best to split op the position and velocity code for the listener (and move it to the viewer code) and the model and move it to the model code (being the current model or an AI model.) Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
On Thu, 23 Oct 2008 10:10:42 +0200, Vladimir wrote in message [EMAIL PROTECTED]: Hi James ! Thank you for your help ! In fact, i'm thought about extending FGFX functionality with some members, like adding some members to it, like FGFX::ConvertGLCoordinates, FGFX::BindToModelNode, etc... That little hack I published before - is based at approach like you told, but at my oppinion it was a really bad example of code, due it has very far relation to real OOP. If we has FGFX, than we should avoid to embedd SG classes directly, instead embed them in FGFX, IMHO. There's a function in SimGear, SGSoundMgr::set_source_pos_all. As far as I understand, it deals with all of the sources a listed in source map. Maybe there'll be a need of writing of per-source based function. In fact i'm in trouble with this set_source_pos_all, and experimenting with it. Using multiple 3d sound sources can be a very cool and handful thing. Imagine, you have B737 and you can bind sound emitters right to engines, not fuselage, or cockpit. And hear them right as supposed to sound. ..keep in mind sound moves thru the airframe structure too, and much faster than it does thru the air flowing around the aircraft, imagine e.g. propeller noise heard in a F-16 from a Tu-95, or heard in a Spit from a FW-190 playing chicken, or in a B-17 combat box formation. Lovely can of worms. ;o) Or you can have Il-62 model, with 4 engines at his tail - and of course they will sound the other way as B737 ones. Etc, etc, etc... Regards, Vladimir On Oct 23, 2008, at 9:41 AM, James Turner wrote: They way I thought about doing this was to extend the SimGear classes with a 'SGSoundSource' object, registered with the sound manager. Samples would be played from a source, and sources would have position / velocity / etc. Then you'd make AIBase or AIModel own a SGSoundSource, and use that for the sound generation. Int -- ..med vennlig hilsen = with Kind Regards from Arnt... ;o) ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
..keep in mind sound moves thru the airframe structure too, and much faster than it does thru the air flowing around the aircraft, imagine e.g. propeller noise heard in a F-16 from a Tu-95, or heard in a Spit from a FW-190 playing chicken, or in a B-17 combat box formation. Lovely can of worms. ;o) Doppler is responsible of such effects, and it's hard-coded into OpenAL. Regards, Vladimir Or you can have Il-62 model, with 4 engines at his tail - and of course they will sound the other way as B737 ones. Etc, etc, etc... Regards, Vladimir On Oct 23, 2008, at 9:41 AM, James Turner wrote: - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Vladimir Karmishin wrote: I need any thoughts, imaginations about which way can it be modified to let it work with multiple 3d sound emitters. Reading this again there might be some confusion; aircraft can have multiple 3d sound emitters already, they are just tied to the main aircraft right now (and the listener is always facing the main model, this is probably why doppler doesn't function too well). But you can already define the position an direction of each sound effect. The remaining problem is to make the AI models also emit sound effects. Erik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
On Thu, Oct 23, 2008 at 11:47 AM, Erik Hofman wrote: Vladimir Karmishin wrote: I need any thoughts, imaginations about which way can it be modified to let it work with multiple 3d sound emitters. Reading this again there might be some confusion; aircraft can have multiple 3d sound emitters already, they are just tied to the main aircraft right now (and the listener is always facing the main model, this is probably why doppler doesn't function too well). But you can already define the position an direction of each sound effect. The remaining problem is to make the AI models also emit sound effects. If I recall, your own aircraft sounds are setup relative to an ear location of (0,0,0). In the openal 3d world, the way we had things originally setup anyway, the current view location always corresponded to an ear location of (0,0,0). Then aircraft sounds (engines, etc.) were fixed relative to 0,0,0 and never moved. This worked pretty well. If you start moving the ear location in real world space, and then also moving the sounds in real world space, I don't know exactly what will happen, but if you don't move *everything* in perfect lock step, you will definitely get a strange warbling effect as you get an audio version of the position of sounds jittering a little closer or a little further every frame in a somewhat random fashion. Even if you move the sounds and listener in perfect lock step, I don't know how well openal handles that? I have a side question on OpenAL. Is there a way to size the audio buffer of data that gets sent to the sound device? In plib we could set the number of seconds that were buffered in the queue (and we set that to something longer than the time it took to draw a frame, but not too long or there would be noticable delay between an action and the change in sound.) I have a couple systems here that are a bit older and lower performance, and we are hearing frequent breaks in the openal audio output ... as if the audio buffer is getting starved and the sound is momentarily interrupted. Does anyone know if there's a way to increase the buffer size in openal to eliminate the chance that the buffer could be completely emptied before more data can be stuff into it? Thanks, Curt. -- Curtis Olson: http://baron.flightgear.org/~curt/ - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
On Thu, 23 Oct 2008 18:05:30 +0200, Vladimir wrote in message [EMAIL PROTECTED]: ..keep in mind sound moves thru the airframe structure too, and much faster than it does thru the air flowing around the aircraft, imagine e.g. propeller noise heard in a F-16 from a Tu-95, or heard in a Spit from a FW-190 playing chicken, or in a B-17 combat box formation. Lovely can of worms. ;o) Doppler is responsible of such effects, and it's hard-coded into OpenAL. ..lovely, it can handle things like shock waves from propeller blades meeting those from AA gun fire? Sounds sort of whip double strike like, if you haven't heard it in RL, from each grenades bow and tail wave meeting the propeller blade tip waves, I used to fly R/C AA target drones way back in the Cold War. ;o) -- ..med vennlig hilsen = with Kind Regards from Arnt... ;o) ...with a number of polar bear hunters in his ancestry... Scenarios always come in sets of three: best case, worst case, and just in case. - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
Re: [Flightgear-devel] FG - FGFX class
Hi Erik, Erik Hofman schrieb am 23.10.2008 18:47: Vladimir Karmishin wrote: I need any thoughts, imaginations about which way can it be modified to let it work with multiple 3d sound emitters. Reading this again there might be some confusion; aircraft can have multiple 3d sound emitters already, they are just tied to the main aircraft right now (and the listener is always facing the main model, this is probably why doppler doesn't function too well). no. The Doppler problems are due to OpenAL bugs and limitations. On most systems (at least at all which are using Open AL software Doppler calculation) I got strange effects. On Linux systems a workaround was to use only the relative velocity of listener and sound, which is physically not correct. But on windows even this approach results is strange effects. There I use my own software implementation in simgear and pass the calculated pitch and volume to Open AL. But Open AL clamps the pitch factor (If I remember correctly to 0.5 ... 2), and additionally many aircrafts modify the pitch by them self. This limits the Doppler effect in Flightgear. Melchior sent me a note, that actual Open AL might be less buggy, but he still noticed strange effects. But you can already define the position an direction of each sound effect. Yes, and many aircrafts make use of this, e. g. the S58 or the Bo105. The remaining problem is to make the AI models also emit sound effects. Erik Maik - This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100url=/ ___ Flightgear-devel mailing list Flightgear-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/flightgear-devel
