Hi Philip, That's a good question. I don't know if OpenAL supports customn DSP effects or not, but I can check. In any case that would only be half the problem here. I'm currently using a cross-platform audio library called sfml-audio which is basically a nice front-end for OpenAL. The SFML developer has added all the necessary code to load wav files, ogg files, and various other file types and then loads them into OpenAL's sound buffers for playback and positioning. Plus has added support for streaming and that sort of thing. In other words it is basically the open source equal to your PB Streemway library minus the sound encryption and it uses OpenAL rather than DirectSound. So if sfml-audio doesn't support custom DSP but OpenAL does then it would be up to me to reinvent the wheel by creating my own Streemway or sfml-audio type front-end to get a simple stereo pan effect. Definitely not a very happy thought seeing as such a project would take a good month to create if not longer.
As for justifying a cross-platform engine what can I say? In my opinion the fact that my wife and I have chosen to go Linux but most of my customers still use Windows is justification enough. Its like what would be the point spending months, even years, creating games that would only run on Windows when three out of four computers my wife and I own now all run Linux. The only reason we have kept that one Windows system around is because we own some expensive software that we can still use like Soundforge, Visual Studio Pro, as well as various games that won't run on Linux and still is of personal use to us. As good as Linux is admitedly there are certainly apps you can't find for Linux such as the Halmark software for creating personalized holiday gift cards that my wife likes to use. for that we can justify keeping one Windows system around, but not maintaining three or four computers with Windows software on it. That obviously gets expensive. Especially in light of the fact more and more developers are going the route of Microsoft and licensing software for a single computer. So I have elected to take whatever time and energy is necessary to modify my Genesis Engine, which was written in C++ anyway, to use non-proprietary APIs like SFML so I could build high quality Linux games for myself while still being able to sell to a mostly Windows market. It is buggy right now, but I'm sure I'll eventually get it all working in time. Cheers! On 10/5/10, Philip Bennefall <[email protected]> wrote: > Hi Thomas, > > Here's a quick thought for you to ponder. Does OpenAl have support for > custom dsp? A callback interface or similar for each sound that enables you > to add your own dsp effects or filters to the audio in real-time? If so, you > could write a pan effect and simply layer it on top of the sound system and > you'd get a perfect pan effect just like in DirectSound, without having to > modify the libraries in the slightest. The actual panning, as you know, is > trivial math; the only concern is whether you can get at the raw audio data > as it is being played, and whether you can do so not only staticly but also > in real-time in order to make rapid/dynamic changes. XAudio2 supports this, > and so this is what I plan to do for Streemway if the XAudio2 3d renderer > turns out to be unable to reproduce panning accurately which seems to be the > case with OpenAl. > > I think the idea of a cross platform game engine is great, if you can > justify the extra time spent etc. Good luck! > > Kind regards, > > Philip Bennefall --- Gamers mailing list __ [email protected] If you want to leave the list, send E-mail to [email protected]. You can make changes or update your subscription via the web, at http://audyssey.org/mailman/listinfo/gamers_audyssey.org. All messages are archived and can be searched and read at http://www.mail-archive.com/[email protected]. If you have any questions or concerns regarding the management of the list, please send E-mail to [email protected].
