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-rw-r--r--Alc/ALu.c89
1 files changed, 46 insertions, 43 deletions
diff --git a/Alc/ALu.c b/Alc/ALu.c
index 9af14975..ec004294 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -294,7 +294,8 @@ ALvoid CalcNonAttnSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
{
for(c = 0;c < num_channels;c++)
{
- if(chans[c].channel == LFE) /* Special-case LFE */
+ /* Special-case LFE */
+ if(chans[c].channel == LFE)
{
SrcMatrix[c][LFE] += DryGain * ListenerGain;
continue;
@@ -375,20 +376,25 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
for(i = 0;i < MAX_SENDS;i++)
WetGainHF[i] = 1.0f;
- //Get context properties
+ /* Get context/device properties */
DopplerFactor = ALContext->DopplerFactor * ALSource->DopplerFactor;
SpeedOfSound = ALContext->SpeedOfSound * ALContext->DopplerVelocity;
NumSends = Device->NumAuxSends;
Frequency = Device->Frequency;
- //Get listener properties
+ /* Get listener properties */
ListenerGain = ALContext->Listener.Gain;
MetersPerUnit = ALContext->Listener.MetersPerUnit;
ListenerVel[0] = ALContext->Listener.Velocity[0];
ListenerVel[1] = ALContext->Listener.Velocity[1];
ListenerVel[2] = ALContext->Listener.Velocity[2];
+ for(i = 0;i < 4;i++)
+ {
+ for(j = 0;j < 4;j++)
+ Matrix[i][j] = ALContext->Listener.Matrix[i][j];
+ }
- //Get source properties
+ /* Get source properties */
SourceVolume = ALSource->Gain;
MinVolume = ALSource->MinGain;
MaxVolume = ALSource->MaxGain;
@@ -454,13 +460,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
ALSource->Params.Send[i].Slot = Slot;
}
- for(i = 0;i < 4;i++)
- {
- for(j = 0;j < 4;j++)
- Matrix[i][j] = ALContext->Listener.Matrix[i][j];
- }
-
- //1. Translate Listener to origin (convert to head relative)
+ /* Transform source to listener space (convert to head relative) */
if(ALSource->HeadRelative == AL_FALSE)
{
/* Translate position */
@@ -468,16 +468,16 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
Position[1] -= ALContext->Listener.Position[1];
Position[2] -= ALContext->Listener.Position[2];
- /* Transform source vectors into listener space */
+ /* Transform source vectors */
aluMatrixVector(Position, 1.0f, Matrix);
aluMatrixVector(Direction, 0.0f, Matrix);
aluMatrixVector(Velocity, 0.0f, Matrix);
- /* Transform listener velocity into listener space */
+ /* Transform listener velocity */
aluMatrixVector(ListenerVel, 0.0f, Matrix);
}
else
{
- /* Transform listener velocity into listener space */
+ /* Transform listener velocity from world space to listener space */
aluMatrixVector(ListenerVel, 0.0f, Matrix);
/* Offset the source velocity to be relative of the listener velocity */
Velocity[0] += ListenerVel[0];
@@ -491,7 +491,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
aluNormalize(SourceToListener);
aluNormalize(Direction);
- //2. Calculate distance attenuation
+ /* Calculate distance attenuation */
Distance = aluSqrt(aluDotproduct(Position, Position));
ClampedDist = Distance;
@@ -505,7 +505,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
ClampedDist = clampf(ClampedDist, MinDist, MaxDist);
if(MaxDist < MinDist)
break;
- //fall-through
+ /*fall-through*/
case InverseDistance:
if(MinDist > 0.0f)
{
@@ -523,7 +523,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
ClampedDist = clampf(ClampedDist, MinDist, MaxDist);
if(MaxDist < MinDist)
break;
- //fall-through
+ /*fall-through*/
case LinearDistance:
if(MaxDist != MinDist)
{
@@ -541,7 +541,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
ClampedDist = clampf(ClampedDist, MinDist, MaxDist);
if(MaxDist < MinDist)
break;
- //fall-through
+ /*fall-through*/
case ExponentDistance:
if(ClampedDist > 0.0f && MinDist > 0.0f)
{
@@ -556,12 +556,12 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
break;
}
- // Source Gain + Attenuation
+ /* Source Gain + Attenuation */
DryGain = SourceVolume * Attenuation;
for(i = 0;i < NumSends;i++)
WetGain[i] = SourceVolume * RoomAttenuation[i];
- // Distance-based air absorption
+ /* Distance-based air absorption */
if(AirAbsorptionFactor > 0.0f && ClampedDist > MinDist)
{
ALfloat meters = maxf(ClampedDist-MinDist, 0.0f) * MetersPerUnit;
@@ -590,7 +590,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
/* Calculate directional soundcones */
Angle = aluAcos(aluDotproduct(Direction,SourceToListener)) * (180.0f/F_PI);
- if(Angle >= InnerAngle && Angle <= OuterAngle)
+ if(Angle > InnerAngle && Angle <= OuterAngle)
{
ALfloat scale = (Angle-InnerAngle) / (OuterAngle-InnerAngle);
ConeVolume = lerp(1.0f, ALSource->OuterGain, scale);
@@ -621,12 +621,12 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
WetGainHF[i] *= ConeHF;
}
- // Clamp to Min/Max Gain
+ /* Clamp to Min/Max Gain */
DryGain = clampf(DryGain, MinVolume, MaxVolume);
for(i = 0;i < NumSends;i++)
WetGain[i] = clampf(WetGain[i], MinVolume, MaxVolume);
- // Apply filter gains and filters
+ /* Apply gain and frequency filters */
DryGain *= ALSource->DirectGain * ListenerGain;
DryGainHF *= ALSource->DirectGainHF;
for(i = 0;i < NumSends;i++)
@@ -635,7 +635,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
WetGainHF[i] *= ALSource->Send[i].WetGainHF;
}
- // Calculate Velocity
+ /* Calculate velocity-based doppler effect */
if(DopplerFactor > 0.0f)
{
ALfloat VSS, VLS;
@@ -659,6 +659,8 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
ALbuffer *ALBuffer;
if((ALBuffer=BufferListItem->buffer) != NULL)
{
+ /* Calculate fixed-point stepping value, based on the pitch, buffer
+ * frequency, and output frequency. */
ALsizei maxstep = STACK_DATA_SIZE/sizeof(ALfloat) /
ALSource->NumChannels;
maxstep -= ResamplerPadding[Resampler] +
@@ -688,7 +690,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
if(Device->Hrtf)
{
- // Use a binaural HRTF algorithm for stereo headphone playback
+ /* Use a binaural HRTF algorithm for stereo headphone playback */
ALfloat delta, ev = 0.0f, az = 0.0f;
if(Distance > 0.0f)
@@ -698,21 +700,21 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
Position[1] *= invlen;
Position[2] *= invlen;
- // Calculate elevation and azimuth only when the source is not at
- // the listener. This prevents +0 and -0 Z from producing
- // inconsistent panning.
+ /* Calculate elevation and azimuth only when the source is not at
+ * the listener. This prevents +0 and -0 Z from producing
+ * inconsistent panning. */
ev = aluAsin(Position[1]);
az = aluAtan2(Position[0], -Position[2]*ZScale);
}
- // Check to see if the HRIR is already moving.
+ /* Check to see if the HRIR is already moving. */
if(ALSource->HrtfMoving)
{
- // Calculate the normalized HRTF transition factor (delta).
+ /* Calculate the normalized HRTF transition factor (delta). */
delta = CalcHrtfDelta(ALSource->Params.HrtfGain, DryGain,
ALSource->Params.HrtfDir, Position);
- // If the delta is large enough, get the moving HRIR target
- // coefficients, target delays, steppping values, and counter.
+ /* If the delta is large enough, get the moving HRIR target
+ * coefficients, target delays, steppping values, and counter. */
if(delta > 0.001f)
{
ALSource->HrtfCounter = GetMovingHrtfCoeffs(Device->Hrtf,
@@ -730,7 +732,7 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
}
else
{
- // Get the initial (static) HRIR coefficients and delays.
+ /* Get the initial (static) HRIR coefficients and delays. */
GetLerpedHrtfCoeffs(Device->Hrtf, ev, az, DryGain,
ALSource->Params.HrtfCoeffs[0],
ALSource->Params.HrtfDelay[0]);
@@ -743,12 +745,14 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
}
else
{
- // Use energy-preserving panning algorithm for multi-speaker playback
+ /* Use a lookup table for panning multi-speaker playback. */
ALfloat DirGain, AmbientGain;
const ALfloat *ChannelGain;
ALfloat length;
ALint pos;
+ /* Normalize the length based on the source's min distance. Sources
+ * closer than this will not pan as much. */
length = maxf(Distance, MinDist);
if(length > 0.0f)
{
@@ -761,15 +765,14 @@ ALvoid CalcSourceParams(ALsource *ALSource, const ALCcontext *ALContext)
pos = aluCart2LUTpos(-Position[2]*ZScale, Position[0]);
ChannelGain = Device->PanningLUT[pos];
+ /* Adjustment for partial panning. Not the greatest, but simple
+ * enough. */
DirGain = aluSqrt(Position[0]*Position[0] + Position[2]*Position[2]);
- // elevation adjustment for directional gain. this sucks, but
- // has low complexity
AmbientGain = aluSqrt(1.0f/Device->NumChan);
for(i = 0;i < MAXCHANNELS;i++)
{
- ALuint i2;
- for(i2 = 0;i2 < MAXCHANNELS;i2++)
- ALSource->Params.DryGains[i][i2] = 0.0f;
+ for(j = 0;j < MAXCHANNELS;j++)
+ ALSource->Params.DryGains[i][j] = 0.0f;
}
for(i = 0;i < (ALint)Device->NumChan;i++)
{
@@ -931,10 +934,7 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
while(size > 0)
{
- /* Setup variables */
SamplesToDo = minu(size, BUFFERSIZE);
-
- /* Clear mixing buffer */
memset(device->DryBuffer, 0, SamplesToDo*MAXCHANNELS*sizeof(ALfloat));
LockDevice(device);
@@ -947,6 +947,7 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
if(!DeferUpdates)
UpdateSources = ExchangeInt(&ctx->UpdateSources, AL_FALSE);
+ /* source processing */
src = ctx->ActiveSources;
src_end = src + ctx->ActiveSourceCount;
while(src != src_end)
@@ -1016,7 +1017,9 @@ ALvoid aluMixData(ALCdevice *device, ALvoid *buffer, ALsizei size)
}
UnlockDevice(device);
- //Post processing loop
+ /* Click-removal. Could do better; this only really handles immediate
+ * changes between updates where a predictive sample could be
+ * generated. Delays caused by effects and HRTF aren't caught. */
if(device->FmtChans == DevFmtMono)
{
for(i = 0;i < SamplesToDo;i++)
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-12 12:04:41 +0000