commit 030f749f5f6cb6570165039015d483c47454c18e
parent 21bb18780c6d149e53ca50ea21423e2349341571
Author: Friedolino <mkirchn@freenet.de>
Date: Sat, 14 Sep 2019 23:11:11 +0200
Optional LP filter for RND and SQR LFO (127=off)
Diffstat:
5 files changed, 73 insertions(+), 14 deletions(-)
diff --git a/src/Params/LFOParams.cpp b/src/Params/LFOParams.cpp
@@ -68,6 +68,8 @@ static const rtosc::Ports _ports = {
rParamZyn(Pstartphase, rShort("start"), rSpecial(random),
rDefaultDepends(loc), rDefault(64), rPreset(ad_voice_freq, 0),
"Starting Phase"),
+ rParamZyn(Pcutoff, rShort("lp"), rDefault(127),
+ "RND/SQR lp-filter freq"),
rOption(PLFOtype, rShort("type"), rOptions(sine, triangle, square, up, down,
exp1, exp2, random), rDefault(sine), "Shape of LFO"),
rParamZyn(Prandomness, rShort("a.r."), rSpecial(disable), rDefault(0),
@@ -143,13 +145,14 @@ void LFOParams::setup()
// TODO: reuse
LFOParams::LFOParams(const AbsTime *time_) :
- LFOParams(2.65, 0, 0, 0, 0, 0, 0, loc_unspecified, time_)
+ LFOParams(2.65, 0, 0, 127, 0, 0, 0, 0, loc_unspecified, time_)
{
}
LFOParams::LFOParams(float freq_,
char Pintensity_,
char Pstartphase_,
+ char Pcutoff_,
char PLFOtype_,
char Prandomness_,
float Pdelay_,
@@ -161,6 +164,7 @@ LFOParams::LFOParams(float freq_,
Dfreq = freq_;
Dintensity = Pintensity_;
Dstartphase = Pstartphase_;
+ Dcutoff = Pcutoff_;
DLFOtype = PLFOtype_;
Drandomness = Prandomness_;
Ddelay = Pdelay_;
@@ -175,12 +179,13 @@ LFOParams::LFOParams(consumer_location_t loc,
last_update_timestamp(0) {
auto init =
- [&](float freq_, char Pintensity_, char Pstartphase_, char PLFOtype_,
+ [&](float freq_, char Pintensity_, char Pstartphase_, char Pcutoff_, char PLFOtype_,
char Prandomness_, float delay_, char Pcontinous_)
{
Dfreq = freq_;
Dintensity = Pintensity_;
Dstartphase = Pstartphase_;
+ Dcutoff = Pcutoff_;
DLFOtype = PLFOtype_;
Drandomness = Prandomness_;
Ddelay = delay_;
@@ -189,12 +194,12 @@ LFOParams::LFOParams(consumer_location_t loc,
switch(loc)
{
- case ad_global_amp: init(6.49, 0, 64, 0, 0, 0, 0); break;
- case ad_global_freq: init(3.71, 0, 64, 0, 0, 0, 0); break;
- case ad_global_filter: init(6.49, 0, 64, 0, 0, 0, 0); break;
- case ad_voice_amp: init(11.25, 32, 64, 0, 0, 0.94, 0); break;
- case ad_voice_freq: init(1.19, 40, 0, 0, 0, 0, 0); break;
- case ad_voice_filter: init(1.19, 20, 64, 0, 0, 0, 0); break;
+ case ad_global_amp: init(6.49, 0, 64, 127, 0, 0, 0, 0); break;
+ case ad_global_freq: init(3.71, 0, 64, 127, 0, 0, 0, 0); break;
+ case ad_global_filter: init(6.49, 0, 64, 127, 0, 0, 0, 0); break;
+ case ad_voice_amp: init(11.25, 32, 64, 127, 0, 0, 0.94, 0); break;
+ case ad_voice_freq: init(1.19, 40, 0, 127, 0, 0, 0, 0); break;
+ case ad_voice_filter: init(1.19, 20, 64, 127, 0, 0, 0, 0); break;
default: throw std::logic_error("Invalid LFO consumer location");
}
@@ -209,6 +214,7 @@ void LFOParams::defaults()
freq = Dfreq;
Pintensity = Dintensity;
Pstartphase = Dstartphase;
+ Pcutoff = Dcutoff;
PLFOtype = DLFOtype;
Prandomness = Drandomness;
delay = Ddelay;
@@ -223,6 +229,7 @@ void LFOParams::add2XML(XMLwrapper& xml)
xml.addparreal("freq", freq);
xml.addpar("intensity", Pintensity);
xml.addpar("start_phase", Pstartphase);
+ xml.addpar("cutoff", Pcutoff);
xml.addpar("lfo_type", PLFOtype);
xml.addpar("randomness_amplitude", Prandomness);
xml.addpar("randomness_frequency", Pfreqrand);
@@ -240,6 +247,7 @@ void LFOParams::getfromXML(XMLwrapper& xml)
}
Pintensity = xml.getpar127("intensity", Pintensity);
Pstartphase = xml.getpar127("start_phase", Pstartphase);
+ Pcutoff = xml.getpar127("cutoff", Pcutoff);
PLFOtype = xml.getpar127("lfo_type", PLFOtype);
Prandomness = xml.getpar127("randomness_amplitude", Prandomness);
Pfreqrand = xml.getpar127("randomness_frequency", Pfreqrand);
@@ -259,6 +267,7 @@ void LFOParams::paste(LFOParams &x)
COPY(freq);
COPY(Pintensity);
COPY(Pstartphase);
+ COPY(Pcutoff);
COPY(PLFOtype);
COPY(Prandomness);
COPY(Pfreqrand);
diff --git a/src/Params/LFOParams.h b/src/Params/LFOParams.h
@@ -40,6 +40,7 @@ class LFOParams:public Presets
LFOParams(float freq_,
char Pintensity_,
char Pstartphase_,
+ char Pcutoff_,
char PLFOtype_,
char Prandomness_,
float delay_,
@@ -58,6 +59,7 @@ class LFOParams:public Presets
float freq; /**<frequency*/
unsigned char Pintensity; /**<intensity*/
unsigned char Pstartphase; /**<start phase (0=random)*/
+ unsigned char Pcutoff; /**<cutoff */
unsigned char PLFOtype; /**<LFO type (sin,triangle,square,ramp,...)*/
unsigned char Prandomness; /**<randomness (0=off)*/
unsigned char Pfreqrand; /**<frequency randomness (0=off)*/
@@ -81,6 +83,7 @@ class LFOParams:public Presets
float Dfreq;
unsigned char Dintensity;
unsigned char Dstartphase;
+ unsigned char Dcutoff;
unsigned char DLFOtype;
unsigned char Drandomness;
float Ddelay;
diff --git a/src/Synth/LFO.cpp b/src/Synth/LFO.cpp
@@ -79,6 +79,8 @@ LFO::LFO(const LFOParams &lfopars, float basefreq, const AbsTime &t, WatchManage
incrnd = nextincrnd = 1.0f;
computeNextFreqRnd();
computeNextFreqRnd(); //twice because I want incrnd & nextincrnd to be random
+ z1 = 0.0;
+ z2 = 0.0;
}
LFO::~LFO()
@@ -86,6 +88,7 @@ LFO::~LFO()
float LFO::baseOut(const char waveShape, const float phase)
{
+ float lfo_out;
switch(waveShape) {
case LFO_TRIANGLE:
if(phase >= 0.0f && phase < 0.25f)
@@ -97,9 +100,11 @@ float LFO::baseOut(const char waveShape, const float phase)
break;
case LFO_SQUARE:
if(phase < 0.5f)
- return -1;
+ lfo_out = -1;
else
- return 1;
+ lfo_out = 1;
+
+ return biquad(lfo_out);
break;
case LFO_RAMPUP: return (phase - 0.5f) * 2.0f;
case LFO_RAMPDOWN: return (0.5f - phase) * 2.0f;
@@ -110,12 +115,36 @@ float LFO::baseOut(const char waveShape, const float phase)
first_half = phase < 0.5;
last_random = 2*RND-1;
}
- return last_random;
- default: return cosf(phase * 2.0f * PI); //LFO_SINE
+
+
+ return biquad(last_random);
+ break;
+ default:
+ return cosf(phase * 2.0f * PI); //LFO_SINE
}
}
+float LFO::biquad(float input)
+{
+ float output;
+ // calculate biquad coefficients
+ Fc = powf(lfopars_.Pcutoff + 7.0f, 2.0f)/127.0f;
+ K = tan(PI * Fc * dt_);
+ norm = 1 / (1 + K / 0.7071f + K * K);
+ a0 = K * K * norm;
+ a1 = 2 * a0;
+ a2 = a0;
+ b1 = 2 * (K * K - 1) * norm;
+ b2 = (1 - K / 0.7071f + K * K) * norm;
+ // lp filter the (s&h) random LFO
+ output = input * a0 + z1;
+ z1 = input * a1 + z2 - b1 * output;
+ z2 = input * a2 - b2 * output;
+ return (lfopars_.Pcutoff==127) ? input : output;
+}
+
+
float LFO::lfoout()
{
//update internals XXX TODO cleanup
diff --git a/src/Synth/LFO.h b/src/Synth/LFO.h
@@ -37,6 +37,7 @@ class LFO
float amplfoout();
private:
float baseOut(const char waveShape, const float phase);
+ float biquad(float input);
//Phase of Oscillator
float phase;
//Phase Increment Per Frame
@@ -49,6 +50,7 @@ class LFO
// RND mode
int first_half;
float last_random;
+ float z1, z2, noisy_out;
//Intensity of the wave
float lfointensity;
@@ -66,6 +68,15 @@ class LFO
const float dt_;
const LFOParams &lfopars_;
const float basefreq_;
+
+ float Fc, K, norm;
+
+ //biquad coefficients for lp filtering in noise-LFO
+ float a0 = 0.0007508914611009499;
+ float a1 = 0.0015017829222018998;
+ float a2 = 0.0007508914611009499;
+ float b1 = -1.519121359805288;
+ float b2 = 0.5221249256496917;
VecWatchPoint watchOut;
diff --git a/src/UI/LFOUI.fl b/src/UI/LFOUI.fl
@@ -79,15 +79,21 @@ hide();} {}
code0 {o->init("Pintensity");}
class Fl_Osc_Dial
}
+ Fl_Dial cutoff {
+ label LP
+ tooltip {LP cutoff} xywh {70 30 20 20} box ROUND_UP_BOX labelsize 10 maximum 127 step 1
+ code0 {o->init("Pcutoff");}
+ class Fl_Osc_Dial
+ }
Fl_Dial delay {
label Delay
- tooltip {LFO delay} xywh {110 20 30 30} box ROUND_UP_BOX labelsize 10 maximum 127 step 1
+ tooltip {LFO delay} xywh {120 30 20 20} box ROUND_UP_BOX labelsize 10 maximum 127 step 1
code0 {o->init("Pdelay");}
class Fl_Osc_Dial
}
Fl_Dial startphase {
label Start
- tooltip {LFO Startphase (leftmost is Random)} xywh {75 20 30 30} box ROUND_UP_BOX labelsize 10 maximum 127 step 1
+ tooltip {LFO Startphase (leftmost is Random)} xywh {95 20 20 20} box ROUND_UP_BOX labelsize 10 maximum 127 step 1
code0 {o->init("Pstartphase");}
class Fl_Osc_Dial
}
@@ -172,6 +178,7 @@ hide();} {}
code {freq->update();
intensity->update();
startphase->update();
+cutoff->update();
delay->update();
continous->update();
stretch->update();
