Added new version of Synth_Dexed.

dev
Holger Wirtz 3 years ago
parent 6b6de64b20
commit 0aca775809
  1. 237
      third-party/Synth_Dexed/src/PluginFx.cpp
  2. 73
      third-party/Synth_Dexed/src/PluginFx.h
  3. 34
      third-party/Synth_Dexed/src/aligned_buf.h
  4. 154
      third-party/Synth_Dexed/src/controllers.h
  5. 1502
      third-party/Synth_Dexed/src/dexed.cpp
  6. 327
      third-party/Synth_Dexed/src/dexed.h
  7. 388
      third-party/Synth_Dexed/src/dx7note.cpp
  8. 82
      third-party/Synth_Dexed/src/dx7note.h
  9. 190
      third-party/Synth_Dexed/src/env.cpp
  10. 81
      third-party/Synth_Dexed/src/env.h
  11. 70
      third-party/Synth_Dexed/src/exp2.cpp
  12. 80
      third-party/Synth_Dexed/src/exp2.h
  13. 50
      third-party/Synth_Dexed/src/fast_log.h
  14. 144
      third-party/Synth_Dexed/src/fm_core.cpp
  15. 58
      third-party/Synth_Dexed/src/fm_core.h
  16. 280
      third-party/Synth_Dexed/src/fm_op_kernel.cpp
  17. 47
      third-party/Synth_Dexed/src/fm_op_kernel.h
  18. 56
      third-party/Synth_Dexed/src/freqlut.cpp
  19. 23
      third-party/Synth_Dexed/src/freqlut.h
  20. 97
      third-party/Synth_Dexed/src/lfo.cpp
  21. 43
      third-party/Synth_Dexed/src/lfo.h
  22. 93
      third-party/Synth_Dexed/src/pitchenv.cpp
  23. 52
      third-party/Synth_Dexed/src/pitchenv.h
  24. 35
      third-party/Synth_Dexed/src/porta.cpp
  25. 28
      third-party/Synth_Dexed/src/porta.h
  26. 144
      third-party/Synth_Dexed/src/sin.cpp
  27. 62
      third-party/Synth_Dexed/src/sin.h
  28. 81
      third-party/Synth_Dexed/src/synth.h
  29. 3322
      third-party/Synth_Dexed/src/synth_dexed.cpp
  30. 1249
      third-party/Synth_Dexed/src/synth_dexed.h
  31. 50
      third-party/Synth_Dexed/src/teensy_board_detection.h

@ -0,0 +1,237 @@
/**
Copyright (c) 2013-2014 Pascal Gauthier.
Copyright (c) 2013-2014 Filatov Vadim.
Filter taken from the Obxd project :
https://github.com/2DaT/Obxd
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#define _USE_MATH_DEFINES
#include <math.h>
#include "PluginFx.h"
#include "synth.h"
const float dc = 1e-18;
inline static float tptpc(float& state, float inp, float cutoff) {
float v = (inp - state) * cutoff / (1 + cutoff);
float res = v + state;
state = res + v;
return res;
}
inline static float tptlpupw(float & state , float inp , float cutoff , float srInv) {
cutoff = (cutoff * srInv) * M_PI;
float v = (inp - state) * cutoff / (1 + cutoff);
float res = v + state;
state = res + v;
return res;
}
//static float linsc(float param,const float min,const float max) {
// return (param) * (max - min) + min;
//}
/*
static float logsc(float param, const float min, const float max, const float rolloff = 19.0f) {
return ((EXP_FUNC(param * LOG_FUNC(rolloff + 1)) - 1.0f) / (rolloff)) * (max - min) + min;
}
*/
PluginFx::PluginFx() {
Cutoff = 1.0;
Reso = 0.0;
Gain = 1.0;
}
void PluginFx::init(int sr) {
mm = 0;
s1 = s2 = s3 = s4 = c = d = 0;
R24 = 0;
mmch = (int)(mm * 3);
mmt = mm * 3 - mmch;
sampleRate = sr;
sampleRateInv = 1 / sampleRate;
#if defined(ARM_SQRT_FUNC)
float rcrate; ARM_SQRT_FUNC(44000 / sampleRate, &rcrate);
#else
float rcrate = SQRT_FUNC((44000 / sampleRate));
#endif
rcor24 = (970.0 / 44000) * rcrate;
rcor24Inv = 1 / rcor24;
bright = tanf((sampleRate * 0.5f - 10) * M_PI * sampleRateInv);
R = 1;
rcor = (480.0 / 44000) * rcrate;
rcorInv = 1 / rcor;
bandPassSw = false;
pCutoff = -1;
pReso = -1;
dc_r = 1.0 - (126.0 / sr);
dc_id = 0;
dc_od = 0;
}
inline float PluginFx::NR24(float sample, float g, float lpc) {
float ml = 1 / (1 + g);
float S = (lpc * (lpc * (lpc * s1 + s2) + s3) + s4) * ml;
float G = lpc * lpc * lpc * lpc;
float y = (sample - R24 * S) / (1 + R24 * G);
return y + 1e-8;
};
inline float PluginFx::NR(float sample, float g) {
float y = ((sample - R * s1 * 2 - g * s1 - s2) / (1 + g * (2 * R + g))) + dc;
return y;
}
void PluginFx::process(float *work, int sampleSize) {
// very basic DC filter
float t_fd = work[0];
work[0] = work[0] - dc_id + dc_r * dc_od;
dc_id = t_fd;
for (int i = 1; i < sampleSize; i++) {
t_fd = work[i];
work[i] = work[i] - dc_id + dc_r * work[i - 1];
dc_id = t_fd;
}
dc_od = work[sampleSize - 1];
// Gain
if (Gain == 0.0)
{
for (int i = 0; i < sampleSize; i++ )
work[i] = 0.0;
}
else if ( Gain != 1.0)
{
for (int i = 0; i < sampleSize; i++ )
work[i] *= Gain;
}
#ifdef USE_FX
// don't apply the LPF if the cutoff is to maximum
if ( Cutoff == 1.0 )
return;
if ( Cutoff != pCutoff || Reso != pReso ) {
rReso = (0.991 - logsc(1 - Reso, 0, 0.991));
R24 = 3.5 * rReso;
float cutoffNorm = logsc(Cutoff, 60, 19000);
rCutoff = (float)tanf(cutoffNorm * sampleRateInv * M_PI);
pCutoff = Cutoff;
pReso = Reso;
R = 1 - rReso;
}
// THIS IS MY FAVORITE 4POLE OBXd filter
// maybe smooth this value
float g = rCutoff;
float lpc = g / (1 + g);
for (int i = 0; i < sampleSize; i++ ) {
float s = work[i];
s = s - 0.45 * tptlpupw(c, s, 15, sampleRateInv);
s = tptpc(d, s, bright);
float y0 = NR24(s, g, lpc);
//first low pass in cascade
float v = (y0 - s1) * lpc;
float res = v + s1;
s1 = res + v;
//damping
s1 = atanf(s1 * rcor24) * rcor24Inv;
float y1 = res;
float y2 = tptpc(s2, y1, g);
float y3 = tptpc(s3, y2, g);
float y4 = tptpc(s4, y3, g);
float mc = 0.0;
switch (mmch) {
case 0:
mc = ((1 - mmt) * y4 + (mmt) * y3);
break;
case 1:
mc = ((1 - mmt) * y3 + (mmt) * y2);
break;
case 2:
mc = ((1 - mmt) * y2 + (mmt) * y1);
break;
case 3:
mc = y1;
break;
}
//half volume comp
work[i] = mc * (1 + R24 * 0.45);
}
#endif
}
/*
// THIS IS THE 2POLE FILTER
for(int i=0; i < sampleSize; i++ ) {
float s = work[i];
s = s - 0.45*tptlpupw(c,s,15,sampleRateInv);
s = tptpc(d,s,bright);
//float v = ((sample- R * s1*2 - g2*s1 - s2)/(1+ R*g1*2 + g1*g2));
float v = NR(s,g);
float y1 = v*g + s1;
//damping
s1 = atanf(s1 * rcor) * rcorInv;
float y2 = y1*g + s2;
s2 = y2 + y1*g;
float mc;
if(!bandPassSw)
mc = (1-mm)*y2 + (mm)*v;
else
{
mc =2 * ( mm < 0.5 ?
((0.5 - mm) * y2 + (mm) * y1):
((1-mm) * y1 + (mm-0.5) * v)
);
}
work[i] = mc;
}
*/
float PluginFx::getGain(void)
{
return (Gain);
}

@ -0,0 +1,73 @@
/**
Copyright (c) 2013 Pascal Gauthier.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef PLUGINFX_H_INCLUDED
#define PLUGINFX_H_INCLUDED
class PluginFx {
float s1, s2, s3, s4;
float sampleRate;
float sampleRateInv;
float d, c;
float R24;
float rcor24, rcor24Inv;
float bright;
// 24 db multimode
float mm;
float mmt;
int mmch;
inline float NR24(float sample, float g, float lpc);
// preprocess values taken the UI
float rCutoff;
float rReso;
float rGain;
// thread values; if these are different from the UI,
// it needs to be recalculated.
float pReso;
float pCutoff;
float pGain;
// I am still keeping the 2pole w/multimode filter
inline float NR(float sample, float g);
bool bandPassSw;
float rcor, rcorInv;
int R;
float dc_id;
float dc_od;
float dc_r;
public:
PluginFx();
// this is set directly by the ui / parameter
float Cutoff;
float Reso;
float Gain;
void init(int sampleRate);
void process(float *work, int sampleSize);
float getGain(void);
};
#endif

@ -0,0 +1,34 @@
/*
Copyright 2013 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// A convenient wrapper for buffers with alignment constraints
// Note that if we were on C++11, we'd use aligned_storage or somesuch.
#ifndef __ALIGNED_BUF_H
#define __ALIGNED_BUF_H
template<typename T, size_t size, size_t alignment = 16>
class AlignedBuf {
public:
T *get() {
return (T *)((((intptr_t)storage_) + alignment - 1) & -alignment);
}
private:
unsigned char storage_[size * sizeof(T) + alignment];
};
#endif

@ -0,0 +1,154 @@
/*
Copyright 2013 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef __CONTROLLERS_H
#define __CONTROLLERS_H
#include <Arduino.h>
#include "synth.h"
#include <stdio.h>
#include <string.h>
#include <math.h>
// State of MIDI controllers
const int kControllerPitch = 0;
const int kControllerPitchRange = 1;
const int kControllerPitchStep = 2;
const int kControllerPortamentoGlissando = 3;
class FmCore;
class FmMod {
public:
uint8_t range;
bool pitch;
bool amp;
bool eg;
uint8_t ctrl_mode;
uint8_t _dummy_;
FmMod()
{
range = 0;
ctrl_mode = 0;
pitch = false;
amp = false;
eg = false;
}
void setRange(uint8_t r)
{
range = r < 0 || r > 99 ? 0 : r;
}
uint8_t getRange(void)
{
return (range);
}
void setTarget(uint8_t assign)
{
assign = assign < 0 && assign > 7 ? 0 : assign;
pitch = assign & 1; // PITCH
amp = assign & 2; // AMP
eg = assign & 4; // EG
}
uint8_t getTarget(void)
{
return (pitch & amp & eg);
}
void setMode(uint8_t m)
{
ctrl_mode = m > MIDI_CONTROLLER_MODE_MAX ? 0 : m;
}
};
class Controllers {
void applyMod(int cc, FmMod &mod)
{
uint8_t total = 0;
float range = mod.range / 100.0;
switch (mod.ctrl_mode)
{
case 0:
total = uint8_t(float(cc) * range); // LINEAR mode
break;
case 1:
total = uint8_t(127.0 * range - (float(cc) * range)); // REVERSE mode
break;
case 2:
total = uint8_t(range * float(cc) + (1.0 - range) * 127.0); // DIRECT BC mode by Thierry (opus.quatre)
break;
}
if (mod.amp)
amp_mod = max(amp_mod, total);
if (mod.pitch)
pitch_mod = max(pitch_mod, total);
if (mod.eg)
eg_mod = max(eg_mod, total);
}
public:
int32_t values_[4];
uint8_t amp_mod;
uint8_t pitch_mod;
uint8_t eg_mod;
uint8_t aftertouch_cc;
uint8_t breath_cc;
uint8_t foot_cc;
uint8_t modwheel_cc;
bool portamento_enable_cc;
int portamento_cc;
bool portamento_gliss_cc;
int masterTune;
uint8_t opSwitch;
FmMod wheel;
FmMod foot;
FmMod breath;
FmMod at;
Controllers() {
amp_mod = 0;
pitch_mod = 0;
eg_mod = 0;
}
void refresh() {
amp_mod = pitch_mod = eg_mod = 0;
applyMod(modwheel_cc, wheel);
applyMod(breath_cc, breath);
applyMod(foot_cc, foot);
applyMod(aftertouch_cc, at);
if ( ! ((wheel.eg || foot.eg) || (breath.eg || at.eg)) )
eg_mod = 127;
}
FmCore *core;
};
#endif

File diff suppressed because it is too large Load Diff

@ -0,0 +1,327 @@
/*
MicroDexed
MicroDexed is a port of the Dexed sound engine
(https://github.com/asb2m10/dexed) for the Teensy-3.5/3.6/4.x with audio shield.
Dexed ist heavily based on https://github.com/google/music-synthesizer-for-android
(c)2018-2021 H. Wirtz <wirtz@parasitstudio.de>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef DEXED_H_INCLUDED
#define DEXED_H_INCLUDED
#include <Arduino.h>
#include <Audio.h>
#include "fm_op_kernel.h"
#include "synth.h"
#include "env.h"
#include "aligned_buf.h"
#include "pitchenv.h"
#include "controllers.h"
#include "dx7note.h"
#include "lfo.h"
#include "PluginFx.h"
#define NUM_VOICE_PARAMETERS 156
struct ProcessorVoice {
int16_t midi_note;
uint8_t velocity;
int16_t porta;
bool keydown;
bool sustained;
bool live;
uint32_t key_pressed_timer;
Dx7Note *dx7_note;
};
enum DexedVoiceOPParameters {
DEXED_OP_EG_R1, // 0
DEXED_OP_EG_R2, // 1
DEXED_OP_EG_R3, // 2
DEXED_OP_EG_R4, // 3
DEXED_OP_EG_L1, // 4
DEXED_OP_EG_L2, // 5
DEXED_OP_EG_L3, // 6
DEXED_OP_EG_L4, // 7
DEXED_OP_LEV_SCL_BRK_PT, // 8
DEXED_OP_SCL_LEFT_DEPTH, // 9
DEXED_OP_SCL_RGHT_DEPTH, // 10
DEXED_OP_SCL_LEFT_CURVE, // 11
DEXED_OP_SCL_RGHT_CURVE, // 12
DEXED_OP_OSC_RATE_SCALE, // 13
DEXED_OP_AMP_MOD_SENS, // 14
DEXED_OP_KEY_VEL_SENS, // 15
DEXED_OP_OUTPUT_LEV, // 16
DEXED_OP_OSC_MODE, // 17
DEXED_OP_FREQ_COARSE, // 18
DEXED_OP_FREQ_FINE, // 19
DEXED_OP_OSC_DETUNE // 20
};
#define DEXED_VOICE_OFFSET 126
enum DexedVoiceParameters {
DEXED_PITCH_EG_R1, // 0
DEXED_PITCH_EG_R2, // 1
DEXED_PITCH_EG_R3, // 2
DEXED_PITCH_EG_R4, // 3
DEXED_PITCH_EG_L1, // 4
DEXED_PITCH_EG_L2, // 5
DEXED_PITCH_EG_L3, // 6
DEXED_PITCH_EG_L4, // 7
DEXED_ALGORITHM, // 8
DEXED_FEEDBACK, // 9
DEXED_OSC_KEY_SYNC, // 10
DEXED_LFO_SPEED, // 11
DEXED_LFO_DELAY, // 12
DEXED_LFO_PITCH_MOD_DEP, // 13
DEXED_LFO_AMP_MOD_DEP, // 14
DEXED_LFO_SYNC, // 15
DEXED_LFO_WAVE, // 16
DEXED_LFO_PITCH_MOD_SENS, // 17
DEXED_TRANSPOSE, // 18
DEXED_NAME // 19
};
enum ADSR {
ATTACK,
DECAY,
SUSTAIN,
RELEASE
};
enum OPERATORS {
OP1,
OP2,
OP3,
OP4,
OP5,
OP6
};
enum CONTROLLER_ASSIGN {
NONE,
PITCH,
AMP,
PITCH_AMP,
EG,
PITCH_EG,
AMP_EG,
PITCH_AMP_EG
};
enum PORTAMENTO_MODE {
RETAIN,
FOLLOW
};
enum ON_OFF {
OFF,
ON
};
// GLOBALS
//==============================================================================
class Dexed
{
public:
Dexed(uint8_t maxnotes, int rate);
~Dexed();
// Global methods
void activate(void);
void deactivate(void);
bool getMonoMode(void);
void setMonoMode(bool mode);
void setRefreshMode(bool mode);
void setMaxNotes(uint8_t n);
uint8_t getMaxNotes(void);
void doRefreshVoice(void);
void setOPAll(uint8_t ops);
bool decodeVoice(uint8_t* data, uint8_t* encoded_data);
bool encodeVoice(uint8_t* encoded_data);
bool getVoiceData(uint8_t* data_copy);
void setVoiceDataElement(uint8_t address, uint8_t value);
uint8_t getVoiceDataElement(uint8_t address);
void loadInitVoice(void);
void loadVoiceParameters(uint8_t* data);
uint8_t getNumNotesPlaying(void);
uint32_t getXRun(void);
uint16_t getRenderTimeMax(void);
void resetRenderTimeMax(void);
void ControllersRefresh(void);
// Sound methods
void keyup(int16_t pitch);
void keydown(int16_t pitch, uint8_t velo);
void setSustain(bool sustain);
bool getSustain(void);
void panic(void);
void notesOff(void);
void resetControllers(void);
void setMasterTune(int8_t mastertune);
int8_t getMasterTune(void);
void setPortamentoMode(uint8_t portamento_mode, uint8_t portamento_glissando, uint8_t portamento_time);
void setPBController(uint8_t pb_range, uint8_t pb_step);
void setMWController(uint8_t mw_range, uint8_t mw_assign, uint8_t mw_mode);
void setFCController(uint8_t fc_range, uint8_t fc_assign, uint8_t fc_mode);
void setBCController(uint8_t bc_range, uint8_t bc_assign, uint8_t bc_mode);
void setATController(uint8_t at_range, uint8_t at_assign, uint8_t at_mode);
void setModWheel(uint8_t value);
uint8_t getModWheel(void);
void setBreathController(uint8_t value);
uint8_t getBreathController(void);
void setFootController(uint8_t value);
uint8_t getFootController(void);
void setAftertouch(uint8_t value);
uint8_t getAftertouch(void);
void setPitchbend(int16_t value);
int16_t getPitchbend(void);
void setPitchbendRange(uint8_t range);
uint8_t getPitchbendRange(void);
void setPitchbendStep(uint8_t step);
uint8_t getPitchbendStep(void);
void setModWheelRange(uint8_t range);
uint8_t getModWheelRange(void);
void setModWheelTarget(uint8_t target);
uint8_t getModWheelTarget(void);
void setFootControllerRange(uint8_t range);
uint8_t getFootControllerRange(void);
void setFootControllerTarget(uint8_t target);
uint8_t getFootControllerTarget(void);
void setBreathControllerRange(uint8_t range);
uint8_t getBreathControllerRange(void);
void setBreathControllerTarget(uint8_t target);
uint8_t getBreathControllerTarget(void);
void setAftertouchRange(uint8_t range);
uint8_t getAftertouchRange(void);
void setAftertouchTarget(uint8_t target);
uint8_t getAftertouchTarget(void);
void setFilterCutoff(float cutoff);
float getFilterCutoff(void);
void setFilterResonance(float resonance);
float getFilterResonance(void);
void setGain(float gain);
float getGain(void);
// Voice configuration methods
void setOPRateAll(uint8_t rate);
void setOPLevelAll(uint8_t level);
void setOPRateAllCarrier(uint8_t step, uint8_t rate);
void setOPLevelAllCarrier(uint8_t step, uint8_t level);
void setOPRateAllModulator(uint8_t step, uint8_t rate);
void setOPLevelAllModulator(uint8_t step, uint8_t level);
void setOPRate(uint8_t op, uint8_t step, uint8_t rate);
uint8_t getOPRate(uint8_t op, uint8_t step);
void setOPLevel(uint8_t op, uint8_t step, uint8_t level);
uint8_t getOPLevel(uint8_t op, uint8_t step);
void setOPKeyboardLevelScalingBreakPoint(uint8_t op, uint8_t level);
uint8_t getOPKeyboardLevelScalingBreakPoint(uint8_t op);
void setOPKeyboardLevelScalingDepthLeft(uint8_t op, uint8_t depth);
uint8_t getOPKeyboardLevelScalingDepthLeft(uint8_t op);
void setOPKeyboardLevelScalingDepthRight(uint8_t op, uint8_t depth);
uint8_t getOPKeyboardLevelScalingDepthRight(uint8_t op);
void setOPKeyboardLevelScalingCurveLeft(uint8_t op, uint8_t curve);
uint8_t getOPKeyboardLevelScalingCurveLeft(uint8_t op);
void setOPKeyboardLevelScalingCurveRight(uint8_t op, uint8_t curve);
uint8_t getOPKeyboardLevelScalingCurveRight(uint8_t op);
void setOPKeyboardRateScale(uint8_t op, uint8_t scale);
uint8_t getOPKeyboardRateScale(uint8_t op);
void setOPAmpModulationSensity(uint8_t op, uint8_t sensitivity);
uint8_t getOPAmpModulationSensity(uint8_t op);
void setOPKeyboardVelocitySensity(uint8_t op, uint8_t sensitivity);
uint8_t getOPKeyboardVelocitySensity(uint8_t op);
void setOPOutputLevel(uint8_t op, uint8_t level);
uint8_t getOPOutputLevel(uint8_t op);
void setOPMode(uint8_t op, uint8_t mode);
uint8_t getOPMode(uint8_t op);
void setOPFrequencyCoarse(uint8_t op, uint8_t frq_coarse);
uint8_t getOPFrequencyCoarse(uint8_t op);
void setOPFrequencyFine(uint8_t op, uint8_t frq_fine);
uint8_t getOPFrequencyFine(uint8_t op);
void setOPDetune(uint8_t op, uint8_t detune);
uint8_t getOPDetune(uint8_t op);
void setPitchRate(uint8_t step, uint8_t rate);
uint8_t getPitchRate(uint8_t step);
void setPitchLevel(uint8_t step, uint8_t level);
uint8_t getPitchLevel(uint8_t step);
void setAlgorithm(uint8_t algorithm);
uint8_t getAlgorithm(void);
void setFeedback(uint8_t feedback);
uint8_t getFeedback(void);
void setOscillatorSync(bool sync);
bool getOscillatorSync(void);
void setLFOSpeed(uint8_t speed);
uint8_t getLFOSpeed(void);
void setLFODelay(uint8_t delay);
uint8_t getLFODelay(void);
void setLFOPitchModulationDepth(uint8_t depth);
uint8_t getLFOPitchModulationDepth(void);
void setLFOAmpModulationDepth(uint8_t delay);
uint8_t getLFOAmpModulationDepth(void);
void setLFOSync(bool sync);
bool getLFOSync(void);
void setLFOWaveform(uint8_t waveform);
uint8_t getLFOWaveform(void);
void setLFOPitchModulationSensitivity(uint8_t sensitivity);
uint8_t getLFOPitchModulationSensitivity(void);
void setTranspose(uint8_t transpose);
uint8_t getTranspose(void);
void setName(char* name);
void getName(char* buffer);
ProcessorVoice* voices;
protected:
uint8_t init_voice[NUM_VOICE_PARAMETERS] = {
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, // OP6 eg_rate_1-4, level_1-4, kbd_lev_scl_brk_pt, kbd_lev_scl_lft_depth, kbd_lev_scl_rht_depth, kbd_lev_scl_lft_curve, kbd_lev_scl_rht_curve, kbd_rate_scaling, amp_mod_sensitivity, key_vel_sensitivity, operator_output_level, osc_mode, osc_freq_coarse, osc_freq_fine, osc_detune
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, // OP5
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, // OP4
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, // OP4
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 00, 00, 01, 00, 00, // OP4
99, 99, 99, 99, 99, 99, 99, 00, 33, 00, 00, 00, 00, 00, 00, 00, 99, 00, 01, 00, 00, // OP4
99, 99, 99, 99, 50, 50, 50, 50, // 4 * pitch EG rates, 4 * pitch EG level
01, 00, 01, // algorithm, feedback, osc sync
35, 00, 00, 00, 01, 00, // lfo speed, lfo delay, lfo pitch_mod_depth, lfo_amp_mod_depth, lfo_sync, lfo_waveform
03, 48, // pitch_mod_sensitivity, transpose
73, 78, 73, 84, 32, 86, 79, 73, 67, 69 // 10 * char for name ("INIT VOICE")
};
uint8_t data[NUM_VOICE_PARAMETERS];
uint8_t max_notes;
PluginFx fx;
Controllers controllers;
int lastKeyDown;
uint32_t xrun;
uint16_t render_time_max;
int16_t currentNote;
bool sustain;
float vuSignal;
bool monoMode;
bool refreshMode;
bool refreshVoice;
uint8_t engineType;
VoiceStatus voiceStatus;
Lfo lfo;
FmCore* engineMsfa;
void getSamples(uint16_t n_samples, int16_t* buffer);
};
#endif

@ -0,0 +1,388 @@
/*
Copyright 2016-2017 Pascal Gauthier.
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include <math.h>
#include <stdlib.h>
#include "synth.h"
#include "freqlut.h"
#include "exp2.h"
#include "controllers.h"
#include "dx7note.h"
#include "porta.h"
//#include <cmath>
const int FEEDBACK_BITDEPTH = 8;
int32_t midinote_to_logfreq(int midinote) {
//const int32_t base = 50857777; // (1 << 24) * (log(440) / log(2) - 69/12)
const int32_t base = 50857777; // (1 << 24) * (LOG_FUNC(440) / LOG_FUNC(2) - 69/12)
const int32_t step = (1 << 24) / 12;
return base + step * midinote;
}
int32_t logfreq_round2semi(int freq) {
const int base = 50857777; // (1 << 24) * (log(440) / log(2) - 69/12)
const int step = (1 << 24) / 12;
const int rem = (freq - base) % step;
return freq - rem;
}
const int32_t coarsemul[] = {
-16777216, 0, 16777216, 26591258, 33554432, 38955489, 43368474, 47099600,
50331648, 53182516, 55732705, 58039632, 60145690, 62083076, 63876816,
65546747, 67108864, 68576247, 69959732, 71268397, 72509921, 73690858,
74816848, 75892776, 76922906, 77910978, 78860292, 79773775, 80654032,
81503396, 82323963, 83117622
};
int32_t osc_freq(int midinote, int mode, int coarse, int fine, int detune) {
// TODO: pitch randomization
int32_t logfreq;
if (mode == 0) {
logfreq = midinote_to_logfreq(midinote);
// could use more precision, closer enough for now. those numbers comes from my DX7
//FRAC_NUM detuneRatio = 0.0209 * exp(-0.396 * (((float)logfreq) / (1 << 24))) / 7;
FRAC_NUM detuneRatio = 0.0209 * EXP_FUNC(-0.396 * (((float)logfreq) / (1 << 24))) / 7;
logfreq += detuneRatio * logfreq * (detune - 7);
logfreq += coarsemul[coarse & 31];
if (fine) {
// (1 << 24) / log(2)
//logfreq += (int32_t)floor(24204406.323123 * log(1 + 0.01 * fine) + 0.5);
logfreq += (int32_t)floor(24204406.323123 * LOG_FUNC(1 + 0.01 * fine) + 0.5);
}
// // This was measured at 7.213Hz per count at 9600Hz, but the exact
// // value is somewhat dependent on midinote. Close enough for now.
// //logfreq += 12606 * (detune -7);
} else {
// ((1 << 24) * log(10) / log(2) * .01) << 3
logfreq = (4458616 * ((coarse & 3) * 100 + fine)) >> 3;
logfreq += detune > 7 ? 13457 * (detune - 7) : 0;
}
return logfreq;
}
const uint8_t velocity_data[64] = {
0, 70, 86, 97, 106, 114, 121, 126, 132, 138, 142, 148, 152, 156, 160, 163,
166, 170, 173, 174, 178, 181, 184, 186, 189, 190, 194, 196, 198, 200, 202,
205, 206, 209, 211, 214, 216, 218, 220, 222, 224, 225, 227, 229, 230, 232,
233, 235, 237, 238, 240, 241, 242, 243, 244, 246, 246, 248, 249, 250, 251,
252, 253, 254
};
// See "velocity" section of notes. Returns velocity delta in microsteps.
int ScaleVelocity(int velocity, int sensitivity) {
int clamped_vel = max(0, min(127, velocity));
int vel_value = velocity_data[clamped_vel >> 1] - 239;
int scaled_vel = ((sensitivity * vel_value + 7) >> 3) << 4;
return scaled_vel;
}
int ScaleRate(int midinote, int sensitivity) {
int x = min(31, max(0, midinote / 3 - 7));
int qratedelta = (sensitivity * x) >> 3;
#ifdef SUPER_PRECISE
int rem = x & 7;
if (sensitivity == 3 && rem == 3) {
qratedelta -= 1;
} else if (sensitivity == 7 && rem > 0 && rem < 4) {
qratedelta += 1;
}
#endif
return qratedelta;
}
const uint8_t exp_scale_data[] = {
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 14, 16, 19, 23, 27, 33, 39, 47, 56, 66,
80, 94, 110, 126, 142, 158, 174, 190, 206, 222, 238, 250
};
int ScaleCurve(int group, int depth, int curve) {
int scale;
if (curve == 0 || curve == 3) {
// linear
scale = (group * depth * 329) >> 12;
} else {
// exponential
int n_scale_data = sizeof(exp_scale_data);
int raw_exp = exp_scale_data[min(group, n_scale_data - 1)];
scale = (raw_exp * depth * 329) >> 15;
}
if (curve < 2) {
scale = -scale;
}
return scale;
}
int ScaleLevel(int midinote, int break_pt, int left_depth, int right_depth,
int left_curve, int right_curve) {
int offset = midinote - break_pt - 17;
if (offset >= 0) {
return ScaleCurve((offset + 1) / 3, right_depth, right_curve);
} else {
return ScaleCurve(-(offset - 1) / 3, left_depth, left_curve);
}
}
static const uint8_t pitchmodsenstab[] = {
0, 10, 20, 33, 55, 92, 153, 255
};
// 0, 66, 109, 255
static const uint32_t ampmodsenstab[] = {
0, 4342338, 7171437, 16777216
};
Dx7Note::Dx7Note() {
for (int op = 0; op < 6; op++) {
params_[op].phase = 0;
params_[op].gain_out = 0;
}
}
//void Dx7Note::init(const uint8_t patch[156], int midinote, int velocity) {
void Dx7Note::init(const uint8_t patch[156], int midinote, int velocity, int srcnote, int porta, const Controllers *ctrls) {
int rates[4];
int levels[4];
for (int op = 0; op < 6; op++) {
int off = op * 21;
for (int i = 0; i < 4; i++) {
rates[i] = patch[off + i];
levels[i] = patch[off + 4 + i];
}
int outlevel = patch[off + 16];
outlevel = Env::scaleoutlevel(outlevel);
int level_scaling = ScaleLevel(midinote, patch[off + 8], patch[off + 9],
patch[off + 10], patch[off + 11], patch[off + 12]);
outlevel += level_scaling;
outlevel = min(127, outlevel);
outlevel = outlevel << 5;
outlevel += ScaleVelocity(velocity, patch[off + 15]);
outlevel = max(0, outlevel);
int rate_scaling = ScaleRate(midinote, patch[off + 13]);
env_[op].init(rates, levels, outlevel, rate_scaling);
int mode = patch[off + 17];
int coarse = patch[off + 18];
int fine = patch[off + 19];
int detune = patch[off + 20];
int32_t freq = osc_freq(midinote, mode, coarse, fine, detune);
opMode[op] = mode;
basepitch_[op] = freq;
porta_curpitch_[op] = freq;
ampmodsens_[op] = ampmodsenstab[patch[off + 14] & 3];
if (porta >= 0)
porta_curpitch_[op] = osc_freq(srcnote, mode, coarse, fine, detune);
}
for (int i = 0; i < 4; i++) {
rates[i] = patch[126 + i];
levels[i] = patch[130 + i];
}
pitchenv_.set(rates, levels);
algorithm_ = patch[134];
int feedback = patch[135];
fb_shift_ = feedback != 0 ? FEEDBACK_BITDEPTH - feedback : 16;
pitchmoddepth_ = (patch[139] * 165) >> 6;
pitchmodsens_ = pitchmodsenstab[patch[143] & 7];
ampmoddepth_ = (patch[140] * 165) >> 6;
porta_rateindex_ = (porta < 128) ? porta : 127;
porta_gliss_ = ctrls->values_[kControllerPortamentoGlissando];
}
void Dx7Note::compute(int32_t *buf, int32_t lfo_val, int32_t lfo_delay, const Controllers *ctrls) {
// ==== PITCH ====
uint32_t pmd = pitchmoddepth_ * lfo_delay; // Q32
int32_t senslfo = pitchmodsens_ * (lfo_val - (1 << 23));
int32_t pmod_1 = (((int64_t) pmd) * (int64_t) senslfo) >> 39;
pmod_1 = abs(pmod_1);
int32_t pmod_2 = (int32_t)(((int64_t)ctrls->pitch_mod * (int64_t)senslfo) >> 14);
pmod_2 = abs(pmod_2);
int32_t pitch_mod = max(pmod_1, pmod_2);
pitch_mod = pitchenv_.getsample() + (pitch_mod * (senslfo < 0 ? -1 : 1));
// ---- PITCH BEND ----
int pitchbend = ctrls->values_[kControllerPitch];
int32_t pb = (pitchbend - 0x2000);
if (pb != 0) {
if (ctrls->values_[kControllerPitchStep] == 0) {
pb = ((float) (pb << 11)) * ((float) ctrls->values_[kControllerPitchRange]) / 12.0;
} else {
int stp = 12 / ctrls->values_[kControllerPitchStep];
pb = pb * stp / 8191;
pb = (pb * (8191 / stp)) << 11;
}
}
int32_t pitch_base = pb + ctrls->masterTune;
pitch_mod += pitch_base;
// ==== AMP MOD ====
lfo_val = (1 << 24) - lfo_val;
uint32_t amod_1 = (uint32_t)(((int64_t) ampmoddepth_ * (int64_t) lfo_delay) >> 8); // Q24 :D
amod_1 = (uint32_t)(((int64_t) amod_1 * (int64_t) lfo_val) >> 24);
uint32_t amod_2 = (uint32_t)(((int64_t) ctrls->amp_mod * (int64_t) lfo_val) >> 7); // Q?? :|
uint32_t amd_mod = max(amod_1, amod_2);
// ==== EG AMP MOD ====
uint32_t amod_3 = (ctrls->eg_mod + 1) << 17;
amd_mod = max((1 << 24) - amod_3, amd_mod);
// ==== OP RENDER ====
for (int op = 0; op < 6; op++) {
// if ( ctrls->opSwitch[op] == '0' ) {
if (!(ctrls->opSwitch & (1 << op))) {
env_[op].getsample(); // advance the envelop even if it is not playing
params_[op].level_in = 0;
} else {
//int32_t gain = pow(2, 10 + level * (1.0 / (1 << 24)));
int32_t basepitch = basepitch_[op];
if ( opMode[op] )
params_[op].freq = Freqlut::lookup(basepitch + pitch_base);
else {
if ( porta_rateindex_ >= 0 ) {
basepitch = porta_curpitch_[op];
if ( porta_gliss_ )
basepitch = logfreq_round2semi(basepitch);
}
params_[op].freq = Freqlut::lookup(basepitch + pitch_mod);
}
int32_t level = env_[op].getsample();
if (ampmodsens_[op] != 0) {
uint32_t sensamp = (uint32_t)(((uint64_t) amd_mod) * ((uint64_t) ampmodsens_[op]) >> 24);
// TODO: mehhh.. this needs some real tuning.
//uint32_t pt = exp(((float)sensamp) / 262144 * 0.07 + 12.2);
uint32_t pt = EXP_FUNC(((float)sensamp) / 262144 * 0.07 + 12.2);
uint32_t ldiff = (uint32_t)(((uint64_t)level) * (((uint64_t)pt << 4)) >> 28);
level -= ldiff;
}
params_[op].level_in = level;
}
}
// ==== PORTAMENTO ====
int porta = porta_rateindex_;
if ( porta >= 0 ) {
int32_t rate = Porta::rates[porta];
for (int op = 0; op < 6; op++) {
int32_t cur = porta_curpitch_[op];
int32_t dst = basepitch_[op];
bool going_up = cur < dst;
int32_t newpitch = cur + (going_up ? +rate : -rate);
if ( going_up ? (cur > dst) : (cur < dst) )
newpitch = dst;
porta_curpitch_[op] = newpitch;
}
}
ctrls->core->render(buf, params_, algorithm_, fb_buf_, fb_shift_);
}
void Dx7Note::keyup() {
for (int op = 0; op < 6; op++) {
env_[op].keydown(false);
}
pitchenv_.keydown(false);
}
void Dx7Note::update(const uint8_t patch[156], int midinote, int velocity, int porta, const Controllers *ctrls) {
int rates[4];
int levels[4];
for (int op = 0; op < 6; op++) {
int off = op * 21;
int mode = patch[off + 17];
int coarse = patch[off + 18];
int fine = patch[off + 19];
int detune = patch[off + 20];
int32_t freq = osc_freq(midinote, mode, coarse, fine, detune);
basepitch_[op] = freq;
porta_curpitch_[op] = freq;
ampmodsens_[op] = ampmodsenstab[patch[off + 14] & 3];
opMode[op] = mode;
for (int i = 0; i < 4; i++) {
rates[i] = patch[off + i];
levels[i] = patch[off + 4 + i];
}
int outlevel = patch[off + 16];
outlevel = Env::scaleoutlevel(outlevel);
int level_scaling = ScaleLevel(midinote, patch[off + 8], patch[off + 9],
patch[off + 10], patch[off + 11], patch[off + 12]);
outlevel += level_scaling;
outlevel = min(127, outlevel);
outlevel = outlevel << 5;
outlevel += ScaleVelocity(velocity, patch[off + 15]);
outlevel = max(0, outlevel);
int rate_scaling = ScaleRate(midinote, patch[off + 13]);
env_[op].update(rates, levels, outlevel, rate_scaling);
}
algorithm_ = patch[134];
int feedback = patch[135];
fb_shift_ = feedback != 0 ? FEEDBACK_BITDEPTH - feedback : 16;
pitchmoddepth_ = (patch[139] * 165) >> 6;
pitchmodsens_ = pitchmodsenstab[patch[143] & 7];
ampmoddepth_ = (patch[140] * 165) >> 6;
porta_rateindex_ = (porta < 128) ? porta : 127;
porta_gliss_ = ctrls->values_[kControllerPortamentoGlissando];
}
void Dx7Note::peekVoiceStatus(VoiceStatus &status) {
for (int i = 0; i < 6; i++) {
status.amp[i] = Exp2::lookup(params_[i].level_in - (14 * (1 << 24)));
env_[i].getPosition(&status.ampStep[i]);
}
pitchenv_.getPosition(&status.pitchStep);
}
/**
Used in monophonic mode to transfer voice state from different notes
*/
void Dx7Note::transferState(Dx7Note &src) {
for (int i = 0; i < 6; i++) {
env_[i].transfer(src.env_[i]);
params_[i].gain_out = src.params_[i].gain_out;
params_[i].phase = src.params_[i].phase;
}
}
void Dx7Note::transferSignal(Dx7Note &src) {
for (int i = 0; i < 6; i++) {
params_[i].gain_out = src.params_[i].gain_out;
params_[i].phase = src.params_[i].phase;
}
}
void Dx7Note::transferPortamento(Dx7Note &src) {
for (int i = 0; i < 6; i++) {
porta_curpitch_[i] = src.porta_curpitch_[i];
}
}
void Dx7Note::oscSync() {
for (int i = 0; i < 6; i++) {
params_[i].gain_out = 0;
params_[i].phase = 0;
}
}

@ -0,0 +1,82 @@
/*
Copyright 2016-2017 Pascal Gauthier.
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef SYNTH_DX7NOTE_H_
#define SYNTH_DX7NOTE_H_
// This is the logic to put together a note from the MIDI description
// and run the low-level modules.
// It will continue to evolve a bit, as note-stealing logic, scaling,
// and real-time control of parameters live here.
#include <Arduino.h>
#include "env.h"
#include "pitchenv.h"
#include "fm_core.h"
struct VoiceStatus {
uint32_t amp[6];
char ampStep[6];
char pitchStep;
};
class Dx7Note {
public:
Dx7Note();
void init(const uint8_t patch[156], int midinote, int velocity, int srcnote, int porta, const Controllers *ctrls);
// Note: this _adds_ to the buffer. Interesting question whether it's
// worth it...
void compute(int32_t *buf, int32_t lfo_val, int32_t lfo_delay, const Controllers *ctrls);
void keyup();
// TODO: some way of indicating end-of-note. Maybe should be a return
// value from the compute method? (Having a count return from keyup
// is also tempting, but if there's a dynamic parameter change after
// keyup, that won't work.
// PG:add the update
void update(const uint8_t patch[156], int midinote, int velocity, int porta, const Controllers *ctrls);
void peekVoiceStatus(VoiceStatus &status);
void transferState(Dx7Note& src);
void transferSignal(Dx7Note &src);
void transferPortamento(Dx7Note &src);
void oscSync();
private:
Env env_[6];
FmOpParams params_[6];
PitchEnv pitchenv_;
int32_t basepitch_[6];
int32_t fb_buf_[2];
int32_t fb_shift_;
int32_t ampmodsens_[6];
int32_t opMode[6];
int ampmoddepth_;
int algorithm_;
int pitchmoddepth_;
int pitchmodsens_;
int porta_rateindex_;
int porta_gliss_;
int32_t porta_curpitch_[6];
};
#endif

@ -0,0 +1,190 @@
/*
Copyright 2017 Pascal Gauthier.
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
//using namespace std;
#include <math.h>
#include "synth.h"
#include "env.h"
uint32_t Env::sr_multiplier = (1 << 24);
const int levellut[] = {
0, 5, 9, 13, 17, 20, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 42, 43, 45, 46
};
#ifdef ACCURATE_ENVELOPE
const int statics[] = {
1764000, 1764000, 1411200, 1411200, 1190700, 1014300, 992250,
882000, 705600, 705600, 584325, 507150, 502740, 441000, 418950,
352800, 308700, 286650, 253575, 220500, 220500, 176400, 145530,
145530, 125685, 110250, 110250, 88200, 88200, 74970, 61740,
61740, 55125, 48510, 44100, 37485, 31311, 30870, 27562, 27562,
22050, 18522, 17640, 15435, 14112, 13230, 11025, 9261, 9261, 7717,
6615, 6615, 5512, 5512, 4410, 3969, 3969, 3439, 2866, 2690, 2249,
1984, 1896, 1808, 1411, 1367, 1234, 1146, 926, 837, 837, 705,
573, 573, 529, 441, 441
// and so on, I stopped measuring after R=76 (needs to be double-checked anyway)
};
#endif
void Env::init_sr(double sampleRate) {
sr_multiplier = (44100.0 / sampleRate) * (1 << 24);
}
void Env::init(const int r[4], const int l[4], int ol, int rate_scaling) {
for (int i = 0; i < 4; i++) {
rates_[i] = r[i];
levels_[i] = l[i];
}
outlevel_ = ol;
rate_scaling_ = rate_scaling;
level_ = 0;
down_ = true;
advance(0);
}
int32_t Env::getsample() {
#ifdef ACCURATE_ENVELOPE
if (staticcount_) {
staticcount_ -= _N_;
if (staticcount_ <= 0) {
staticcount_ = 0;
advance(ix_ + 1);
}
}
#endif
if (ix_ < 3 || ((ix_ < 4) && !down_)) {
if (staticcount_) {
;
}
else if (rising_) {
const int jumptarget = 1716;
if (level_ < (jumptarget << 16)) {
level_ = jumptarget << 16;
}
level_ += (((17 << 24) - level_) >> 24) * inc_;
// TODO: should probably be more accurate when inc is large
if (level_ >= targetlevel_) {
level_ = targetlevel_;
advance(ix_ + 1);
}
}
else { // !rising
level_ -= inc_;
if (level_ <= targetlevel_) {
level_ = targetlevel_;
advance(ix_ + 1);
}
}
}
// TODO: this would be a good place to set level to 0 when under threshold
return level_;
}
void Env::keydown(bool d) {
if (down_ != d) {
down_ = d;
advance(d ? 0 : 3);
}
}
int Env::scaleoutlevel(int outlevel) {
return outlevel >= 20 ? 28 + outlevel : levellut[outlevel];
}
void Env::advance(int newix) {
ix_ = newix;
if (ix_ < 4) {
int newlevel = levels_[ix_];
int actuallevel = scaleoutlevel(newlevel) >> 1;
actuallevel = (actuallevel << 6) + outlevel_ - 4256;
actuallevel = actuallevel < 16 ? 16 : actuallevel;
// level here is same as Java impl
targetlevel_ = actuallevel << 16;
rising_ = (targetlevel_ > level_);
// rate
int qrate = (rates_[ix_] * 41) >> 6;
qrate += rate_scaling_;
qrate = min(qrate, 63);
#ifdef ACCURATE_ENVELOPE
if (targetlevel_ == level_ || (ix_ == 0 && newlevel == 0)) {
// approximate number of samples at 44.100 kHz to achieve the time
// empirically gathered using 2 TF1s, could probably use some double-checking
// and cleanup, but it's pretty close for now.
int staticrate = rates_[ix_];
staticrate += rate_scaling_; // needs to be checked, as well, but seems correct
staticrate = min(staticrate, 99);
staticcount_ = staticrate < 77 ? statics[staticrate] : 20 * (99 - staticrate);
if (staticrate < 77 && (ix_ == 0 && newlevel == 0)) {
staticcount_ /= 20; // attack is scaled faster
}
staticcount_ = (int)(((int64_t)staticcount_ * (int64_t)sr_multiplier) >> 24);
}
else {
staticcount_ = 0;
}
#endif
inc_ = (4 + (qrate & 3)) << (2 + LG_N + (qrate >> 2));
// meh, this should be fixed elsewhere
inc_ = (int)(((int64_t)inc_ * (int64_t)sr_multiplier) >> 24);
}
}
void Env::update(const int r[4], const int l[4], int ol, int rate_scaling) {
for (int i = 0; i < 4; i++) {
rates_[i] = r[i];
levels_[i] = l[i];
}
outlevel_ = ol;
rate_scaling_ = rate_scaling;
if ( down_ ) {
// for now we simply reset ourselves at level 3
int newlevel = levels_[2];
int actuallevel = scaleoutlevel(newlevel) >> 1;
actuallevel = (actuallevel << 6) - 4256;
actuallevel = actuallevel < 16 ? 16 : actuallevel;
targetlevel_ = actuallevel << 16;
advance(2);
}
}
void Env::getPosition(char *step) {
*step = ix_;
}
void Env::transfer(Env &src) {
for (int i = 0; i < 4; i++) {
rates_[i] = src.rates_[i];
levels_[i] = src.levels_[i];
}
outlevel_ = src.outlevel_;
rate_scaling_ = src.rate_scaling_;
level_ = src.level_;
targetlevel_ = src.targetlevel_;
rising_ = src.rising_;
ix_ = src.ix_;
down_ = src.down_;
#ifdef ACCURATE_ENVELOPE
staticcount_ = src.staticcount_;
#endif
inc_ = src.inc_;
}

@ -0,0 +1,81 @@
/*
Copyright 2017 Pascal Gauthier.
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef __ENV_H
#define __ENV_H
#include "synth.h"
// DX7 envelope generation
#define ACCURATE_ENVELOPE
class Env {
public:
// The rates and levels arrays are calibrated to match the Dx7 parameters
// (ie, value 0..99). The outlevel parameter is calibrated in microsteps
// (ie units of approx .023 dB), with 99 * 32 = nominal full scale. The
// rate_scaling parameter is in qRate units (ie 0..63).
void init(const int rates[4], const int levels[4], int outlevel,
int rate_scaling);
void update(const int rates[4], const int levels[4], int outlevel,
int rate_scaling);
// Result is in Q24/doubling log format. Also, result is subsampled
// for every N samples.
// A couple more things need to happen for this to be used as a gain
// value. First, the # of outputs scaling needs to be applied. Also,
// modulation.
// Then, of course, log to linear.
int32_t getsample();
void keydown(bool down);
static int scaleoutlevel(int outlevel);
void getPosition(char *step);
static void init_sr(double sample_rate);
void transfer(Env &src);
private:
// PG: This code is normalized to 44100, need to put a multiplier
// if we are not using 44100.
static uint32_t sr_multiplier;
int rates_[4];
int levels_[4];
int outlevel_;
int rate_scaling_;
// Level is stored so that 2^24 is one doubling, ie 16 more bits than
// the DX7 itself (fraction is stored in level rather than separate
// counter)
int32_t level_;
int targetlevel_;
bool rising_;
int ix_;
int inc_;
#ifdef ACCURATE_ENVELOPE
int staticcount_;
#endif
bool down_;
void advance(int newix);
};
#endif

@ -0,0 +1,70 @@
/*
* Copyright 2013 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define _USE_MATH_DEFINES
#include <math.h>
#include "synth.h"
#include "exp2.h"
//#include <stdio.h>
#ifdef _MSC_VER
#define exp2(arg) pow(2.0, arg)
#endif
int32_t exp2tab[EXP2_N_SAMPLES << 1];
void Exp2::init() {
FRAC_NUM inc = exp2(1.0 / EXP2_N_SAMPLES);
FRAC_NUM y = 1 << 30;
for (int i = 0; i < EXP2_N_SAMPLES; i++) {
exp2tab[(i << 1) + 1] = (int32_t)floor(y + 0.5);
y *= inc;
}
for (int i = 0; i < EXP2_N_SAMPLES - 1; i++) {
exp2tab[i << 1] = exp2tab[(i << 1) + 3] - exp2tab[(i << 1) + 1];
}
exp2tab[(EXP2_N_SAMPLES << 1) - 2] = (1U << 31) - exp2tab[(EXP2_N_SAMPLES << 1) - 1];
}
int32_t tanhtab[TANH_N_SAMPLES << 1];
static FRAC_NUM dtanh(FRAC_NUM y) {
return 1 - y * y;
}
void Tanh::init() {
FRAC_NUM step = 4.0 / TANH_N_SAMPLES;
FRAC_NUM y = 0;
for (int i = 0; i < TANH_N_SAMPLES; i++) {
tanhtab[(i << 1) + 1] = (1 << 24) * y + 0.5;
//printf("%d\n", tanhtab[(i << 1) + 1]);
// Use a basic 4th order Runge-Kutte to compute tanh from its
// differential equation.
FRAC_NUM k1 = dtanh(y);
FRAC_NUM k2 = dtanh(y + 0.5 * step * k1);
FRAC_NUM k3 = dtanh(y + 0.5 * step * k2);
FRAC_NUM k4 = dtanh(y + step * k3);
FRAC_NUM dy = (step / 6) * (k1 + k4 + 2 * (k2 + k3));
y += dy;
}
for (int i = 0; i < TANH_N_SAMPLES - 1; i++) {
tanhtab[i << 1] = tanhtab[(i << 1) + 3] - tanhtab[(i << 1) + 1];
}
int32_t lasty = (1 << 24) * y + 0.5;
tanhtab[(TANH_N_SAMPLES << 1) - 2] = lasty - tanhtab[(TANH_N_SAMPLES << 1) - 1];
}

@ -0,0 +1,80 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
class Exp2 {
public:
Exp2();
static void init();
// Q24 in, Q24 out
static int32_t lookup(int32_t x);
};
#define EXP2_LG_N_SAMPLES 10
#define EXP2_N_SAMPLES (1 << EXP2_LG_N_SAMPLES)
#define EXP2_INLINE
extern int32_t exp2tab[EXP2_N_SAMPLES << 1];
#ifdef EXP2_INLINE
inline
int32_t Exp2::lookup(int32_t x) {
const int SHIFT = 24 - EXP2_LG_N_SAMPLES;
int lowbits = x & ((1 << SHIFT) - 1);
int x_int = (x >> (SHIFT - 1)) & ((EXP2_N_SAMPLES - 1) << 1);
int dy = exp2tab[x_int];
int y0 = exp2tab[x_int + 1];
int y = y0 + (((int64_t)dy * (int64_t)lowbits) >> SHIFT);
return y >> (6 - (x >> 24));
}
#endif
class Tanh {
public:
static void init();
// Q24 in, Q24 out
static int32_t lookup(int32_t x);
};
#define TANH_LG_N_SAMPLES 10
#define TANH_N_SAMPLES (1 << TANH_LG_N_SAMPLES)
extern int32_t tanhtab[TANH_N_SAMPLES << 1];
inline
int32_t Tanh::lookup(int32_t x) {
int32_t signum = x >> 31;
x ^= signum;
if (x >= (4 << 24)) {
if (x >= (17 << 23)) {
return signum ^ (1 << 24);
}
int32_t sx = ((int64_t) - 48408812 * (int64_t)x) >> 24;
return signum ^ ((1 << 24) - 2 * Exp2::lookup(sx));
} else {
const int SHIFT = 26 - TANH_LG_N_SAMPLES;
int lowbits = x & ((1 << SHIFT) - 1);
int x_int = (x >> (SHIFT - 1)) & ((TANH_N_SAMPLES - 1) << 1);
int dy = tanhtab[x_int];
int y0 = tanhtab[x_int + 1];
int y = y0 + (((int64_t)dy * (int64_t)lowbits) >> SHIFT);
return y ^ signum;
}
}

@ -0,0 +1,50 @@
/* ----------------------------------------------------------------------
* https://community.arm.com/tools/f/discussions/4292/cmsis-dsp-new-functionality-proposal/22621#22621
* Fast approximation to the log2() function. It uses a two step
* process. First, it decomposes the floating-point number into
* a fractional component F and an exponent E. The fraction component
* is used in a polynomial approximation and then the exponent added
* to the result. A 3rd order polynomial is used and the result
* when computing db20() is accurate to 7.984884e-003 dB.
** ------------------------------------------------------------------- */
static float log2f_approx_coeff[4] = {1.23149591368684f, -4.11852516267426f, 6.02197014179219f, -3.13396450166353f};
static float log2f_approx(float X)
{
float *C = &log2f_approx_coeff[0];
float Y;
float F;
int E;
// This is the approximation to log2()
F = frexpf(fabsf(X), &E);
// Y = C[0]*F*F*F + C[1]*F*F + C[2]*F + C[3] + E;
Y = *C++;
Y *= F;
Y += (*C++);
Y *= F;
Y += (*C++);
Y *= F;
Y += (*C++);
Y += E;
return(Y);
}
// https://codingforspeed.com/using-faster-exponential-approximation/
inline float expf_approx(float x) {
x = 1.0f + x / 1024;
x *= x; x *= x; x *= x; x *= x;
x *= x; x *= x; x *= x; x *= x;
x *= x; x *= x;
return x;
}
inline float unitToDb(float unit) {
return 6.02f * log2f_approx(unit);
}
inline float dbToUnit(float db) {
return expf_approx(db * 2.302585092994046f * 0.05f);
}

@ -0,0 +1,144 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
//using namespace std;
#include "synth.h"
#include "exp2.h"
#include "fm_op_kernel.h"
#include "fm_core.h"
const FmAlgorithm FmCore::algorithms[32] = {
{ { 0xc1, 0x11, 0x11, 0x14, 0x01, 0x14 } }, // 1
{ { 0x01, 0x11, 0x11, 0x14, 0xc1, 0x14 } }, // 2
{ { 0xc1, 0x11, 0x14, 0x01, 0x11, 0x14 } }, // 3
{ { 0xc1, 0x11, 0x94, 0x01, 0x11, 0x14 } }, // 4
{ { 0xc1, 0x14, 0x01, 0x14, 0x01, 0x14 } }, // 5
{ { 0xc1, 0x94, 0x01, 0x14, 0x01, 0x14 } }, // 6
{ { 0xc1, 0x11, 0x05, 0x14, 0x01, 0x14 } }, // 7
{ { 0x01, 0x11, 0xc5, 0x14, 0x01, 0x14 } }, // 8
{ { 0x01, 0x11, 0x05, 0x14, 0xc1, 0x14 } }, // 9
{ { 0x01, 0x05, 0x14, 0xc1, 0x11, 0x14 } }, // 10
{ { 0xc1, 0x05, 0x14, 0x01, 0x11, 0x14 } }, // 11
{ { 0x01, 0x05, 0x05, 0x14, 0xc1, 0x14 } }, // 12
{ { 0xc1, 0x05, 0x05, 0x14, 0x01, 0x14 } }, // 13
{ { 0xc1, 0x05, 0x11, 0x14, 0x01, 0x14 } }, // 14
{ { 0x01, 0x05, 0x11, 0x14, 0xc1, 0x14 } }, // 15
{ { 0xc1, 0x11, 0x02, 0x25, 0x05, 0x14 } }, // 16
{ { 0x01, 0x11, 0x02, 0x25, 0xc5, 0x14 } }, // 17
{ { 0x01, 0x11, 0x11, 0xc5, 0x05, 0x14 } }, // 18
{ { 0xc1, 0x14, 0x14, 0x01, 0x11, 0x14 } }, // 19
{ { 0x01, 0x05, 0x14, 0xc1, 0x14, 0x14 } }, // 20
{ { 0x01, 0x14, 0x14, 0xc1, 0x14, 0x14 } }, // 21
{ { 0xc1, 0x14, 0x14, 0x14, 0x01, 0x14 } }, // 22
{ { 0xc1, 0x14, 0x14, 0x01, 0x14, 0x04 } }, // 23
{ { 0xc1, 0x14, 0x14, 0x14, 0x04, 0x04 } }, // 24
{ { 0xc1, 0x14, 0x14, 0x04, 0x04, 0x04 } }, // 25
{ { 0xc1, 0x05, 0x14, 0x01, 0x14, 0x04 } }, // 26
{ { 0x01, 0x05, 0x14, 0xc1, 0x14, 0x04 } }, // 27
{ { 0x04, 0xc1, 0x11, 0x14, 0x01, 0x14 } }, // 28
{ { 0xc1, 0x14, 0x01, 0x14, 0x04, 0x04 } }, // 29
{ { 0x04, 0xc1, 0x11, 0x14, 0x04, 0x04 } }, // 30
{ { 0xc1, 0x14, 0x04, 0x04, 0x04, 0x04 } }, // 31
{ { 0xc4, 0x04, 0x04, 0x04, 0x04, 0x04 } }, // 32
};
int n_out(const FmAlgorithm &alg) {
int count = 0;
for (int i = 0; i < 6; i++) {
if ((alg.ops[i] & 7) == OUT_BUS_ADD) count++;
}
return count;
}
uint8_t FmCore::get_carrier_operators(uint8_t algorithm)
{
uint8_t op_out = 0;
FmAlgorithm alg = algorithms[algorithm];
for (uint8_t i = 0; i < 6; i++)
{
if ((alg.ops[i]&OUT_BUS_ADD) == OUT_BUS_ADD)
op_out |= 1 << i;
}
return op_out;
}
void FmCore::dump() {
#ifdef VERBOSE
for (int i = 0; i < 32; i++) {
cout << (i + 1) << ":";
const FmAlgorithm &alg = algorithms[i];
for (int j = 0; j < 6; j++) {
int flags = alg.ops[j];
cout << " ";
if (flags & FB_IN) cout << "[";
cout << (flags & IN_BUS_ONE ? "1" : flags & IN_BUS_TWO ? "2" : "0") << "->";
cout << (flags & OUT_BUS_ONE ? "1" : flags & OUT_BUS_TWO ? "2" : "0");
if (flags & OUT_BUS_ADD) cout << "+";
//cout << alg.ops[j].in << "->" << alg.ops[j].out;
if (flags & FB_OUT) cout << "]";
}
cout << " " << n_out(alg);
cout << endl;
}
#endif
}
void FmCore::render(int32_t *output, FmOpParams *params, int algorithm, int32_t *fb_buf, int feedback_shift) {
const int kLevelThresh = 1120;
const FmAlgorithm alg = algorithms[algorithm];
bool has_contents[3] = { true, false, false };
for (int op = 0; op < 6; op++) {
int flags = alg.ops[op];
bool add = (flags & OUT_BUS_ADD) != 0;
FmOpParams &param = params[op];
int inbus = (flags >> 4) & 3;
int outbus = flags & 3;
int32_t *outptr = (outbus == 0) ? output : buf_[outbus - 1].get();
int32_t gain1 = param.gain_out;
int32_t gain2 = Exp2::lookup(param.level_in - (14 * (1 << 24)));
param.gain_out = gain2;
if (gain1 >= kLevelThresh || gain2 >= kLevelThresh) {
if (!has_contents[outbus]) {
add = false;
}
if (inbus == 0 || !has_contents[inbus]) {
// todo: more than one op in a feedback loop
if ((flags & 0xc0) == 0xc0 && feedback_shift < 16) {
// cout << op << " fb " << inbus << outbus << add << endl;
FmOpKernel::compute_fb(outptr, param.phase, param.freq,
gain1, gain2,
fb_buf, feedback_shift, add);
} else {
// cout << op << " pure " << inbus << outbus << add << endl;
FmOpKernel::compute_pure(outptr, param.phase, param.freq,
gain1, gain2, add);
}
} else {
// cout << op << " normal " << inbus << outbus << " " << param.freq << add << endl;
FmOpKernel::compute(outptr, buf_[inbus - 1].get(),
param.phase, param.freq, gain1, gain2, add);
}
has_contents[outbus] = true;
} else if (!add) {
has_contents[outbus] = false;
}
param.phase += param.freq << LG_N;
}
}

@ -0,0 +1,58 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef __FM_CORE_H
#define __FM_CORE_H
#include <Arduino.h>
#include "aligned_buf.h"
#include "fm_op_kernel.h"
#include "synth.h"
#include "controllers.h"
class FmOperatorInfo {
public:
int in;
int out;
};
enum FmOperatorFlags {
OUT_BUS_ONE = 1 << 0,
OUT_BUS_TWO = 1 << 1,
OUT_BUS_ADD = 1 << 2,
IN_BUS_ONE = 1 << 4,
IN_BUS_TWO = 1 << 5,
FB_IN = 1 << 6,
FB_OUT = 1 << 7
};
class FmAlgorithm {
public:
int ops[6];
};
class FmCore {
public:
virtual ~FmCore() {};
static void dump();
uint8_t get_carrier_operators(uint8_t algorithm);
virtual void render(int32_t *output, FmOpParams *params, int algorithm, int32_t *fb_buf, int feedback_gain);
protected:
AlignedBuf<int32_t, _N_>buf_[2];
const static FmAlgorithm algorithms[32];
};
#endif

@ -0,0 +1,280 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include <math.h>
#include <cstdlib>
#ifdef HAVE_NEON
#include <cpu-features.h>
#endif
#include "synth.h"
#include "sin.h"
#include "fm_op_kernel.h"
#ifdef HAVE_NEON
static bool hasNeon() {
return true;
return (android_getCpuFeatures() & ANDROID_CPU_ARM_FEATURE_NEON) != 0;
}
extern "C"
void neon_fm_kernel(const int *in, const int *busin, int *out, int count,
int32_t phase0, int32_t freq, int32_t gain1, int32_t dgain);
#else
static bool hasNeon() {
return false;
}
#endif
void FmOpKernel::compute(int32_t *output, const int32_t *input,
int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
if (hasNeon()) {
#ifdef HAVE_NEON
neon_fm_kernel(input, add ? output : zeros, output, _N_,
phase0, freq, gain, dgain);
#endif
} else {
if (add) {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t y = Sin::lookup(phase + input[i]);
int32_t y1 = ((int64_t)y * (int64_t)gain) >> 24;
output[i] += y1;
phase += freq;
}
} else {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t y = Sin::lookup(phase + input[i]);
int32_t y1 = ((int64_t)y * (int64_t)gain) >> 24;
output[i] = y1;
phase += freq;
}
}
}
}
void FmOpKernel::compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
if (hasNeon()) {
#ifdef HAVE_NEON
neon_fm_kernel(zeros, add ? output : zeros, output, _N_,
phase0, freq, gain, dgain);
#endif
} else {
if (add) {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t y = Sin::lookup(phase);
int32_t y1 = ((int64_t)y * (int64_t)gain) >> 24;
output[i] += y1;
phase += freq;
}
} else {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t y = Sin::lookup(phase);
int32_t y1 = ((int64_t)y * (int64_t)gain) >> 24;
output[i] = y1;
phase += freq;
}
}
}
}
#define noDOUBLE_ACCURACY
#define HIGH_ACCURACY
void FmOpKernel::compute_fb(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2,
int32_t *fb_buf, int fb_shift, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
int32_t y0 = fb_buf[0];
int32_t y = fb_buf[1];
if (add) {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t scaled_fb = (y0 + y) >> (fb_shift + 1);
y0 = y;
y = Sin::lookup(phase + scaled_fb);
y = ((int64_t)y * (int64_t)gain) >> 24;
output[i] += y;
phase += freq;
}
} else {
for (int i = 0; i < _N_; i++) {
gain += dgain;
int32_t scaled_fb = (y0 + y) >> (fb_shift + 1);
y0 = y;
y = Sin::lookup(phase + scaled_fb);
y = ((int64_t)y * (int64_t)gain) >> 24;
output[i] = y;
phase += freq;
}
}
fb_buf[0] = y0;
fb_buf[1] = y;
}
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////
// Experimental sine wave generators below
#if 0
// Results: accuracy 64.3 mean, 170 worst case
// high accuracy: 5.0 mean, 49 worst case
void FmOpKernel::compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
#ifdef HIGH_ACCURACY
int32_t u = Sin::compute10(phase << 6);
u = ((int64_t)u * gain) >> 30;
int32_t v = Sin::compute10((phase << 6) + (1 << 28)); // quarter cycle
v = ((int64_t)v * gain) >> 30;
int32_t s = Sin::compute10(freq << 6);
int32_t c = Sin::compute10((freq << 6) + (1 << 28));
#else
int32_t u = Sin::compute(phase);
u = ((int64_t)u * gain) >> 24;
int32_t v = Sin::compute(phase + (1 << 22)); // quarter cycle
v = ((int64_t)v * gain) >> 24;
int32_t s = Sin::compute(freq) << 6;
int32_t c = Sin::compute(freq + (1 << 22)) << 6;
#endif
for (int i = 0; i < _N_; i++) {
output[i] = u;
int32_t t = ((int64_t)v * (int64_t)c - (int64_t)u * (int64_t)s) >> 30;
u = ((int64_t)u * (int64_t)c + (int64_t)v * (int64_t)s) >> 30;
v = t;
}
}
#endif
#if 0
// Results: accuracy 392.3 mean, 15190 worst case (near freq = 0.5)
// for freq < 0.25, 275.2 mean, 716 worst
// high accuracy: 57.4 mean, 7559 worst
// freq < 0.25: 17.9 mean, 78 worst
void FmOpKernel::compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
#ifdef HIGH_ACCURACY
int32_t u = floor(gain * sin(phase * (M_PI / (1 << 23))) + 0.5);
int32_t v = floor(gain * cos((phase - freq * 0.5) * (M_PI / (1 << 23))) + 0.5);
int32_t a = floor((1 << 25) * sin(freq * (M_PI / (1 << 24))) + 0.5);
#else
int32_t u = Sin::compute(phase);
u = ((int64_t)u * gain) >> 24;
int32_t v = Sin::compute(phase + (1 << 22) - (freq >> 1));
v = ((int64_t)v * gain) >> 24;
int32_t a = Sin::compute(freq >> 1) << 1;
#endif
for (int i = 0; i < _N_; i++) {
output[i] = u;
v -= ((int64_t)a * (int64_t)u) >> 24;
u += ((int64_t)a * (int64_t)v) >> 24;
}
}
#endif
#if 0
// Results: accuracy 370.0 mean, 15480 worst case (near freq = 0.5)
// with FRAC_NUM accuracy initialization: mean 1.55, worst 58 (near freq = 0)
// with high accuracy: mean 4.2, worst 292 (near freq = 0.5)
void FmOpKernel::compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
#ifdef DOUBLE_ACCURACY
int32_t u = floor((1 << 30) * sin(phase * (M_PI / (1 << 23))) + 0.5);
FRAC_NUM a_d = sin(freq * (M_PI / (1 << 24)));
int32_t v = floor((1LL << 31) * a_d * cos((phase - freq * 0.5) *
(M_PI / (1 << 23))) + 0.5);
int32_t aa = floor((1LL << 31) * a_d * a_d + 0.5);
#else
#ifdef HIGH_ACCURACY
int32_t u = Sin::compute10(phase << 6);
int32_t v = Sin::compute10((phase << 6) + (1 << 28) - (freq << 5));
int32_t a = Sin::compute10(freq << 5);
v = ((int64_t)v * (int64_t)a) >> 29;
int32_t aa = ((int64_t)a * (int64_t)a) >> 29;
#else
int32_t u = Sin::compute(phase) << 6;
int32_t v = Sin::compute(phase + (1 << 22) - (freq >> 1));
int32_t a = Sin::compute(freq >> 1);
v = ((int64_t)v * (int64_t)a) >> 17;
int32_t aa = ((int64_t)a * (int64_t)a) >> 17;
#endif
#endif
if (aa < 0) aa = (1 << 31) - 1;
for (int i = 0; i < _N_; i++) {
gain += dgain;
output[i] = ((int64_t)u * (int64_t)gain) >> 30;
v -= ((int64_t)aa * (int64_t)u) >> 29;
u += v;
}
}
#endif
#if 0
// Results:: accuracy 112.3 mean, 4262 worst (near freq = 0.5)
// high accuracy 2.9 mean, 143 worst
void FmOpKernel::compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add) {
int32_t dgain = (gain2 - gain1 + (_N_ >> 1)) >> LG_N;
int32_t gain = gain1;
int32_t phase = phase0;
#ifdef HIGH_ACCURACY
int32_t u = Sin::compute10(phase << 6);
int32_t lastu = Sin::compute10((phase - freq) << 6);
int32_t a = Sin::compute10((freq << 6) + (1 << 28)) << 1;
#else
int32_t u = Sin::compute(phase) << 6;
int32_t lastu = Sin::compute(phase - freq) << 6;
int32_t a = Sin::compute(freq + (1 << 22)) << 7;
#endif
if (a < 0 && freq < 256) a = (1 << 31) - 1;
if (a > 0 && freq > 0x7fff00) a = -(1 << 31);
for (int i = 0; i < _N_; i++) {
gain += dgain;
output[i] = ((int64_t)u * (int64_t)gain) >> 30;
//output[i] = u;
int32_t newu = (((int64_t)u * (int64_t)a) >> 30) - lastu;
lastu = u;
u = newu;
}
}
#endif

@ -0,0 +1,47 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef __FM_OP_KERNEL_H
#define __FM_OP_KERNEL_H
struct FmOpParams {
int32_t level_in; // value to be computed (from level to gain[0])
int32_t gain_out; // computed value (gain[1] to gain[0])
int32_t freq;
int32_t phase;
};
class FmOpKernel {
public:
// gain1 and gain2 represent linear step: gain for sample i is
// gain1 + (1 + i) / 64 * (gain2 - gain1)
// This is the basic FM operator. No feedback.
static void compute(int32_t *output, const int32_t *input,
int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add);
// This is a sine generator, no feedback.
static void compute_pure(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2, bool add);
// One op with feedback, no add.
static void compute_fb(int32_t *output, int32_t phase0, int32_t freq,
int32_t gain1, int32_t gain2,
int32_t *fb_buf, int fb_gain, bool add);
};
#endif

@ -0,0 +1,56 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Resolve frequency signal (1.0 in Q24 format = 1 octave) to phase delta.
// The LUT is just a global, and we'll need the init function to be called before
// use.
#include <stdint.h>
#include <math.h>
#include "freqlut.h"
#include "synth.h"
#define LG_N_SAMPLES 10
#define N_SAMPLES (1 << LG_N_SAMPLES)
#define SAMPLE_SHIFT (24 - LG_N_SAMPLES)
#define MAX_LOGFREQ_INT 20
int32_t lut[N_SAMPLES + 1];
void Freqlut::init(FRAC_NUM sample_rate) {
FRAC_NUM y = (1LL << (24 + MAX_LOGFREQ_INT)) / sample_rate;
FRAC_NUM inc = pow(2, 1.0 / N_SAMPLES);
for (int i = 0; i < N_SAMPLES + 1; i++) {
lut[i] = (int32_t)floor(y + 0.5);
y *= inc;
}
}
// Note: if logfreq is more than 20.0, the results will be inaccurate. However,
// that will be many times the Nyquist rate.
int32_t Freqlut::lookup(int32_t logfreq) {
int ix = (logfreq & 0xffffff) >> SAMPLE_SHIFT;
int32_t y0 = lut[ix];
int32_t y1 = lut[ix + 1];
int lowbits = logfreq & ((1 << SAMPLE_SHIFT) - 1);
int32_t y = y0 + ((((int64_t)(y1 - y0) * (int64_t)lowbits)) >> SAMPLE_SHIFT);
int hibits = logfreq >> 24;
return y >> (MAX_LOGFREQ_INT - hibits);
}

@ -0,0 +1,23 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include "synth.h"
class Freqlut {
public:
static void init(FRAC_NUM sample_rate);
static int32_t lookup(int32_t logfreq);
};

@ -0,0 +1,97 @@
/*
Copyright 2013 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Low frequency oscillator, compatible with DX7
#include "synth.h"
#include "sin.h"
#include "lfo.h"
uint32_t Lfo::unit_;
void Lfo::init(FRAC_NUM sample_rate) {
// constant is 1 << 32 / 15.5s / 11
Lfo::unit_ = (int32_t)(_N_ * 25190424 / sample_rate + 0.5);
}
void Lfo::reset(const uint8_t params[6]) {
int rate = params[0]; // 0..99
int sr = rate == 0 ? 1 : (165 * rate) >> 6;
sr *= sr < 160 ? 11 : (11 + ((sr - 160) >> 4));
delta_ = unit_ * sr;
int a = 99 - params[1]; // LFO delay
if (a == 99) {
delayinc_ = ~0u;
delayinc2_ = ~0u;
} else {
a = (16 + (a & 15)) << (1 + (a >> 4));
delayinc_ = unit_ * a;
a &= 0xff80;
a = max(0x80, a);
delayinc2_ = unit_ * a;
}
waveform_ = params[5];
sync_ = params[4] != 0;
}
int32_t Lfo::getsample() {
phase_ += delta_;
int32_t x;
switch (waveform_) {
case 0: // triangle
x = phase_ >> 7;
x ^= -(phase_ >> 31);
x &= (1 << 24) - 1;
return x;
case 1: // sawtooth down
return (~phase_ ^ (1U << 31)) >> 8;
case 2: // sawtooth up
return (phase_ ^ (1U << 31)) >> 8;
case 3: // square
return ((~phase_) >> 7) & (1 << 24);
case 4: // sine
return (1 << 23) + (Sin::lookup(phase_ >> 8) >> 1);
case 5: // s&h
if (phase_ < delta_) {
randstate_ = (randstate_ * 179 + 17) & 0xff;
}
x = randstate_ ^ 0x80;
return (x + 1) << 16;
}
return 1 << 23;
}
int32_t Lfo::getdelay() {
uint32_t delta = delaystate_ < (1U << 31) ? delayinc_ : delayinc2_;
uint64_t d = ((uint64_t)delaystate_) + delta;
if (d > ~0u) {
return 1 << 24;
}
delaystate_ = d;
if (d < (1U << 31)) {
return 0;
} else {
return (d >> 7) & ((1 << 24) - 1);
}
}
void Lfo::keydown() {
if (sync_) {
phase_ = (1U << 31) - 1;
}
delaystate_ = 0;
}

@ -0,0 +1,43 @@
/*
Copyright 2013 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Low frequency oscillator, compatible with DX7
class Lfo {
public:
static void init(FRAC_NUM sample_rate);
void reset(const uint8_t params[6]);
// result is 0..1 in Q24
int32_t getsample();
// result is 0..1 in Q24
int32_t getdelay();
void keydown();
private:
static uint32_t unit_;
uint32_t phase_; // Q32
uint32_t delta_;
uint8_t waveform_;
uint8_t randstate_;
bool sync_;
uint32_t delaystate_;
uint32_t delayinc_;
uint32_t delayinc2_;
};

@ -0,0 +1,93 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include "synth.h"
#include "pitchenv.h"
int PitchEnv::unit_;
void PitchEnv::init(FRAC_NUM sample_rate) {
unit_ = _N_ * (1 << 24) / (21.3 * sample_rate) + 0.5;
}
const uint8_t pitchenv_rate[] = {
1, 2, 3, 3, 4, 4, 5, 5, 6, 6, 7, 7, 8, 8, 9, 9, 10, 10, 11, 11, 12,
12, 13, 13, 14, 14, 15, 16, 16, 17, 18, 18, 19, 20, 21, 22, 23, 24,
25, 26, 27, 28, 30, 31, 33, 34, 36, 37, 38, 39, 41, 42, 44, 46, 47,
49, 51, 53, 54, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 76, 79, 82,
85, 88, 91, 94, 98, 102, 106, 110, 115, 120, 125, 130, 135, 141, 147,
153, 159, 165, 171, 178, 185, 193, 202, 211, 232, 243, 254, 255
};
const int8_t pitchenv_tab[] = {
-128, -116, -104, -95, -85, -76, -68, -61, -56, -52, -49, -46, -43,
-41, -39, -37, -35, -33, -32, -31, -30, -29, -28, -27, -26, -25, -24,
-23, -22, -21, -20, -19, -18, -17, -16, -15, -14, -13, -12, -11, -10,
-9, -8, -7, -6, -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27,
28, 29, 30, 31, 32, 33, 34, 35, 38, 40, 43, 46, 49, 53, 58, 65, 73,
82, 92, 103, 115, 127
};
void PitchEnv::set(const int r[4], const int l[4]) {
for (int i = 0; i < 4; i++) {
rates_[i] = r[i];
levels_[i] = l[i];
}
level_ = pitchenv_tab[l[3]] << 19;
down_ = true;
advance(0);
}
int32_t PitchEnv::getsample() {
if (ix_ < 3 || ((ix_ < 4) && !down_)) {
if (rising_) {
level_ += inc_;
if (level_ >= targetlevel_) {
level_ = targetlevel_;
advance(ix_ + 1);
}
} else { // !rising
level_ -= inc_;
if (level_ <= targetlevel_) {
level_ = targetlevel_;
advance(ix_ + 1);
}
}
}
return level_;
}
void PitchEnv::keydown(bool d) {
if (down_ != d) {
down_ = d;
advance(d ? 0 : 3);
}
}
void PitchEnv::advance(int newix) {
ix_ = newix;
if (ix_ < 4) {
int newlevel = levels_[ix_];
targetlevel_ = pitchenv_tab[newlevel] << 19;
rising_ = (targetlevel_ > level_);
inc_ = pitchenv_rate[rates_[ix_]] * unit_;
}
}
void PitchEnv::getPosition(char *step) {
*step = ix_;
}

@ -0,0 +1,52 @@
/*
Copyright 2013 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef __PITCHENV_H
#define __PITCHENV_H
// Computation of the DX7 pitch envelope
class PitchEnv {
public:
static void init(FRAC_NUM sample_rate);
// The rates and levels arrays are calibrated to match the Dx7 parameters
// (ie, value 0..99).
void set(const int rates[4], const int levels[4]);
// Result is in Q24/octave
int32_t getsample();
void keydown(bool down);
void getPosition(char *step);
private:
static int unit_;
int rates_[4];
int levels_[4];
int32_t level_;
int targetlevel_;
bool rising_;
int ix_;
int inc_;
bool down_;
void advance(int newix);
};
extern const uint8_t pitchenv_rate[];
extern const int8_t pitchenv_tab[];
#endif

@ -0,0 +1,35 @@
/*
Copyright 2019 Jean Pierre Cimalando.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#include <math.h>
#include "porta.h"
#include "synth.h"
void Porta::init_sr(double sampleRate)
{
// compute portamento for CC 7-bit range
for (unsigned int i = 0; i < 128; ++i) {
// number of semitones travelled
double sps = 350.0 * pow(2.0, -0.062 * i); // per second
double spf = sps / sampleRate; // per frame
double spp = spf * _N_; // per period
const int step = (1 << 24) / 12;
rates[i] = (int32_t)(0.5f + step * spp); // to pitch units
}
}
int32_t Porta::rates[128];

@ -0,0 +1,28 @@
/*
Copyright 2019 Jean Pierre Cimalando.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef SYNTH_PORTA_H_
#define SYNTH_PORTA_H_
#include <stdint.h>
struct Porta {
public:
static void init_sr(double sampleRate);
static int32_t rates[128];
};
#endif

@ -0,0 +1,144 @@
/*
* Copyright 2012 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#define _USE_MATH_DEFINES
#include <math.h>
#include "synth.h"
#include "sin.h"
#define R (1 << 29)
#ifdef SIN_DELTA
int32_t sintab[SIN_N_SAMPLES << 1];
#else
int32_t sintab[SIN_N_SAMPLES + 1];
#endif
void Sin::init() {
FRAC_NUM dphase = 2 * M_PI / SIN_N_SAMPLES;
//int32_t c = (int32_t)floor(cos(dphase) * (1 << 30) + 0.5);
int32_t c = (int32_t)floor(COS_FUNC(dphase) * (1 << 30) + 0.5);
//int32_t s = (int32_t)floor(sin(dphase) * (1 << 30) + 0.5);
int32_t s = (int32_t)floor(SIN_FUNC(dphase) * (1 << 30) + 0.5);
int32_t u = 1 << 30;
int32_t v = 0;
for (int i = 0; i < SIN_N_SAMPLES / 2; i++) {
#ifdef SIN_DELTA
sintab[(i << 1) + 1] = (v + 32) >> 6;
sintab[((i + SIN_N_SAMPLES / 2) << 1) + 1] = -((v + 32) >> 6);
#else
sintab[i] = (v + 32) >> 6;
sintab[i + SIN_N_SAMPLES / 2] = -((v + 32) >> 6);
#endif
int32_t t = ((int64_t)u * (int64_t)s + (int64_t)v * (int64_t)c + R) >> 30;
u = ((int64_t)u * (int64_t)c - (int64_t)v * (int64_t)s + R) >> 30;
v = t;
}
#ifdef SIN_DELTA
for (int i = 0; i < SIN_N_SAMPLES - 1; i++) {
sintab[i << 1] = sintab[(i << 1) + 3] - sintab[(i << 1) + 1];
}
sintab[(SIN_N_SAMPLES << 1) - 2] = -sintab[(SIN_N_SAMPLES << 1) - 1];
#else
sintab[SIN_N_SAMPLES] = 0;
#endif
}
#ifndef SIN_INLINE
int32_t Sin::lookup(int32_t phase) {
const int SHIFT = 24 - SIN_LG_N_SAMPLES;
int lowbits = phase & ((1 << SHIFT) - 1);
#ifdef SIN_DELTA
int phase_int = (phase >> (SHIFT - 1)) & ((SIN_N_SAMPLES - 1) << 1);
int dy = sintab[phase_int];
int y0 = sintab[phase_int + 1];
return y0 + (((int64_t)dy * (int64_t)lowbits) >> SHIFT);
#else
int phase_int = (phase >> SHIFT) & (SIN_N_SAMPLES - 1);
int y0 = sintab[phase_int];
int y1 = sintab[phase_int + 1];
return y0 + (((int64_t)(y1 - y0) * (int64_t)lowbits) >> SHIFT);
#endif
}
#endif
#if 0
// The following is an implementation designed not to use any lookup tables,
// based on the following implementation by Basile Graf:
// http://www.rossbencina.com/static/code/sinusoids/even_polynomial_sin_approximation.txt
#define C0 (1 << 24)
#define C1 (331121857 >> 2)
#define C2 (1084885537 >> 4)
#define C3 (1310449902 >> 6)
int32_t Sin::compute(int32_t phase) {
int32_t x = (phase & ((1 << 23) - 1)) - (1 << 22);
int32_t x2 = ((int64_t)x * (int64_t)x) >> 22;
int32_t x4 = ((int64_t)x2 * (int64_t)x2) >> 24;
int32_t x6 = ((int64_t)x2 * (int64_t)x4) >> 24;
int32_t y = C0 -
(((int64_t)C1 * (int64_t)x2) >> 24) +
(((int64_t)C2 * (int64_t)x4) >> 24) -
(((int64_t)C3 * (int64_t)x6) >> 24);
y ^= -((phase >> 23) & 1);
return y;
}
#endif
#if 1
// coefficients are Chebyshev polynomial, computed by compute_cos_poly.py
#define C8_0 16777216
#define C8_2 -331168742
#define C8_4 1089453524
#define C8_6 -1430910663
#define C8_8 950108533
int32_t Sin::compute(int32_t phase) {
int32_t x = (phase & ((1 << 23) - 1)) - (1 << 22);
int32_t x2 = ((int64_t)x * (int64_t)x) >> 16;
int32_t y = (((((((((((((int64_t)C8_8
* (int64_t)x2) >> 32) + C8_6)
* (int64_t)x2) >> 32) + C8_4)
* (int64_t)x2) >> 32) + C8_2)
* (int64_t)x2) >> 32) + C8_0);
y ^= -((phase >> 23) & 1);
return y;
}
#endif
#define C10_0 (1 << 30)
#define C10_2 -1324675874 // scaled * 4
#define C10_4 1089501821
#define C10_6 -1433689867
#define C10_8 1009356886
#define C10_10 -421101352
int32_t Sin::compute10(int32_t phase) {
int32_t x = (phase & ((1 << 29) - 1)) - (1 << 28);
int32_t x2 = ((int64_t)x * (int64_t)x) >> 26;
int32_t y = ((((((((((((((((int64_t)C10_10
* (int64_t)x2) >> 34) + C10_8)
* (int64_t)x2) >> 34) + C10_6)
* (int64_t)x2) >> 34) + C10_4)
* (int64_t)x2) >> 32) + C10_2)
* (int64_t)x2) >> 30) + C10_0);
y ^= -((phase >> 29) & 1);
return y;
}

@ -0,0 +1,62 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
class Sin {
public:
Sin();
static void init();
static int32_t lookup(int32_t phase);
static int32_t compute(int32_t phase);
// A more accurate sine, both input and output Q30
static int32_t compute10(int32_t phase);
};
#define SIN_LG_N_SAMPLES 10
#define SIN_N_SAMPLES (1 << SIN_LG_N_SAMPLES)
#define SIN_INLINE
// Use twice as much RAM for the LUT but avoid a little computation
#define SIN_DELTA
#ifdef SIN_DELTA
extern int32_t sintab[SIN_N_SAMPLES << 1];
#else
extern int32_t sintab[SIN_N_SAMPLES + 1];
#endif
#ifdef SIN_INLINE
inline
int32_t Sin::lookup(int32_t phase) {
const int SHIFT = 24 - SIN_LG_N_SAMPLES;
int lowbits = phase & ((1 << SHIFT) - 1);
#ifdef SIN_DELTA
int phase_int = (phase >> (SHIFT - 1)) & ((SIN_N_SAMPLES - 1) << 1);
int dy = sintab[phase_int];
int y0 = sintab[phase_int + 1];
return y0 + (((int64_t)dy * (int64_t)lowbits) >> SHIFT);
#else
int phase_int = (phase >> SHIFT) & (SIN_N_SAMPLES - 1);
int y0 = sintab[phase_int];
int y1 = sintab[phase_int + 1];
return y0 + (((int64_t)(y1 - y0) * (int64_t)lowbits) >> SHIFT);
#endif
}
#endif

@ -0,0 +1,81 @@
/*
Copyright 2012 Google Inc.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
#ifndef SYNTH_H
#define SYNTH_H
//#define SUPER_PRECISE
#include <Arduino.h>
#define MIDI_CONTROLLER_MODE_MAX 2
#define TRANSPOSE_FIX 24
#define VOICE_SILENCE_LEVEL 1100
#define _MAX_NOTES 32
// This IS not be present on MSVC.
// See http://stackoverflow.com/questions/126279/c99-stdint-h-header-and-ms-visual-studio
#ifdef _MSC_VER
typedef __int32 int32_t;
typedef unsigned __int32 uint32_t;
typedef __int16 SInt16;
#endif
#define LG_N 6
#define _N_ (1 << LG_N)
#if defined(__APPLE__)
#include <libkern/OSAtomic.h>
#define SynthMemoryBarrier() OSMemoryBarrier()
#elif defined(__GNUC__)
#if (__GNUC__ > 4) || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1)
#define SynthMemoryBarrier() __sync_synchronize()
#endif
#endif
// #undef SynthMemoryBarrier()
#ifndef SynthMemoryBarrier
// need to understand why this must be defined
// #warning Memory barrier is not enabled
#define SynthMemoryBarrier()
#endif
template<typename T>
inline static T min(const T& a, const T& b) {
return a < b ? a : b;
}
template<typename T>
inline static T max(const T& a, const T& b) {
return a > b ? a : b;
}
#define QER(n,b) ( ((float)n)/(1<<b) )
#define FRAC_NUM float
#define SIN_FUNC sinf
// #define SIN_FUNC arm_sin_f32 // very fast but not as accurate
#define COS_FUNC cosf
// #define COS_FUNC arm_cos_f32 // very fast but not as accurate
#define LOG_FUNC logf
#define EXP_FUNC expf
#define SQRT_FUNC sqrtf
// #define ARM_SQRT_FUNC arm_sqrt_f32 // fast but not as accurate
#endif

File diff suppressed because it is too large Load Diff

File diff suppressed because it is too large Load Diff

@ -1,50 +0,0 @@
/*
MicroDexed
MicroDexed is a port of the Dexed sound engine
(https://github.com/asb2m10/dexed) for the Teensy-3.5/3.6/4.x with audio shield.
Dexed ist heavily based on https://github.com/google/music-synthesizer-for-android
(c)2018-2021 H. Wirtz <wirtz@parasitstudio.de>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef TEENSY_BOARD_DETECTION_H_INCLUDED
#define TEENSY_BOARD_DETECTION_H_INCLUDED
// Teensy-4.x
#if defined(__IMXRT1062__) || defined (ARDUINO_TEENSY40) || defined (ARDUINO_TEENSY41)
#define TEENSY4
#if defined (ARDUINO_TEENSY40)
#define TEENSY4_0
#elif defined (ARDUINO_TEENSY41)
#define TEENSY4_1
#endif
#endif
// Teensy-3.6
#if defined(__MK66FX1M0__)
# define TEENSY3_6
#endif
// Teensy-3.5
#if defined (__MK64FX512__)
#define TEENSY3_5
#endif
#endif
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