Just taking a look into the current sound libs. And of course we're using OpenAL there. So why should we actually when using OpenAL, erm actually erm, use it???? When looking at lib/sound/openal_track.c:sound_SetObjectPosition() I'm getting a headache.
Rather than just simply setting the sound-generating object's location using an OpenAL API call, and let OpenAL handle all the gain and volume attenuation stuff, this code does the job which OpenAL should do (and is probably better at considering it uses hardware acceleration where possible). That function first calculates the distance between listener and sound source (Pythagoras like; using a quadratic formula then sqrt) . Then based upon that it calculates the sound's gain based upon the distance and tells OpenAL to use that gain. Then it makes a final call to the OpenAL API to set the position of that sound's source. Since one of the things sound_InitLibrary() does however that last call won't have any effect because it disables OpenAL's distance calculation by this call: > alDistanceModel( AL_NONE ); What I tried to explain here, is that the current sound implementation only uses OpenAL as a sound mixer (which SDL happens to be capable of just the same) just for playing different sounds in parallel. The same distance computation is btw provided by OpenAL when the distance model is set to AL_LINEAR_DISTANCE and the sound source's AL_MAX_DISTANCE=1.0, AL_REFERENCE_DISTANCE=0.0 and AL_ROLLOFF_FACTOR=ATTENUATION_FACTOR (ATTENUATION_FACTOR is currently defined to 0.0003 which is _very_ low). Therefore I propose a major overhaul/reimplementation for the sound lib (probably best in a separate branch). So please give me your pros and cons to this proposal (or its grounds). -- Giel
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