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-rw-r--r--Alc/effects/reverb.c99
1 files changed, 39 insertions, 60 deletions
diff --git a/Alc/effects/reverb.c b/Alc/effects/reverb.c
index 7dfa37d1..d8dd14f3 100644
--- a/Alc/effects/reverb.c
+++ b/Alc/effects/reverb.c
@@ -90,15 +90,11 @@ typedef struct ALreverbState {
/* Core delay line (early reflections and late reverb tap from this). */
DelayLine Delay;
- /* The tap points for the initial delay. First tap goes to early
+ /* The tap points for the initial delay. First set go to early
* reflections, second to late reverb.
*/
- ALuint DelayTap[2];
- /* There are actually 4 decorrelator taps, but the first occurs at the late
- * reverb tap.
- */
- ALuint EarlyDecoTap[3];
- ALuint LateDecoTap[3];
+ ALuint EarlyDelayTap[4];
+ ALuint LateDelayTap[4];
struct {
// Early reflections are done with 4 delay lines.
@@ -221,14 +217,10 @@ static void ALreverbState_Construct(ALreverbState *state)
state->Delay.Mask = 0;
state->Delay.Line = NULL;
- state->DelayTap[0] = 0;
- state->DelayTap[1] = 0;
- state->EarlyDecoTap[0] = 0;
- state->EarlyDecoTap[1] = 0;
- state->EarlyDecoTap[2] = 0;
- state->LateDecoTap[0] = 0;
- state->LateDecoTap[1] = 0;
- state->LateDecoTap[2] = 0;
+ for(index = 0;index < 4;index++)
+ state->EarlyDelayTap[index] = 0;
+ for(index = 0;index < 4;index++)
+ state->LateDelayTap[index] = 0;
for(index = 0;index < 4;index++)
{
@@ -330,7 +322,7 @@ static const ALfloat ECHO_ALLPASS_LENGTH = 0.0133f;
/* Input into the early reflections and late reverb are decorrelated between
* four channels. Their timings are dependent on a fraction and multiplier. See
- * the UpdateDecorrelator() routine for the calculations involved.
+ * the UpdateDelayLine() routine for the calculations involved.
*/
static const ALfloat DECO_FRACTION = 0.15f;
static const ALfloat DECO_MULTIPLIER = 2.0f;
@@ -669,12 +661,27 @@ static ALvoid UpdateModulator(ALfloat modTime, ALfloat modDepth, ALuint frequenc
2.0f * frequency;
}
-// Update the offsets for the initial effect delay line.
-static ALvoid UpdateDelayLine(ALfloat earlyDelay, ALfloat lateDelay, ALuint frequency, ALreverbState *State)
+// Update the offsets for the main effect delay line.
+static ALvoid UpdateDelayLine(ALfloat earlyDelay, ALfloat lateDelay, ALfloat density, ALuint frequency, ALreverbState *State)
{
- // Calculate the initial delay taps.
- State->DelayTap[0] = fastf2u(earlyDelay * frequency);
- State->DelayTap[1] = fastf2u((earlyDelay + lateDelay) * frequency);
+ ALfloat length;
+ ALuint i;
+
+ State->EarlyDelayTap[0] = fastf2u(earlyDelay * frequency);
+ for(i = 1;i < 4;i++)
+ {
+ length = (DECO_FRACTION * powf(DECO_MULTIPLIER, (ALfloat)i-1.0f)) *
+ EARLY_LINE_LENGTH[0];
+ State->EarlyDelayTap[i] = fastf2u(length * frequency) + State->EarlyDelayTap[0];
+ }
+
+ State->LateDelayTap[0] = fastf2u((earlyDelay + lateDelay) * frequency);
+ for(i = 1;i < 4;i++)
+ {
+ length = (DECO_FRACTION * powf(DECO_MULTIPLIER, (ALfloat)i-1.0f)) *
+ LATE_LINE_LENGTH[0] * (1.0f + (density * LATE_LINE_MULTIPLIER));
+ State->LateDelayTap[i] = fastf2u(length * frequency) + State->LateDelayTap[0];
+ }
}
// Update the early reflections mix and line coefficients.
@@ -690,31 +697,6 @@ static ALvoid UpdateEarlyLines(ALfloat lateDelay, ALreverbState *State)
lateDelay);
}
-// Update the offsets for the decorrelator line.
-static ALvoid UpdateDecorrelator(ALfloat density, ALuint frequency, ALreverbState *State)
-{
- ALuint index;
- ALfloat length;
-
- /* The early reflections and late reverb inputs are decorrelated to provide
- * time-varying reflections, smooth out the reverb tail, and reduce harsh
- * echos. The first tap occurs immediately, while the remaining taps are
- * delayed by multiples of a fraction of the smallest cyclical delay time.
- *
- * offset[index] = (FRACTION (MULTIPLIER^index)) smallest_delay
- */
- for(index = 0;index < 3;index++)
- {
- length = (DECO_FRACTION * powf(DECO_MULTIPLIER, (ALfloat)index)) *
- EARLY_LINE_LENGTH[0];
- State->EarlyDecoTap[index] = fastf2u(length * frequency) + State->DelayTap[0];
-
- length = (DECO_FRACTION * powf(DECO_MULTIPLIER, (ALfloat)index)) *
- LATE_LINE_LENGTH[0] * (1.0f + (density * LATE_LINE_MULTIPLIER));
- State->LateDecoTap[index] = fastf2u(length * frequency) + State->DelayTap[1];
- }
-}
-
// Update the late reverb mix, line lengths, and line coefficients.
static ALvoid UpdateLateLines(ALfloat xMix, ALfloat density, ALfloat decayTime, ALfloat diffusion, ALfloat echoDepth, ALfloat hfRatio, ALfloat cw, ALuint frequency, ALreverbState *State)
{
@@ -975,12 +957,9 @@ static ALvoid ALreverbState_update(ALreverbState *State, const ALCdevice *Device
UpdateModulator(props->Reverb.ModulationTime, props->Reverb.ModulationDepth,
frequency, State);
- // Update the initial effect delay.
+ // Update the main effect delay.
UpdateDelayLine(props->Reverb.ReflectionsDelay, props->Reverb.LateReverbDelay,
- frequency, State);
-
- // Update the decorrelator.
- UpdateDecorrelator(props->Reverb.Density, frequency, State);
+ props->Reverb.Density, frequency, State);
// Update the early lines.
UpdateEarlyLines(props->Reverb.LateReverbDelay, State);
@@ -1112,10 +1091,10 @@ static ALvoid EarlyReflection(ALreverbState *State, ALuint todo, ALfloat (*restr
ALuint offset = State->Offset+i;
/* Obtain the first reflection samples from the main delay line. */
- f[0] = DelayLineOut(&State->Delay, (offset-State->DelayTap[0])*4 + 0);
- f[1] = DelayLineOut(&State->Delay, (offset-State->EarlyDecoTap[0])*4 + 1);
- f[2] = DelayLineOut(&State->Delay, (offset-State->EarlyDecoTap[1])*4 + 2);
- f[3] = DelayLineOut(&State->Delay, (offset-State->EarlyDecoTap[2])*4 + 3);
+ f[0] = DelayLineOut(&State->Delay, (offset-State->EarlyDelayTap[0])*4 + 0);
+ f[1] = DelayLineOut(&State->Delay, (offset-State->EarlyDelayTap[1])*4 + 1);
+ f[2] = DelayLineOut(&State->Delay, (offset-State->EarlyDelayTap[2])*4 + 2);
+ f[3] = DelayLineOut(&State->Delay, (offset-State->EarlyDelayTap[3])*4 + 3);
/* The following uses a lossless scattering junction from waveguide
* theory. It actually amounts to a householder mixing matrix, which
@@ -1201,10 +1180,10 @@ static ALvoid LateReverb(ALreverbState *State, ALuint todo, ALfloat (*restrict o
for(i = 0;i < tmp_todo;i++)
{
/* Obtain four decorrelated input samples. */
- f[0] = DelayLineOut(&State->Delay, (offset-State->DelayTap[1])*4 + 0) * State->Late.DensityGain;
- f[1] = DelayLineOut(&State->Delay, (offset-State->LateDecoTap[0])*4 + 1) * State->Late.DensityGain;
- f[2] = DelayLineOut(&State->Delay, (offset-State->LateDecoTap[1])*4 + 2) * State->Late.DensityGain;
- f[3] = DelayLineOut(&State->Delay, (offset-State->LateDecoTap[2])*4 + 3) * State->Late.DensityGain;
+ f[0] = DelayLineOut(&State->Delay, (offset-State->LateDelayTap[0])*4 + 0) * State->Late.DensityGain;
+ f[1] = DelayLineOut(&State->Delay, (offset-State->LateDelayTap[1])*4 + 1) * State->Late.DensityGain;
+ f[2] = DelayLineOut(&State->Delay, (offset-State->LateDelayTap[2])*4 + 2) * State->Late.DensityGain;
+ f[3] = DelayLineOut(&State->Delay, (offset-State->LateDelayTap[3])*4 + 3) * State->Late.DensityGain;
/* Add the decayed results of the cyclical delay lines, then pass
* the results through the low-pass filters.
@@ -1313,7 +1292,7 @@ static ALvoid EAXEcho(ALreverbState *State, ALuint todo, ALfloat (*restrict late
// Mix the energy-attenuated input with the output and pass it through
// the echo low-pass filter.
- feed += DelayLineOut(&State->Delay, (offset-State->DelayTap[1])*4 + c) *
+ feed += DelayLineOut(&State->Delay, (offset-State->LateDelayTap[0])*4 + c) *
State->Echo.DensityGain;
feed = lerp(feed, State->Echo.LpSample[c], State->Echo.LpCoeff);
State->Echo.LpSample[c] = feed;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 18:45:31 +0000