void fft_compute_split_twiddle(MYFLT **twiddle, int size) {
/* pre-compute split-radix twiddle factors in 2d array of length [4][size>>3] */
int j;
int n8 = size >> 3;
MYFLT e = 2.0 * PI / size;
MYFLT a = e;
MYFLT a3;
for(j=2; j<=n8; j++) {
a3 = 3 * a;
twiddle[0][j-1] = MYCOS(a);
twiddle[1][j-1] = MYSIN(a);
twiddle[2][j-1] = MYCOS(a3);
twiddle[3][j-1] = MYSIN(a3);
a = j * e;
}
return;
}
void fft_compute_radix2_twiddle(MYFLT *twiddle, int size) {
/* pre-compute radix-2 twiddle factors in one array of length n */
/* re[0], re[1], ..., re[n/2-1], im[0], im[1], ..., im[n/2-1] */
int i;
int hsize = size / 2;
for (i=0; i<hsize; i++) {
twiddle[i] = MYCOS(TWOPI/hsize*i);
twiddle[hsize+i] = MYSIN(TWOPI/hsize*i);
}
}
static void
BandSplitter_compute_variables(BandSplitter *self, MYFLT q)
{
int i;
MYFLT freq;
for (i=0; i<self->bands; i++) {
freq = self->band_freqs[i];
if (freq <= 1)
freq = 1;
else if (freq >= self->halfSr)
freq = self->halfSr;
MYFLT w0 = self->TwoPiOnSr * freq;
MYFLT c = MYCOS(w0);
MYFLT alpha = MYSIN(w0) / (2 * q);
self->b0[i] = alpha;
self->b2[i] = -alpha;
self->a0[i] = 1 + alpha;
self->a1[i] = -2 * c;
self->a2[i] = 1 - alpha;
}
}
static void
LFO_generates_aa(LFO *self) {
MYFLT val, inc, freq, sharp, pointer, numh;
MYFLT v1, v2, inc2, fade;
MYFLT sharp2 = 0.0;
int i, maxHarms;
MYFLT *fr = Stream_getData((Stream *)self->freq_stream);
MYFLT *sh = Stream_getData((Stream *)self->sharp_stream);
switch (self->wavetype) {
case 0: /* Saw up */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverFour/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
pointer = self->pointerPos * 2.0 - 1.0;
val = pointer - MYTANH(numh * pointer) / MYTANH(numh);
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 1: /* Saw down */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverFour/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
pointer = self->pointerPos * 2.0 - 1.0;
val = -(pointer - MYTANH(numh * pointer) / MYTANH(numh));
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 2: /* Square */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverEight/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
val = MYATAN(numh * MYSIN(TWOPI*self->pointerPos));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 3: /* Triangle */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverFour/freq);
if ((sharp * 36.0) > maxHarms)
numh = (MYFLT)(maxHarms / 36.0);
else
numh = sharp;
v1 = MYTAN(MYSIN(TWOPI*self->pointerPos)) * self->oneOverPiOverTwo;
pointer = self->pointerPos + 0.25;
if (pointer > 1.0)
pointer -= 1.0;
v2 = 4.0 * (0.5 - MYFABS(pointer - 0.5)) - 1.0;
val = v1 * (1 - numh) + v2 * numh;
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 4: /* Pulse */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverEight/freq);
numh = MYFLOOR(sharp * 46.0 + 4.0);
if (numh > maxHarms)
numh = maxHarms;
if (MYFMOD(numh, 2.0) == 0.0)
numh += 1.0;
val = MYTAN(MYPOW(MYFABS(MYSIN(TWOPI*self->pointerPos)), numh));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 5: /* Bi-Pulse */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
maxHarms = (int)(self->srOverEight/freq);
numh = MYFLOOR(sharp * 46.0 + 4.0);
if (numh > maxHarms)
numh = maxHarms;
if (MYFMOD(numh, 2.0) == 0.0)
numh += 1.0;
val = MYTAN(MYPOW(MYSIN(TWOPI*self->pointerPos), numh));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 6: /* SAH */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
numh = 1.0 - sharp;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
inc2 = 1.0 / (int)(1.0 / inc * numh);
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1) {
self->pointerPos -= 1.0;
self->sahPointerPos = 0.0;
self->sahLastValue = self->sahCurrentValue;
self->sahCurrentValue = RANDOM_UNIFORM * 2.0 - 1.0;
}
if (self->sahPointerPos < 1.0) {
fade = 0.5 * MYSIN(PI * (self->sahPointerPos+0.5)) + 0.5;
val = self->sahCurrentValue * (1.0 - fade) + self->sahLastValue * fade;
self->sahPointerPos += inc2;
}
else {
val = self->sahCurrentValue;
}
self->data[i] = val;
}
break;
case 7: /* Sine-mod */
for (i=0; i<self->bufsize; i++) {
sharp = sh[i];
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
freq = fr[i];
if (freq < 0.00001)
freq = 0.00001;
else if (freq > self->srOverFour)
freq = self->srOverFour;
inc = freq * self->oneOverSr;
inc2 = inc * sharp * 0.99;
sharp2 = sharp * 0.5;
self->modPointerPos += inc2;
if (self->modPointerPos < 0)
self->modPointerPos += 1.0;
else if (self->modPointerPos >= 1)
self->modPointerPos -= 1.0;
val = ((sharp2 * MYCOS(TWOPI*self->modPointerPos) + sharp2) + (1.0 - sharp)) * MYSIN(TWOPI*self->pointerPos);
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
default:
break;
}
}
static void
LFO_generates_ii(LFO *self) {
MYFLT val, inc, freq, sharp, pointer, numh;
MYFLT v1, v2, inc2, fade;
int i, maxHarms;
freq = PyFloat_AS_DOUBLE(self->freq);
if (freq <= 0) {
return;
}
sharp = PyFloat_AS_DOUBLE(self->sharp);
if (sharp < 0.0)
sharp = 0.0;
else if (sharp > 1.0)
sharp = 1.0;
inc = freq / self->sr;
switch (self->wavetype) {
case 0: /* Saw up */
maxHarms = (int)(self->srOverFour/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
for (i=0; i<self->bufsize; i++) {
pointer = self->pointerPos * 2.0 - 1.0;
val = pointer - MYTANH(numh * pointer) / MYTANH(numh);
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 1: /* Saw down */
maxHarms = (int)(self->srOverFour/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
for (i=0; i<self->bufsize; i++) {
pointer = self->pointerPos * 2.0 - 1.0;
val = -(pointer - MYTANH(numh * pointer) / MYTANH(numh));
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 2: /* Square */
maxHarms = (int)(self->srOverEight/freq);
numh = sharp * 46.0 + 4.0;
if (numh > maxHarms)
numh = maxHarms;
for (i=0; i<self->bufsize; i++) {
val = MYATAN(numh * MYSIN(TWOPI*self->pointerPos));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 3: /* Triangle */
maxHarms = (int)(self->srOverFour/freq);
if ((sharp * 36.0) > maxHarms)
numh = (MYFLT)(maxHarms / 36.0);
else
numh = sharp;
for (i=0; i<self->bufsize; i++) {
v1 = MYTAN(MYSIN(TWOPI*self->pointerPos)) * self->oneOverPiOverTwo;
pointer = self->pointerPos + 0.25;
if (pointer > 1.0)
pointer -= 1.0;
v2 = 4.0 * (0.5 - MYFABS(pointer - 0.5)) - 1.0;
val = v1 * (1 - numh) + v2 * numh;
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 4: /* Pulse */
maxHarms = (int)(self->srOverEight/freq);
numh = MYFLOOR(sharp * 46.0 + 4.0);
if (numh > maxHarms)
numh = maxHarms;
if (MYFMOD(numh, 2.0) == 0.0)
numh += 1.0;
for (i=0; i<self->bufsize; i++) {
val = MYTAN(MYPOW(MYFABS(MYSIN(TWOPI*self->pointerPos)), numh));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 5: /* Bi-Pulse */
maxHarms = (int)(self->srOverEight/freq);
numh = MYFLOOR(sharp * 46.0 + 4.0);
if (numh > maxHarms)
numh = maxHarms;
if (MYFMOD(numh, 2.0) == 0.0)
numh += 1.0;
for (i=0; i<self->bufsize; i++) {
val = MYTAN(MYPOW(MYSIN(TWOPI*self->pointerPos), numh));
self->data[i] = val * self->oneOverPiOverTwo;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
case 6: /* SAH */
numh = 1.0 - sharp;
inc2 = 1.0 / (int)(1.0 / inc * numh);
for (i=0; i<self->bufsize; i++) {
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1) {
self->pointerPos -= 1.0;
self->sahPointerPos = 0.0;
self->sahLastValue = self->sahCurrentValue;
self->sahCurrentValue = rand()/((MYFLT)(RAND_MAX)*0.5) - 1.0;
}
if (self->sahPointerPos < 1.0) {
fade = 0.5 * MYSIN(PI * (self->sahPointerPos+0.5)) + 0.5;
val = self->sahCurrentValue * (1.0 - fade) + self->sahLastValue * fade;
self->sahPointerPos += inc2;
}
else {
val = self->sahCurrentValue;
}
self->data[i] = val;
}
break;
case 7: /* Sine-mod */
inc2 = inc * sharp;
for (i=0; i<self->bufsize; i++) {
self->modPointerPos += inc2;
if (self->modPointerPos < 0)
self->modPointerPos += 1.0;
else if (self->modPointerPos >= 1)
self->modPointerPos -= 1.0;
val = (0.5 * MYCOS(TWOPI*self->modPointerPos) + 0.5) * MYSIN(TWOPI*self->pointerPos);
self->data[i] = val;
self->pointerPos += inc;
if (self->pointerPos < 0)
self->pointerPos += 1.0;
else if (self->pointerPos >= 1)
self->pointerPos -= 1.0;
}
break;
default:
break;
}
}
