formatting cleanup

This commit is contained in:
Gordon JC Pearce 2025-12-28 12:08:42 +00:00
parent 36c27f14d8
commit ad7b7f4405
2 changed files with 120 additions and 108 deletions

View File

@ -48,6 +48,7 @@ class Module {
float saw = 0, square = 0, sub = 0, noise = 0; float saw = 0, square = 0, sub = 0, noise = 0;
/*
#if 0 #if 0
struct { struct {
uint8_t lfoRate = 0x58; uint8_t lfoRate = 0x58;
@ -92,6 +93,29 @@ class Module {
uint8_t switch2 = 0x1d; uint8_t switch2 = 0x1d;
} patchRam; } patchRam;
#endif #endif
*/
struct {
uint8_t lfoRate = 0x58;
uint8_t lfoDelay = 0x00;
uint8_t vcoLfo = 0x00;
uint8_t pwmLfo = 0x00;
uint8_t noise = 0x00;
uint8_t vcfFreq = 0x00; // 1c; // 0x3f80
uint8_t vcfReso = 0x7f;
uint8_t vcfEnv = 0x7f; // 4e;
uint8_t vcfLfo = 0x00;
uint8_t vcfKey = 0x00; // 47;
uint8_t vca = 0x20;
uint8_t env_a = 0x00;
uint8_t env_d = 0x5c;
uint8_t env_s = 0x00; // 0x3f80
uint8_t env_r = 0x3c;
uint8_t sub = 0x7f;
uint8_t switch1 = 0x3a;
uint8_t switch2 = 0x19;
} patchRam;
Chorus* chorus; Chorus* chorus;
float vcaTC; float vcaTC;
@ -128,7 +152,7 @@ class Voice {
uint8_t envPhase = 0; uint8_t envPhase = 0;
int16_t env = 0; // output amplitude int16_t env = 0; // output amplitude
int16_t vcfCut; uint16_t vcfCut;
int16_t vcaEnv; int16_t vcaEnv;
float vcaRC = 0, vcfRC = 0; float vcaRC = 0, vcfRC = 0;
@ -137,6 +161,7 @@ class Voice {
// filter // filter
float y0 = 0, y1 = 0, y2 = 0, y3 = 0; float y0 = 0, y1 = 0, y2 = 0, y3 = 0;
double s[4] = {0, 0, 0, 0}; double s[4] = {0, 0, 0, 0};
float zi = 0;
}; };
#endif #endif

View File

@ -50,45 +50,26 @@ void Voice::off() {
envPhase = 0; envPhase = 0;
} }
// tanh(x)/x approximation, flatline at very high inputs // tanh(x)/x approximation, flatline at very high inputs
// so might not be safe for very large feedback gains // so might not be safe for very large feedback gains
// [limit is 1/15 so very large means ~15 or +23dB] // [limit is 1/15 so very large means ~15 or +23dB]
double tanhXdX(double x) { double tanhXdX(double x) {
float s = 0.0333, d = 30.0;
return 1.0f - s * (d + 1.0f) * x * x / (d + x * x);
return 1-0.1*abs(x);
double a = x*x;
// IIRC I got this as Pade-approx for tanh(sqrt(x))/sqrt(x)
return ((a + 105)*a + 945) / ((15*a + 420)*a + 945);
} }
void Voice::run(Module* m, float* buffer, uint32_t samples) { void Voice::run(Module* m, float* buffer, uint32_t samples) {
// carry out per-voice calculations for each block of samples // carry out per-voice calculations for each block of samples
float out, t, fb; float out, t, fb;
double zi;
// calculate cutoff frequency // calculate cutoff frequency
float cut = 248.0f * (powf(2, (vcfCut - 0x1880) / 1143.0f)); float cut = 261.0f * (powf(2, (vcfCut - 0x1880) / 1143.0f));
cut = M_PI * cut / sampleRate; cut = M_PI * cut / sampleRate;
cut = cut / (1 + cut); // correct tuning warp cut = cut / (1 + cut); // correct tuning warp
// if (cut > 0.7) cut = 0.7;
double r = 5 * m->res;
// printf("%f\n", cut);
//if (cut > 0.5) cut = 0.5;
// double f = tan(cut);
//printf("cut = %4f f = %4f\n", cut, f);
double r = (40.0/9.0) * m->res;
float amp = vcaEnv / 4096.0f; float amp = vcaEnv / 4096.0f;
@ -128,7 +109,7 @@ double zi;
delay += m->subBuf[i] * subosc; delay += m->subBuf[i] * subosc;
out += m->noise * (0.8 - 1.6 * (rand() & 0xffff) / 65536.0); out += m->noise * (0.8 - 1.6 * (rand() & 0xffff) / 65536.0);
out *= 0.01; // out *= 0.1;
// same time constant for both VCF and VCF RC circuits // same time constant for both VCF and VCF RC circuits
vcfRC = (cut - vcfRC) * m->vcaTC + vcfRC; vcfRC = (cut - vcfRC) * m->vcaTC + vcfRC;
@ -157,8 +138,11 @@ double zi;
//------------------------------------------------------------------------------ sample loop //------------------------------------------------------------------------------ sample loop
// for(unsigned n = 0; n < nsamples; ++n) // for(unsigned n = 0; n < nsamples; ++n)
//{ //{
out *= 0.025;
// input with half delay, for non-linearities // input with half delay, for non-linearities
double ih = 0.5 * (out + zi); zi = out; double ih = 0.5 * (out + zi);
zi = out;
// double ih = out; // double ih = out;
@ -196,14 +180,17 @@ double zi;
// out[n] = y3; // out[n] = y3;
// } // }
// out *= 0.1;
out = y3;
#else #else
for (uint8_t ovs = 0; ovs < 4; ovs++) { out *= 0.5;
for (uint8_t ovs = 0; ovs < 2; ovs++) {
fb = y3; fb = y3;
// hard clip // hard clip
fb = ((out * 0.5) - fb) * m->res; fb = ((out * 0.5) - fb) * r;
if (fb > 4) fb = 4; if (fb > 4) fb = 4;
if (fb < -4) fb = -4; if (fb < -4) fb = -4;
// fb = 1.5 * fb - 0.5 * fb * fb * fb; // fb = 1.5 * fb - 0.5 * fb * fb * fb;
@ -216,7 +203,7 @@ double zi;
} }
#endif #endif
vcaRC = (amp - vcaRC) * m->vcaTC + vcaRC; vcaRC = (amp - vcaRC) * m->vcaTC + vcaRC;
buffer[i] += 1 * m->vcaBuf[i] * vcaRC * y3; buffer[i] += m->vcaBuf[i] * vcaRC * out;
lastpw = m->pwmBuf[i]; lastpw = m->pwmBuf[i];
} }