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-rw-r--r--Alc/ALu.c87
-rw-r--r--Alc/lpfilter.c432
-rw-r--r--CMakeLists.txt1
-rw-r--r--OpenAL32/Include/alFilter.h6
-rw-r--r--OpenAL32/Include/alSource.h3
-rw-r--r--OpenAL32/alAuxEffectSlot.c2
-rw-r--r--OpenAL32/alSource.c4
7 files changed, 43 insertions, 492 deletions
diff --git a/Alc/ALu.c b/Alc/ALu.c
index 9baf6cee..3b8be4a2 100644
--- a/Alc/ALu.c
+++ b/Alc/ALu.c
@@ -157,31 +157,18 @@ __inline ALuint aluChannelsFromFormat(ALenum format)
static __inline ALfloat lpFilter(FILTER *iir, ALfloat input)
{
- float *hist1_ptr,*hist2_ptr,*coef_ptr;
- ALfloat output,new_hist,history1,history2;
-
- coef_ptr = iir->coef; /* coefficient pointer */
-
- hist1_ptr = iir->history; /* first history */
- hist2_ptr = hist1_ptr + 1; /* next history */
-
- /* 1st number of coefficients array is overall input scale factor,
- * or filter gain */
- output = input * (*coef_ptr++);
-
- history1 = *hist1_ptr; /* history values */
- history2 = *hist2_ptr;
-
- output = output - history1 * (*coef_ptr++);
- new_hist = output - history2 * (*coef_ptr++); /* poles */
-
- output = new_hist + history1 * (*coef_ptr++);
- output = output + history2 * (*coef_ptr++); /* zeros */
-
- *hist2_ptr++ = *hist1_ptr;
- *hist1_ptr++ = new_hist;
- hist1_ptr++;
- hist2_ptr++;
+ ALfloat *history = iir->history;
+ ALfloat a = iir->coeff;
+ ALfloat output = input;
+
+ output = output + (history[0]-output)*a;
+ history[0] = output;
+ output = output + (history[1]-output)*a;
+ history[1] = output;
+ output = output + (history[2]-output)*a;
+ history[2] = output;
+ output = output + (history[3]-output)*a;
+ history[3] = output;
return output;
}
@@ -234,10 +221,6 @@ static __inline ALvoid aluMatrixVector(ALfloat *vector,ALfloat matrix[3][3])
memcpy(vector, result, sizeof(result));
}
-static __inline ALfloat aluComputeSample(ALfloat GainHF, ALfloat sample, ALfloat LowSample)
-{
- return LowSample + ((sample - LowSample) * GainHF);
-}
static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
ALenum isMono, ALenum OutputFormat,
@@ -258,6 +241,7 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
ALfloat RoomRolloff;
ALfloat DryGainHF = 1.0f;
ALfloat WetGainHF = 1.0f;
+ ALfloat cw, a, g;
//Get context properties
DopplerFactor = ALContext->DopplerFactor * ALSource->DopplerFactor;
@@ -604,6 +588,25 @@ static ALvoid CalcSourceParams(ALCcontext *ALContext, ALsource *ALSource,
break;
}
+ // Update filter coefficients. Calculations based on the I3DL2 spec.
+ cw = cos(2.0f*3.141592654f * LOWPASSFREQCUTOFF / ALContext->Frequency);
+ // We use four chained one-pole filters, so we need to take the fourth
+ // root of the squared gain, which is the same as the square root of
+ // the base gain.
+ // Be careful with gains < 0.0001, as that causes the coefficient to
+ // head towards 1, which will flatten the signal
+ g = aluSqrt(__max(DryGainHF, 0.0001f));
+ a = 0.0f;
+ if(g < 0.9999f) // 1-epsilon
+ a = (1 - g*cw - aluSqrt(2*g*(1-cw) - g*g*(1 - cw*cw))) / (1 - g);
+ ALSource->iirFilter.coeff = a;
+
+ g = aluSqrt(__max(WetGainHF, 0.0001f));
+ a = 0.0f;
+ if(g < 0.9999f) // 1-epsilon
+ a = (1 - g*cw - aluSqrt(2*g*(1-cw) - g*g*(1 - cw*cw))) / (1 - g);
+ ALSource->Send[0].iirFilter.coeff = a;
+
*drygainhf = DryGainHF;
*wetgainhf = WetGainHF;
}
@@ -648,8 +651,6 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
ALuint rampLength;
ALfloat dryGainStep[OUTPUTCHANNELS];
ALfloat wetGainStep[OUTPUTCHANNELS];
- ALfloat dryGainHFStep;
- ALfloat wetGainHFStep;
ALuint BlockAlign,BufferSize;
ALuint DataSize=0,DataPosInt=0,DataPosFrac=0;
ALuint Channels,Frequency,ulExtraSamples;
@@ -667,7 +668,7 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
ALbufferlistitem *BufferListItem;
ALuint loop;
ALint64 DataSize64,DataPos64;
- FILTER *Filter;
+ FILTER *DryFilter, *WetFilter;
int fpuState;
SuspendContext(ALContext);
@@ -742,7 +743,8 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
//Get source info
DataPosInt = ALSource->position;
DataPosFrac = ALSource->position_fraction;
- Filter = &ALSource->iirFilter;
+ DryFilter = &ALSource->iirFilter;
+ WetFilter = &ALSource->Send[0].iirFilter;
DrySend = ALSource->DryGains;
WetSend = ALSource->WetGains;
@@ -752,10 +754,6 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
dryGainStep[i] = (newDrySend[i]-DrySend[i]) / rampLength;
wetGainStep[i] = (newWetSend[i]-WetSend[i]) / rampLength;
}
- dryGainHFStep = (DryGainHF-ALSource->DryGainHF) / rampLength;
- wetGainHFStep = (WetGainHF-ALSource->WetGainHF) / rampLength;
- DryGainHF = ALSource->DryGainHF;
- WetGainHF = ALSource->WetGainHF;
//Compute 18.14 fixed point step
increment = (ALint)(Pitch*(ALfloat)(1L<<FRACTIONBITS));
@@ -815,19 +813,16 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
DrySend[i] += dryGainStep[i];
WetSend[i] += wetGainStep[i];
}
- DryGainHF += dryGainHFStep;
- WetGainHF += wetGainHFStep;
if(Channels==1)
{
- ALfloat sample, lowsamp, outsamp;
+ ALfloat sample, outsamp;
//First order interpolator
sample = (Data[k]*((1<<FRACTIONBITS)-fraction) +
Data[k+1]*fraction) >> FRACTIONBITS;
- lowsamp = lpFilter(Filter, sample);
//Direct path final mix buffer and panning
- outsamp = aluComputeSample(DryGainHF, sample, lowsamp);
+ outsamp = lpFilter(DryFilter, sample);
DryBuffer[j][FRONT_LEFT] += outsamp*DrySend[FRONT_LEFT];
DryBuffer[j][FRONT_RIGHT] += outsamp*DrySend[FRONT_RIGHT];
DryBuffer[j][SIDE_LEFT] += outsamp*DrySend[SIDE_LEFT];
@@ -835,7 +830,7 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
DryBuffer[j][BACK_LEFT] += outsamp*DrySend[BACK_LEFT];
DryBuffer[j][BACK_RIGHT] += outsamp*DrySend[BACK_RIGHT];
//Room path final mix buffer and panning
- outsamp = aluComputeSample(WetGainHF, sample, lowsamp);
+ outsamp = lpFilter(WetFilter, sample);
WetBuffer[j][FRONT_LEFT] += outsamp*WetSend[FRONT_LEFT];
WetBuffer[j][FRONT_RIGHT] += outsamp*WetSend[FRONT_RIGHT];
WetBuffer[j][SIDE_LEFT] += outsamp*WetSend[SIDE_LEFT];
@@ -923,8 +918,6 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
//Update source info
ALSource->position = DataPosInt;
ALSource->position_fraction = DataPosFrac;
- ALSource->DryGainHF = DryGainHF;
- ALSource->WetGainHF = WetGainHF;
}
//Handle looping sources
@@ -1015,7 +1008,7 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
ALfloat LateReverbGain = ALEffectSlot->effect.Reverb.LateReverbGain;
ALfloat sample, lowsample;
- Filter = &ALEffectSlot->iirFilter;
+ WetFilter = &ALEffectSlot->iirFilter;
for(i = 0;i < SamplesToDo;i++)
{
sample = WetBuffer[i][FRONT_LEFT] +WetBuffer[i][SIDE_LEFT] +WetBuffer[i][BACK_LEFT];
@@ -1027,7 +1020,7 @@ ALvoid aluMixData(ALCcontext *ALContext,ALvoid *buffer,ALsizei size,ALenum forma
DelayBuffer[LatePos] *= LateReverbGain;
Pos = (Pos+1) % Length;
- lowsample = lpFilter(Filter, DelayBuffer[Pos]);
+ lowsample = lpFilter(WetFilter, DelayBuffer[Pos]);
lowsample += (DelayBuffer[Pos]-lowsample) * DecayHFRatio;
DelayBuffer[LatePos] += lowsample * DecayGain;
diff --git a/Alc/lpfilter.c b/Alc/lpfilter.c
deleted file mode 100644
index 98019e2e..00000000
--- a/Alc/lpfilter.c
+++ /dev/null
@@ -1,432 +0,0 @@
-/* ----------------- file filterIIR00.c begin ----------------- */
-/*
-Resonant low pass filter source code.
-By [email protected] (Zxform)
-*/
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <math.h>
-
-#include "alMain.h"
-#include "alFilter.h"
-
-
-static void szxform(
- double *a0, double *a1, double *a2, /* numerator coefficients */
- double *b0, double *b1, double *b2, /* denominator coefficients */
- double fc, /* Filter cutoff frequency */
- double fs, /* sampling rate */
- double *k, /* overall gain factor */
- float *coef); /* pointer to 4 iir coefficients */
-
-/*
- * --------------------------------------------------------------------
- *
- * lpFilter - Perform IIR filtering sample by sample on floats
- *
- * Implements cascaded direct form II second order sections.
- * Requires FILTER structure for history and coefficients.
- * The size of the history array is 2*FILTER_SECTIONS.
- * The size of the coefficient array is 4*FILTER_SECTIONS + 1 because
- * the first coefficient is the overall scale factor for the filter.
- * Returns one output sample for each input sample.
- *
- * float lpFilter(FILTER *iir,float input)
- *
- * FILTER *iir pointer to FILTER structure
- * float input new float input sample
- *
- * Returns float value giving the current output.
- * --------------------------------------------------------------------
- */
-
-/*** moved to ALu.c ***/
-
-/*
- * --------------------------------------------------------------------
- *
- * InitLowPassFilter()
- *
- * Initialize filter coefficients.
- * We create a 2nd order filter (12 db/oct rolloff), consisting
- * of one second order section.
- * --------------------------------------------------------------------
- */
-int InitLowPassFilter(ALCcontext *Context, FILTER *iir)
-{
- float *coef;
- double fs, fc; /* Sampling frequency, cutoff frequency */
- double Q; /* Resonance > 1.0 < 1000 */
- double a0, a1, a2, b0, b1, b2;
- double k; /* overall gain factor */
- struct {
- double a0, a1, a2; /* numerator coefficients */
- double b0, b1, b2; /* denominator coefficients */
- } ProtoCoef; /* Filter prototype coefficients,
- 1 for each filter section */
-
-
- /*
- * Setup filter s-domain coefficients
- */
- /* Section 1 */
- ProtoCoef.a0 = 1.0;
- ProtoCoef.a1 = 0;
- ProtoCoef.a2 = 0;
- ProtoCoef.b0 = 1.0;
- ProtoCoef.b1 = 1.4142;
- ProtoCoef.b2 = 1.0;
-
- /* Clear the coefficient and history arrays */
- memset(iir->coef, 0, sizeof(iir->coef));
- memset(iir->history, 0, sizeof(iir->history));
-
- k = 1.0; /* Set overall filter gain */
- coef = iir->coef + 1; /* Skip k, or gain */
-
- Q = 1; /* Resonance */
- fc = LOWPASSFREQCUTOFF; /* Filter cutoff (Hz) */
- fs = Context->Frequency; /* Sampling frequency (Hz) */
-
- /*
- * Compute z-domain coefficients for each biquad section
- * for new Cutoff Frequency and Resonance
- */
- a0 = ProtoCoef.a0;
- a1 = ProtoCoef.a1;
- a2 = ProtoCoef.a2;
-
- b0 = ProtoCoef.b0;
- b1 = ProtoCoef.b1 / Q; /* Divide by resonance or Q */
- b2 = ProtoCoef.b2;
- szxform(&a0, &a1, &a2, &b0, &b1, &b2, fc, fs, &k, coef);
-
- /* Update overall filter gain in coef array */
- iir->coef[0] = k;
-
- return 0;
-}
-/* ----------------- file filterIIR00.c end ----------------- */
-
-
-/* ----------------- file bilinear.c begin ----------------- */
-/*
- * ----------------------------------------------------------
- * bilinear.c
- *
- * Perform bilinear transformation on s-domain coefficients
- * of 2nd order biquad section.
- * First design an analog filter and use s-domain coefficients
- * as input to szxform() to convert them to z-domain.
- *
- * Here's the butterworth polinomials for 2nd, 4th and 6th order sections.
- * When we construct a 12 db/oct filter, we take a 2nd order
- * section and compute the coefficients.
- *
- * n Polinomials
- * --------------------------------------------------------------------
- * 2 s^2 + 1.4142s +1
- * 4 (s^2 + 0.765367s + 1) (s^2 + 1.847759s + 1)
- * 6 (s^2 + 0.5176387s + 1) (s^2 + 1.414214 + 1) (s^2 + 1.931852s + 1)
- *
- * Where n is a filter order.
- * For n=2, or one second order section, we have following equasion:
- *
- * (1 / (s^2 + (1/Q) * 1.4142s + 1))
- *
- * Where Q is filter quality factor in the range of
- * 1 to 1000. The overall filter Q is a product of all
- * 2nd order stages. For example, the 6th order filter
- * (3 stages, or biquads) with individual Q of 2 will
- * have filter Q = 2 * 2 * 2 = 8.
- *
- * The nominator part is just 1.
- * The denominator coefficients for stage 1 of filter are:
- * b2 = 1; b1 = 1.4142; b0 = 1;
- * numerator is
- * a2 = 0; a1 = 0; a0 = 1;
- *
- * These coefficients are used directly by the szxform()
- * and bilinear() functions. For all stages the numerator
- * is the same and the only thing that is different between
- * different stages is 1st order coefficient. The rest of
- * coefficients are the same for any stage and equal to 1.
- *
- * Any filter could be constructed using this approach.
- *
- * References:
- * Van Valkenburg, "Analog Filter Design"
- * Oxford University Press 1982
- * ISBN 0-19-510734-9
- *
- * C Language Algorithms for Digital Signal Processing
- * Paul Embree, Bruce Kimble
- * Prentice Hall, 1991
- * ISBN 0-13-133406-9
- *
- * Digital Filter Designer's Handbook
- * With C++ Algorithms
- * Britton Rorabaugh
- * McGraw Hill, 1997
- * ISBN 0-07-053806-9
- * ----------------------------------------------------------
- */
-
-static void prewarp(double *a0, double *a1, double *a2, double fc, double fs);
-static void bilinear(
- double a0, double a1, double a2, /* numerator coefficients */
- double b0, double b1, double b2, /* denominator coefficients */
- double *k, /* overall gain factor */
- double fs, /* sampling rate */
- float *coef); /* pointer to 4 iir coefficients */
-
-
-/*
- * ----------------------------------------------------------
- * Pre-warp the coefficients of a numerator or denominator.
- * Note that a0 is assumed to be 1, so there is no wrapping
- * of it.
- * ----------------------------------------------------------
- */
-static void prewarp(
- double *a0, double *a1, double *a2,
- double fc, double fs)
-{
- static const double pi = 3.141592653589793238;
-
- double wp = 2.0 * fs * tan(pi * fc / fs);
-
- *a2 = (*a2) / (wp * wp);
- *a1 = (*a1) / wp;
- (void)a0;
-}
-
-
-/*
- * ----------------------------------------------------------
- * bilinear()
- *
- * Transform the numerator and denominator coefficients
- * of s-domain biquad section into corresponding
- * z-domain coefficients.
- *
- * Store the 4 IIR coefficients in array pointed by coef
- * in following order:
- * beta1, beta2 (denominator)
- * alpha1, alpha2 (numerator)
- *
- * Arguments:
- * a0-a2 - s-domain numerator coefficients
- * b0-b2 - s-domain denominator coefficients
- * k - filter gain factor. initially set to 1
- * and modified by each biquad section in such
- * a way, as to make it the coefficient by
- * which to multiply the overall filter gain
- * in order to achieve a desired overall filter gain,
- * specified in initial value of k.
- * fs - sampling rate (Hz)
- * coef - array of z-domain coefficients to be filled in.
- *
- * Return:
- * On return, set coef z-domain coefficients
- * ----------------------------------------------------------
- */
-static void bilinear(
- double a0, double a1, double a2, /* numerator coefficients */
- double b0, double b1, double b2, /* denominator coefficients */
- double *k, /* overall gain factor */
- double fs, /* sampling rate */
- float *coef /* pointer to 4 iir coefficients */
-)
-{
- double ad, bd;
-
- /* alpha (Numerator in s-domain) */
- ad = 4. * a2 * fs * fs + 2. * a1 * fs + a0;
- /* beta (Denominator in s-domain) */
- bd = 4. * b2 * fs * fs + 2. * b1* fs + b0;
-
- /* update gain constant for this section */
- *k *= ad/bd;
-
- /* Denominator */
- *coef++ = (2.*b0 - 8.*b2*fs*fs) / bd; /* beta1 */
- *coef++ = (4.*b2*fs*fs - 2.*b1*fs + b0) / bd; /* beta2 */
-
- /* Nominator */
- *coef++ = (2.*a0 - 8.*a2*fs*fs) / ad; /* alpha1 */
- *coef = (4.*a2*fs*fs - 2.*a1*fs + a0) / ad; /* alpha2 */
-}
-
-
-/*
- * ----------------------------------------------------------
- * Transform from s to z domain using bilinear transform
- * with prewarp.
- *
- * Arguments:
- * For argument description look at bilinear()
- *
- * coef - pointer to array of floating point coefficients,
- * corresponding to output of bilinear transofrm
- * (z domain).
- *
- * Note: frequencies are in Hz.
- * ----------------------------------------------------------
- */
-static void szxform(
- double *a0, double *a1, double *a2, /* numerator coefficients */
- double *b0, double *b1, double *b2, /* denominator coefficients */
- double fc, /* Filter cutoff frequency */
- double fs, /* sampling rate */
- double *k, /* overall gain factor */
- float *coef) /* pointer to 4 iir coefficients */
-{
- /* Calculate a1 and a2 and overwrite the original values */
- prewarp(a0, a1, a2, fc, fs);
- prewarp(b0, b1, b2, fc, fs);
- bilinear(*a0, *a1, *a2, *b0, *b1, *b2, k, fs, coef);
-}
-
-
-/* ----------------- file bilinear.c end ----------------- */
-
-/* ----------------- file filter.txt begin -----------------
-How to construct a kewl low pass resonant filter?
-
-Lets assume we want to create a filter for analog synth.
-The filter rolloff is 12 db/oct, which corresponds to 2nd
-order filter. Filter of first order is equivalent to RC circuit
-and has max rolloff of 6 db/oct.
-
-We will use classical Butterworth IIR filter design, as it
-exactly corresponds to our requirements.
-
-Each 2nd order section is a 2nd order filter, which has 12 db/oct
-rolloff. So, we only need one section
-
-To compute those sections, we use standard Butterworth polinomials,
-or so called s-domain representation and convert it into z-domain,
-or digital domain. The reason we need to do this is because
-the filter theory exists for analog filters for a long time
-and there exist no theory of working in digital domain directly.
-So the common practice is to take standard analog filter design
-and use so called bilinear transform to convert the butterworth
-equasion coefficients into z-domain.
-
-Once we compute the z-domain coefficients, we can use them in
-a very simple transfer function, such as iir_filter() in our
-C source code, in order to perform the filtering function.
-The filter itself is the simpliest thing in the world.
-The most complicated thing is computing the coefficients
-for z-domain.
-
-Ok, lets look at butterworth polynomials, arranged as a series
-of 2nd order sections:
-
- * Note: n is filter order.
- *
- * n Polynomials
- * --------------------------------------------------------------------
- * 2 s^2 + 1.4142s +1
- * 4 (s^2 + 0.765367s + 1) * (s^2 + 1.847759s + 1)
- * 6 (s^2 + 0.5176387s + 1) * (s^2 + 1.414214 + 1) * (s^2 + 1.931852s + 1)
- *
- * For n=2 we have following equasion for the filter transfer function:
- *
- * 1
- * T(s) = -------------------------
- * s^2 + (1/Q) * 1.4142s + 1
- *
-
-The filter consists of one 2nd order section since highest s power is 2.
-Now we can take the coefficients, or the numbers by which s is multiplied
-and plug them into a standard formula to be used by bilinear transform.
-
-Our standard form for each 2nd order secion is:
-
- a2 * s^2 + a1 * s + a0
-H(s) = ----------------------
- b2 * s^2 + b1 * s + b0
-
-Note that butterworth nominator is 1 for all filter sections,
-which means s^2 = 0 and s^1 = 0
-
-Lets convert standard butterworth polinomials into this form:
-
- 0 + 0 + 1
-------------------------
-1 + ((1/Q) * 1.4142) + 1
-
-Section 1:
-a2 = 0; a1 = 0; a0 = 1;
-b2 = 1; b1 = 1.4142; b0 = 1;
-
-That Q is filter quality factor or resonance, in the range of
-1 to 1000. The overall filter Q is a product of all 2nd order stages.
-For example, the 6th order filter (3 stages, or biquads)
-with individual Q of 2 will have filter Q = 2 * 2 * 2 = 8.
-
-These a and b coefficients are used directly by the szxform()
-and bilinear() functions.
-
-The transfer function for z-domain is:
-
- 1 + alpha1 * z^(-1) + alpha2 * z^(-2)
-H(z) = -------------------------------------
- 1 + beta1 * z^(-1) + beta2 * z^(-2)
-
-When you need to change the filter frequency cutoff or resonance,
-or Q, you call the szxform() function with proper a and b
-coefficients and the new filter cutoff frequency or resonance.
-You also need to supply the sampling rate and filter gain you want
-to achive. For our purposes the gain = 1.
-
-We call szxform() function 1 time becase we have 1 filter section.
-Each call provides different coefficients.
-
-The gain argument to szxform() is a pointer to desired filter
-gain variable.
-
-double k = 1.0; // overall gain factor
-
-Upon return from each call, the k argument will be set to a value,
-by which to multiply our actual signal in order for the gain
-to be one. On following calls to szxform() we provide k that was
-changed by the previous section. During actual audio filtering
-function iir_filter() will use this k
-
-Summary:
-
-Our filter is pretty close to ideal in terms of all relevant
-parameters and filter stability even with extremely large values
-of resonance. This filter design has been verified under all
-variations of parameters and it all appears to work as advertized.
-
-Good luck with it.
-If you ever make a directX wrapper for it, post it to comp.dsp.
-
-
- *
- * ----------------------------------------------------------
- *References:
- *Van Valkenburg, "Analog Filter Design"
- *Oxford University Press 1982
- *ISBN 0-19-510734-9
- *
- *C Language Algorithms for Digital Signal Processing
- *Paul Embree, Bruce Kimble
- *Prentice Hall, 1991
- *ISBN 0-13-133406-9
- *
- *Digital Filter Designer's Handbook
- *With C++ Algorithms
- *Britton Rorabaugh
- *McGraw Hill, 1997
- *ISBN 0-07-053806-9
- * ----------------------------------------------------------
-
-
-
-// ----------------- file filter.txt end ----------------- */
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9d5f2e59..1883ee81 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -231,7 +231,6 @@ SET(ALC_OBJS Alc/ALc.c
Alc/alcRing.c
Alc/alcThread.c
Alc/bs2b.c
- Alc/lpfilter.c
Alc/wave.c
)
diff --git a/OpenAL32/Include/alFilter.h b/OpenAL32/Include/alFilter.h
index 83912cfa..11cb45cd 100644
--- a/OpenAL32/Include/alFilter.h
+++ b/OpenAL32/Include/alFilter.h
@@ -8,8 +8,8 @@ extern "C" {
#endif
typedef struct {
- float history[2]; /* history in filter */
- float coef[4 + 1]; /* coefficients of filter */
+ ALfloat history[4];
+ ALfloat coeff;
} FILTER;
#define AL_FILTER_TYPE 0x8001
@@ -53,8 +53,6 @@ ALvoid AL_APIENTRY alGetFilterfv(ALuint filter, ALenum param, ALfloat *pflValues
ALvoid ReleaseALFilters(ALvoid);
-int InitLowPassFilter(ALCcontext *Context, FILTER *iir);
-
#ifdef __cplusplus
}
#endif
diff --git a/OpenAL32/Include/alSource.h b/OpenAL32/Include/alSource.h
index 976921f9..753553b2 100644
--- a/OpenAL32/Include/alSource.h
+++ b/OpenAL32/Include/alSource.h
@@ -69,6 +69,7 @@ typedef struct ALsource
struct {
struct ALeffectslot *Slot;
ALfilter WetFilter;
+ FILTER iirFilter;
} Send[MAX_SENDS];
ALboolean DryGainHFAuto;
@@ -98,8 +99,6 @@ typedef struct ALsource
// Current gains, which are ramped while mixed
ALfloat DryGains[OUTPUTCHANNELS];
ALfloat WetGains[OUTPUTCHANNELS];
- ALfloat DryGainHF;
- ALfloat WetGainHF;
struct ALsource *next;
} ALsource;
diff --git a/OpenAL32/alAuxEffectSlot.c b/OpenAL32/alAuxEffectSlot.c
index 31218054..235d1b8d 100644
--- a/OpenAL32/alAuxEffectSlot.c
+++ b/OpenAL32/alAuxEffectSlot.c
@@ -71,8 +71,6 @@ ALvoid AL_APIENTRY alGenAuxiliaryEffectSlots(ALsizei n, ALuint *effectslots)
break;
}
- InitLowPassFilter(Context, &(*list)->iirFilter);
-
(*list)->Gain = 1.0;
(*list)->AuxSendAuto = AL_TRUE;
(*list)->refcount = 0;
diff --git a/OpenAL32/alSource.c b/OpenAL32/alSource.c
index fa07751f..fefbdf08 100644
--- a/OpenAL32/alSource.c
+++ b/OpenAL32/alSource.c
@@ -75,8 +75,6 @@ ALAPI ALvoid ALAPIENTRY alGenSources(ALsizei n,ALuint *sources)
break;
}
- InitLowPassFilter(Context, &(*list)->iirFilter);
-
sources[i] = (ALuint)ALTHUNK_ADDENTRY(*list);
(*list)->source = sources[i];
@@ -1406,8 +1404,6 @@ ALAPI ALvoid ALAPIENTRY alSourcePlayv(ALsizei n, const ALuint *pSourceList)
pSource->DryGains[j] = 0.0f;
pSource->WetGains[j] = 0.0f;
}
- pSource->DryGainHF = 0.0f;
- pSource->WetGainHF = 0.0f;
if (pSource->state != AL_PAUSED)
{