Improved Oscillators -- fixed

data/projects/templates/default.mpt

@@ -7,7 +7,7 @@
       <track muted="0" type="0" name="TripleOscillator" solo="0">
         <instrumenttrack pan="0" fxch="0" usemasterpitch="1" pitchrange="1" pitch="0" basenote="57" vol="100">
           <instrument name="tripleoscillator">
-            <tripleoscillator phoffset2="0" userwavefile0="" finer0="0" userwavefile1="" finer1="0" userwavefile2="" finer2="0" coarse0="0" coarse1="-12" coarse2="-24" finel0="0" finel1="0" modalgo1="2" modalgo2="2" finel2="0" pan0="0" modalgo3="2" pan1="0" stphdetun0="0" pan2="0" stphdetun1="0" wavetype0="0" stphdetun2="0" wavetype1="0" wavetype2="0" vol0="33" vol1="33" phoffset0="0" phoffset1="0" vol2="33"/>
+            <tripleoscillator phoffset2="0" userwavefile0="" finer0="0" userwavefile1="" finer1="0" userwavefile2="" finer2="0" coarse0="0" coarse1="-12" coarse2="-24" finel0="0" finel1="0" modalgo1="2" modalgo2="2" finel2="0" pan0="0" modalgo3="2" pan1="0" stphdetun0="0" pan2="0" stphdetun1="0" wavetype0="0" stphdetun2="0" wavetype1="0" wavetype2="0" vol0="33" vol1="33" phoffset0="0" phoffset1="0" vol2="33" useWaveTable1="1" useWaveTable2="1" useWaveTable3="1"/>
           </instrument>
           <eldata fres="0.5" ftype="0" fcut="14000" fwet="0">
             <elvol lspd_denominator="4" sustain="0.5" pdel="0" userwavefile="" dec="0.5" lamt="0" latt="0" rel="0.1" amt="0" x100="0" att="0" lpdel="0" hold="0.5" lspd_syncmode="0" lshp="0" lspd="0.1" ctlenvamt="0" lspd_numerator="4"/>

include/DataFile.h

@@ -121,6 +121,7 @@ class LMMS_EXPORT DataFile : public QDomDocument
 	void upgrade_noHiddenClipNames();
 	void upgrade_automationNodes();
 	void upgrade_extendedNoteRange();
+	void upgrade_defaultTripleOscillatorHQ();
 
 	// List of all upgrade methods
 	static const std::vector<UpgradeMethod> UPGRADE_METHODS;

include/Oscillator.h

@@ -2,6 +2,7 @@
  * Oscillator.h - declaration of class Oscillator
  *
  * Copyright (c) 2004-2014 Tobias Doerffel <tobydox/at/users.sourceforge.net>
+ *               2018      Dave French	<dave/dot/french3/at/googlemail/dot/com>
  *
  * This file is part of LMMS - https://lmms.io
  *
@@ -25,16 +26,20 @@
 #ifndef OSCILLATOR_H
 #define OSCILLATOR_H
 
-#include "lmmsconfig.h"
-
+#include <cassert>
+#include <fftw3.h>
 #include <math.h>
 
 #ifdef LMMS_HAVE_STDLIB_H
 #include <stdlib.h>
 #endif
 
-#include "SampleBuffer.h"
+#include "Engine.h"
 #include "lmms_constants.h"
+#include "lmmsconfig.h"
+#include "Mixer.h"
+#include "OscillatorConstants.h"
+#include "SampleBuffer.h"
 
 class IntModel;
 
@@ -53,8 +58,10 @@ class LMMS_EXPORT Oscillator
 		ExponentialWave,
 		WhiteNoise,
 		UserDefinedWave,
-		NumWaveShapes
-	} ;
+		NumWaveShapes,                                         //!< Number of all available wave shapes
+		FirstWaveShapeTable = TriangleWave,                    //!< First wave shape that has a pre-generated table
+		NumWaveShapeTables = WhiteNoise - FirstWaveShapeTable, //!< Number of band-limited wave shapes to be generated
+	};
 
 	enum ModulationAlgos
 	{
@@ -67,29 +74,35 @@ class LMMS_EXPORT Oscillator
 	} ;
 
 
-	Oscillator( const IntModel * _wave_shape_model,
-			const IntModel * _mod_algo_model,
-			const float & _freq,
-			const float & _detuning,
-			const float & _phase_offset,
-			const float & _volume,
-			Oscillator * _m_subOsc = NULL );
+	Oscillator( const IntModel *wave_shape_model,
+			const IntModel *mod_algo_model,
+			const float &freq,
+			const float &detuning_div_samplerate,
+			const float &phase_offset,
+			const float &volume,
+			Oscillator *m_subOsc = nullptr);
 	virtual ~Oscillator()
 	{
 		delete m_subOsc;
 	}
 
+	static void waveTableInit();
+	static void destroyFFTPlans();
+	static void generateAntiAliasUserWaveTable(SampleBuffer* sampleBuffer);
+
+	inline void setUseWaveTable(bool n)
+	{
+		m_useWaveTable = n;
+	}
 
 	inline void setUserWave( const SampleBuffer * _wave )
 	{
 		m_userWave = _wave;
 	}
 
-	void update( sampleFrame * _ab, const fpp_t _frames,
-							const ch_cnt_t _chnl );
+	void update(sampleFrame* ab, const fpp_t frames, const ch_cnt_t chnl, bool modulator = false);
 
 	// now follow the wave-shape-routines...
-
 	static inline sample_t sinSample( const float _sample )
 	{
 		return sinf( _sample * F_2PI );
@@ -153,18 +166,104 @@ class LMMS_EXPORT Oscillator
 		return m_userWave->userWaveSample( _sample );
 	}
 
+	struct wtSampleControl {
+		float frame;
+		f_cnt_t f1;
+		f_cnt_t f2;
+		int band;
+	};
+
+	inline wtSampleControl getWtSampleControl(const float sample) const
+	{
+		wtSampleControl control;
+		control.frame = sample * OscillatorConstants::WAVETABLE_LENGTH;
+		control.f1 = static_cast<f_cnt_t>(control.frame) % OscillatorConstants::WAVETABLE_LENGTH;
+		if (control.f1 < 0)
+		{
+			control.f1 += OscillatorConstants::WAVETABLE_LENGTH;
+		}
+		control.f2 = control.f1 < OscillatorConstants::WAVETABLE_LENGTH - 1 ?
+					control.f1 + 1 :
+					0;
+		control.band = waveTableBandFromFreq(m_freq * m_detuning_div_samplerate * Engine::mixer()->processingSampleRate());
+		return control;
+	}
+
+	inline sample_t wtSample(
+		const sample_t table[OscillatorConstants::WAVE_TABLES_PER_WAVEFORM_COUNT][OscillatorConstants::WAVETABLE_LENGTH],
+		const float sample) const
+	{
+		assert(table != nullptr);
+		wtSampleControl control = getWtSampleControl(sample);
+		return linearInterpolate(table[control.band][control.f1],
+				table[control.band][control.f2], fraction(control.frame));
+	}
+
+	inline sample_t wtSample(const std::unique_ptr<OscillatorConstants::waveform_t>& table, const float sample) const
+	{
+		assert(table != nullptr);
+		wtSampleControl control = getWtSampleControl(sample);
+		return linearInterpolate((*table)[control.band][control.f1],
+				(*table)[control.band][control.f2], fraction(control.frame));
+	}
+
+	inline sample_t wtSample(sample_t **table, const float sample) const
+	{
+		assert(table != nullptr);
+		wtSampleControl control = getWtSampleControl(sample);
+		return linearInterpolate(table[control.band][control.f1],
+				table[control.band][control.f2], fraction(control.frame));
+	}
+
+	static inline int waveTableBandFromFreq(float freq)
+	{
+		// Frequency bands are indexed relative to default MIDI key frequencies.
+		// I.e., 440 Hz (A4, key 69): 69 + 12 * log2(1) = 69
+		// To always avoid aliasing, ceil() is used instead of round(). It ensures that the nearest wavetable with
+		// lower than optimal number of harmonics is used when exactly matching wavetable is not available.
+		int band = (69 + static_cast<int>(std::ceil(12.0f * std::log2(freq / 440.0f)))) / OscillatorConstants::SEMITONES_PER_TABLE;
+		// Limit the returned value to a valid wavetable index range.
+		// (qBound would bring Qt into the audio code, which not a preferable option due to realtime safety.
+		// C++17 std::clamp() could be used in the future.)
+		return band <= 1 ? 1 : band >= OscillatorConstants::WAVE_TABLES_PER_WAVEFORM_COUNT-1 ? OscillatorConstants::WAVE_TABLES_PER_WAVEFORM_COUNT-1 : band;
+	}
+
+	static inline float freqFromWaveTableBand(int band)
+	{
+		return 440.0f * std::pow(2.0f, (band * OscillatorConstants::SEMITONES_PER_TABLE - 69.0f) / 12.0f);
+	}
 
 private:
 	const IntModel * m_waveShapeModel;
 	const IntModel * m_modulationAlgoModel;
 	const float & m_freq;
-	const float & m_detuning;
+	const float & m_detuning_div_samplerate;
 	const float & m_volume;
 	const float & m_ext_phaseOffset;
 	Oscillator * m_subOsc;
 	float m_phaseOffset;
 	float m_phase;
 	const SampleBuffer * m_userWave;
+	bool m_useWaveTable;
+	// There are many update*() variants; the modulator flag is stored as a member variable to avoid
+	// adding more explicit parameters to all of them. Can be converted to a parameter if needed.
+	bool m_isModulator;
+
+	/* Multiband WaveTable */
+	static sample_t s_waveTables[WaveShapes::NumWaveShapeTables][OscillatorConstants::WAVE_TABLES_PER_WAVEFORM_COUNT][OscillatorConstants::WAVETABLE_LENGTH];
+	static fftwf_plan s_fftPlan;
+	static fftwf_plan s_ifftPlan;
+	static fftwf_complex * s_specBuf;
+	static float s_sampleBuffer[OscillatorConstants::WAVETABLE_LENGTH];
+
+	static void generateSawWaveTable(int bands, sample_t* table, int firstBand = 1);
+	static void generateTriangleWaveTable(int bands, sample_t* table, int firstBand = 1);
+	static void generateSquareWaveTable(int bands, sample_t* table, int firstBand = 1);
+	static void generateFromFFT(int bands, sample_t* table);
+	static void generateWaveTables();
+	static void createFFTPlans();
+
+	/* End Multiband wavetable */
 
 
 	void updateNoSub( sampleFrame * _ab, const fpp_t _frames,

include/OscillatorConstants.h

@@ -0,0 +1,57 @@
+/*
+ * OscillatorConstants.h - declaration of constants used in  Oscillator and SampleBuffer
+ * for band limited wave tables
+ *
+ * Copyright (c) 2018      Dave French	<dave/dot/french3/at/googlemail/dot/com>
+ *
+ * This file is part of LMMS - https://lmms.io
+ *
+ * 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 2 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 (see COPYING); if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301 USA.
+ *
+ */
+
+#ifndef OSCILLATORCONSTANTS_H
+#define OSCILLATORCONSTANTS_H
+
+#include <array>
+
+#include "lmms_basics.h"
+
+namespace OscillatorConstants
+{
+	// Limit wavetables to the audible audio spectrum
+	const int MAX_FREQ = 20000;
+	// Minimum size of table to have all audible bands for midi note 1 (i.e. 20 000 Hz / 8.176 Hz)
+	constexpr int WAVETABLE_LENGTH = static_cast<int>(MAX_FREQ / 8.176);
+
+	//SEMITONES_PER_TABLE, the smaller the value the smoother the harmonics change on frequency sweeps
+	// with the trade off of increased memory requirements to store the wave tables
+	// require memory = NumberOfWaveShapes*WAVETABLE_LENGTH*(MidiNoteCount/SEMITONES_PER_TABLE)*BytePerSample_t
+	// 7*2446*(128/1)*4 = 8766464 bytes
+	const int SEMITONES_PER_TABLE = 1;
+	const int WAVE_TABLES_PER_WAVEFORM_COUNT = 128 / SEMITONES_PER_TABLE;
+
+	// There is some ambiguity around the use of "wavetable", "wavetable synthesis" or related terms.
+	// The following meanings and definitions were selected for use in the Oscillator class:
+	//  - wave shape: abstract and precise definition of the graph associated with a given type of wave;
+	//  - waveform: digital representations the wave shape, a set of waves optimized for use at varying pitches;
+	//  - wavetable: a table containing one period of a wave, with frequency content optimized for a specific pitch.
+	typedef std::array<sample_t, WAVETABLE_LENGTH> wavetable_t;
+	typedef std::array<wavetable_t,	WAVE_TABLES_PER_WAVEFORM_COUNT> waveform_t;
+};
+
+
+#endif // OSCILLATORCONSTANTS_H

include/SampleBuffer.h

@@ -26,6 +26,7 @@
 #ifndef SAMPLE_BUFFER_H
 #define SAMPLE_BUFFER_H
 
+#include <memory>
 #include <QtCore/QReadWriteLock>
 #include <QtCore/QObject>
 
@@ -36,6 +37,7 @@
 #include "lmms_basics.h"
 #include "lmms_math.h"
 #include "shared_object.h"
+#include "OscillatorConstants.h"
 #include "MemoryManager.h"
 
 
@@ -273,6 +275,9 @@ class LMMS_EXPORT SampleBuffer : public QObject, public sharedObject
 	}
 
 
+	std::unique_ptr<OscillatorConstants::waveform_t> m_userAntiAliasWaveTable;
+
+
 public slots:
 	void setAudioFile(const QString & audioFile);
 	void loadFromBase64(const QString & data);