Rework manual rolloff handling

For distance models OpenAL doesn't handle, alter the source's distance to get
the appropriate attenuation instead of the source's gain.
This commit is contained in:
Chris Robinson 2014-06-20 04:38:48 -07:00
parent ef7ce41d07
commit f0c9aae670
2 changed files with 92 additions and 79 deletions

View file

@ -101,7 +101,7 @@ struct FISoundChannel
FRolloffInfo Rolloff;
float DistanceScale;
float DistanceSqr;
bool ManualGain;
bool ManualRolloff;
};

View file

@ -818,8 +818,6 @@ void OpenALSoundRenderer::SetSfxVolume(float volume)
alcSuspendContext(Context);
alSourcef(source, AL_MAX_GAIN, volume);
if(schan->ManualGain)
volume *= GetRolloff(&schan->Rolloff, sqrt(schan->DistanceSqr));
alSourcef(source, AL_GAIN, volume * schan->Volume);
}
schan = schan->NextChan;
@ -1126,12 +1124,12 @@ FISoundChannel *OpenALSoundRenderer::StartSound(SoundHandle sfx, float vol, int
if(!chan) chan = S_GetChannel(MAKE_PTRID(source));
else chan->SysChannel = MAKE_PTRID(source);
chan->Rolloff.RolloffType = ROLLOFF_Linear;
chan->Rolloff.MaxDistance = 1000.f;
chan->Rolloff.RolloffType = ROLLOFF_Log;
chan->Rolloff.RolloffFactor = 0.f;
chan->Rolloff.MinDistance = 1.f;
chan->DistanceScale = 1.f;
chan->DistanceSqr = 1.f;
chan->ManualGain = false;
chan->DistanceSqr = 0.f;
chan->ManualRolloff = false;
return chan;
}
@ -1140,8 +1138,7 @@ FISoundChannel *OpenALSoundRenderer::StartSound3D(SoundHandle sfx, SoundListener
FRolloffInfo *rolloff, float distscale, int pitch, int priority, const FVector3 &pos, const FVector3 &vel,
int channum, int chanflags, FISoundChannel *reuse_chan)
{
float dist_sqr = (pos - listener->position).LengthSquared() *
distscale*distscale;
float dist_sqr = (pos - listener->position).LengthSquared();
if(FreeSfx.size() == 0)
{
@ -1156,61 +1153,80 @@ FISoundChannel *OpenALSoundRenderer::StartSound3D(SoundHandle sfx, SoundListener
return NULL;
}
float rolloffFactor, gain;
bool manualGain = true;
float rolloffFactor = 1.f;
bool manualRolloff = true;
ALuint buffer = GET_PTRID(sfx.data);
ALint channels = 1;
alGetBufferi(buffer, AL_CHANNELS, &channels);
ALuint source = FreeSfx.back();
alSource3f(source, AL_POSITION, pos[0], pos[1], -pos[2]);
alSource3f(source, AL_VELOCITY, vel[0], vel[1], -vel[2]);
alSource3f(source, AL_DIRECTION, 0.f, 0.f, 0.f);
alSourcei(source, AL_SOURCE_RELATIVE, AL_FALSE);
alSourcei(source, AL_LOOPING, (chanflags&SNDF_LOOP) ? AL_TRUE : AL_FALSE);
// Multi-channel sources won't attenuate in OpenAL, and "area sounds" have
// special rolloff properties (they have a panning radius of 32 units, but
// start attenuating at MinDistance).
if(channels == 1 && !(chanflags&SNDF_AREA))
{
if(rolloff->RolloffType == ROLLOFF_Log)
{
if(AL.EXT_source_distance_model)
alSourcei(source, AL_DISTANCE_MODEL, AL_INVERSE_DISTANCE);
alSourcef(source, AL_REFERENCE_DISTANCE, rolloff->MinDistance/distscale);
alSourcef(source, AL_MAX_DISTANCE, (1000.f+rolloff->MinDistance)/distscale);
rolloffFactor = rolloff->RolloffFactor;
manualGain = false;
gain = 1.f;
}
else if(rolloff->RolloffType == ROLLOFF_Linear && AL.EXT_source_distance_model)
{
alSourcei(source, AL_DISTANCE_MODEL, AL_LINEAR_DISTANCE);
alSourcef(source, AL_REFERENCE_DISTANCE, rolloff->MinDistance/distscale);
alSourcef(source, AL_MAX_DISTANCE, rolloff->MaxDistance/distscale);
rolloffFactor = 1.f;
manualGain = false;
gain = 1.f;
}
}
if(manualGain)
if(rolloff->RolloffType == ROLLOFF_Log)
{
if(AL.EXT_source_distance_model)
alSourcei(source, AL_DISTANCE_MODEL, AL_NONE);
if((chanflags&SNDF_AREA) && rolloff->MinDistance < 32.f)
alSourcef(source, AL_REFERENCE_DISTANCE, 32.f/distscale);
else
alSourcef(source, AL_REFERENCE_DISTANCE, rolloff->MinDistance/distscale);
alSourcei(source, AL_DISTANCE_MODEL, AL_INVERSE_DISTANCE);
alSourcef(source, AL_REFERENCE_DISTANCE, rolloff->MinDistance/distscale);
alSourcef(source, AL_MAX_DISTANCE, (1000.f+rolloff->MinDistance)/distscale);
rolloffFactor = 0.f;
gain = GetRolloff(rolloff, sqrt(dist_sqr));
alSourcef(source, AL_ROLLOFF_FACTOR, rolloff->RolloffFactor);
rolloffFactor = rolloff->RolloffFactor;
manualRolloff = false;
}
alSourcef(source, AL_ROLLOFF_FACTOR, rolloffFactor);
else if(rolloff->RolloffType == ROLLOFF_Linear && AL.EXT_source_distance_model)
{
alSourcei(source, AL_DISTANCE_MODEL, AL_LINEAR_DISTANCE);
alSourcef(source, AL_REFERENCE_DISTANCE, rolloff->MinDistance/distscale);
alSourcef(source, AL_MAX_DISTANCE, rolloff->MaxDistance/distscale);
alSourcef(source, AL_ROLLOFF_FACTOR, 1.f);
manualRolloff = false;
}
if(manualRolloff)
{
// How manual rolloff works:
//
// If a sound is using Custom or Doom style rolloff, or Linear style
// when AL_EXT_source_distance_model is not supported, we have to play
// around a bit to get appropriate distance attenation. What we do is
// calculate the attenuation that should be applied, then given an
// Inverse Distance rolloff model with OpenAL, reverse the calculation
// to get the distance needed for that much attenuation. The Inverse
// Distance calculation is:
//
// Gain = MinDist / (MinDist + RolloffFactor*(Distance - MinDist))
//
// Thus, the reverse is:
//
// Distance = (MinDist/Gain - MinDist)/RolloffFactor + MinDist
//
// This can be simplified by using a MinDist and RolloffFactor of 1,
// which makes it:
//
// Distance = 1.0f/Gain;
//
// The source position is then set that many units away from the
// listener position, and OpenAL takes care of the rest.
if(AL.EXT_source_distance_model)
alSourcei(source, AL_DISTANCE_MODEL, AL_INVERSE_DISTANCE);
alSourcef(source, AL_REFERENCE_DISTANCE, 1.f);
alSourcef(source, AL_MAX_DISTANCE, 100000.f);
alSourcef(source, AL_ROLLOFF_FACTOR, 1.f);
FVector3 dir = pos - listener->position;
if(dir.DoesNotApproximatelyEqual(FVector3(0.f, 0.f, 0.f)))
{
float gain = GetRolloff(rolloff, sqrt(dist_sqr) * distscale);
dir.Resize((gain > 0.00001f) ? 1.f/gain : 100000.f);
}
dir += listener->position;
alSource3f(source, AL_POSITION, dir[0], dir[1], -dir[2]);
}
else
alSource3f(source, AL_POSITION, pos[0], pos[1], -pos[2]);
alSource3f(source, AL_VELOCITY, vel[0], vel[1], -vel[2]);
alSource3f(source, AL_DIRECTION, 0.f, 0.f, 0.f);
alSourcei(source, AL_SOURCE_RELATIVE, AL_FALSE);
alSourcei(source, AL_LOOPING, (chanflags&SNDF_LOOP) ? AL_TRUE : AL_FALSE);
alSourcef(source, AL_MAX_GAIN, SfxVolume);
alSourcef(source, AL_GAIN, SfxVolume * gain);
alSourcef(source, AL_GAIN, SfxVolume);
if(EnvSlot)
{
@ -1271,7 +1287,7 @@ FISoundChannel *OpenALSoundRenderer::StartSound3D(SoundHandle sfx, SoundListener
chan->Rolloff = *rolloff;
chan->DistanceScale = distscale;
chan->DistanceSqr = dist_sqr;
chan->ManualGain = manualGain;
chan->ManualRolloff = manualRolloff;
return chan;
}
@ -1284,8 +1300,6 @@ void OpenALSoundRenderer::ChannelVolume(FISoundChannel *chan, float volume)
alcSuspendContext(Context);
ALuint source = GET_PTRID(chan->SysChannel);
if(chan->ManualGain)
volume *= GetRolloff(&chan->Rolloff, sqrt(chan->DistanceSqr));
alSourcef(source, AL_GAIN, SfxVolume * volume);
}
@ -1411,21 +1425,24 @@ void OpenALSoundRenderer::UpdateSoundParams3D(SoundListener *listener, FISoundCh
alcSuspendContext(Context);
FVector3 dir = pos - listener->position;
chan->DistanceSqr = dir.LengthSquared();
ALuint source = GET_PTRID(chan->SysChannel);
alSource3f(source, AL_POSITION, pos[0], pos[1], -pos[2]);
alSource3f(source, AL_VELOCITY, vel[0], vel[1], -vel[2]);
chan->DistanceSqr = (pos - listener->position).LengthSquared() *
chan->DistanceScale*chan->DistanceScale;
// Not all sources can use the distance models provided by OpenAL.
// For the ones that can't, apply the calculated attenuation as the
// source gain. Positions still handle the panning,
if(chan->ManualGain)
if(chan->ManualRolloff)
{
float gain = GetRolloff(&chan->Rolloff, sqrt(chan->DistanceSqr));
alSourcef(source, AL_GAIN, SfxVolume*gain*((FSoundChan*)chan)->Volume);
}
if(dir.DoesNotApproximatelyEqual(FVector3(0.f, 0.f, 0.f)))
{
float gain = GetRolloff(&chan->Rolloff, sqrt(chan->DistanceSqr) * chan->DistanceScale);
dir.Resize((gain > 0.00001f) ? 1.f/gain : 100000.f);
}
dir += listener->position;
alSource3f(source, AL_POSITION, dir[0], dir[1], -dir[2]);
}
else
alSource3f(source, AL_POSITION, pos[0], pos[1], -pos[2]);
alSource3f(source, AL_VELOCITY, vel[0], vel[1], -vel[2]);
getALError();
}
@ -1581,14 +1598,10 @@ float OpenALSoundRenderer::GetAudibility(FISoundChannel *chan)
ALuint source = GET_PTRID(chan->SysChannel);
ALfloat volume = 0.f;
if(!chan->ManualGain)
volume = SfxVolume * ((FSoundChan*)chan)->Volume *
GetRolloff(&chan->Rolloff, sqrt(chan->DistanceSqr));
else
{
alGetSourcef(source, AL_GAIN, &volume);
getALError();
}
alGetSourcef(source, AL_GAIN, &volume);
getALError();
volume *= GetRolloff(&chan->Rolloff, sqrt(chan->DistanceSqr) * chan->DistanceScale);
return volume;
}