C++-ified everything

CMakeLists.txt

@@ -4,6 +4,7 @@ project(SELCALToneGenerator VERSION 0.1.0)
 set(CMAKE_CXX_STANDARD 17)
 
 add_subdirectory(fluidsynth)
+add_subdirectory(magic_enum)
 
 file(GLOB_RECURSE sources src/*.cpp src/*.h)
 file(GLOB_RECURSE data resources/*)
@@ -11,3 +12,4 @@ file(GLOB_RECURSE data resources/*)
 add_executable(tone-generator ${sources} ${data})
 
 target_link_libraries(tone-generator PRIVATE libfluidsynth)
+target_link_libraries(tone-generator PRIVATE magic_enum::magic_enum)

README.md

@@ -7,6 +7,7 @@ Assumes that the fluidsynth sources are in the fluidsynth/ directory.
 
 ```
 git clone https://github.com/FluidSynth/fluidsynth.git
+git clone https://github.com/Neargye/magic_enum.git
 mkdir build
 cd build
 cmake ..

src/code.cpp

@@ -0,0 +1,14 @@
+#include "code.h"
+
+namespace SELCAL {
+
+Code::Code(std::string s) : code(s) {
+
+}
+
+bool Code::isValid() const {
+    // TODO JMT
+    return false;
+}
+
+} // SELCAL

src/code.h

@@ -0,0 +1,61 @@
+#pragma once
+
+#include <string>
+#include <array>
+#include <vector>
+
+
+namespace SELCAL {
+
+constexpr int KEYS_PER_GROUP = 2;
+constexpr char GROUP_SEPARATOR = '-';
+
+enum class Key : char {
+    KEY_1 = '1',
+    KEY_2 = '2',
+    KEY_3 = '3',
+    KEY_4 = '4',
+    KEY_5 = '5',
+    KEY_6 = '6',
+    KEY_7 = '7',
+    KEY_8 = '8',
+    KEY_9 = '9',
+    KEY_A = 'A',
+    KEY_B = 'B',
+    KEY_C = 'C',
+    KEY_D = 'D',
+    KEY_E = 'E',
+    KEY_F = 'F',
+    KEY_G = 'G',
+    KEY_H = 'H',
+    KEY_J = 'J',
+    KEY_K = 'K',
+    KEY_L = 'L',
+    KEY_M = 'M',
+    KEY_P = 'P',
+    KEY_Q = 'Q',
+    KEY_R = 'R',
+    KEY_S = 'S',
+    KEY_T = 'T',
+    KEY_U = 'U',
+    KEY_V = 'V',
+    KEY_W = 'W',
+    KEY_X = 'X',
+    KEY_Y = 'Y',
+    KEY_Z = 'Z',
+};
+
+typedef std::array<Key, KEYS_PER_GROUP> Group;
+
+class Code {
+public:
+    Code(std::string s);
+
+private:
+    bool isValid() const;
+
+    const std::string code;
+    const std::vector<Group> groups;
+};
+
+} // SELCAL

src/main.cpp

@@ -1,126 +1,107 @@
-/*
-
-  An example of how to use FluidSynth.
-
-  To compile it on Linux:
-  $ gcc -o example example.c `pkg-config fluidsynth --libs`
-
-  To compile it on Windows:
-    ...
-
-
-  Author: Peter Hanappe.
-  This code is in the public domain. Use it as you like.
-
-*/
-
-#include <fluidsynth.h>
+#include "synth.h"
+#include "code.h"
 #include <iostream>
+#include <map>
+#include <magic_enum.hpp>
+#include "midi.h"
 
-#if defined(_WIN32)
-#include <windows.h>
-#define sleep(_t) Sleep(_t * 1000)
-#include <process.h>
-#define getpid _getpid
-#else
-#include <stdlib.h>
-#include <unistd.h>
-#endif
+#include <thread>
+#include <chrono>
+
+int main(int argc, char** argv) {
+
+    Synth synth;
+
+    for(int i = 1; i < argc; ++i) {
+        synth.loadSoundfont(argv[i]);
+    }
+
+    for (const Synth::Program& program : synth.getPrograms()) {
+        std::cout << program.name << " " << program.soundfontId
+            << ":(" << program.bankNumber << ", " << program.programNumber << ")"
+            << std::endl;
+
+        if (program.name == "Tuba") {
+            std::cout << "Loading program!" << std::endl;
+            synth.loadProgram(program);
+        }
+    }
+
+    std::map<SELCAL::Key, double> keyFrequencies = {
+        {SELCAL::Key::KEY_1, 680.0},
+        {SELCAL::Key::KEY_2, 754.2},
+        {SELCAL::Key::KEY_3, 836.6},
+        {SELCAL::Key::KEY_4, 927.9},
+        {SELCAL::Key::KEY_5, 1029.2},
+        {SELCAL::Key::KEY_6, 1141.6},
+        {SELCAL::Key::KEY_7, 1266.2},
+        {SELCAL::Key::KEY_8, 1404.4},
+        {SELCAL::Key::KEY_9, 1557.8},
+        {SELCAL::Key::KEY_A, 312.6},
+        {SELCAL::Key::KEY_B, 346.7},
+        {SELCAL::Key::KEY_C, 384.6},
+        {SELCAL::Key::KEY_D, 426.6},
+        {SELCAL::Key::KEY_E, 473.2},
+        {SELCAL::Key::KEY_F, 524.8},
+        {SELCAL::Key::KEY_G, 582.1},
+        {SELCAL::Key::KEY_H, 645.7},
+        {SELCAL::Key::KEY_J, 716.1},
+        {SELCAL::Key::KEY_K, 794.3},
+        {SELCAL::Key::KEY_L, 881.0},
+        {SELCAL::Key::KEY_M, 977.2},
+        {SELCAL::Key::KEY_P, 1083.9},
+        {SELCAL::Key::KEY_Q, 1202.3},
+        {SELCAL::Key::KEY_R, 1333.5},
+        {SELCAL::Key::KEY_S, 1479.1},
+        {SELCAL::Key::KEY_T, 329.2},
+        {SELCAL::Key::KEY_U, 365.2},
+        {SELCAL::Key::KEY_V, 405.0},
+        {SELCAL::Key::KEY_W, 449.3},
+        {SELCAL::Key::KEY_X, 498.3},
+        {SELCAL::Key::KEY_Y, 552.7},
+        {SELCAL::Key::KEY_Z, 613.1},
+    };
+
+    std::array<double, NUM_MIDI_NOTES> tunings;
+    tunings.fill(0);
+
+
+    for (auto pair : keyFrequencies) {
+        std::cout
+            << magic_enum::enum_name(pair.first) << " = "
+            << pair.second << " Hz "
+            << " or MIDI key " << frequencyToMidi(pair.second)
+            << std::endl;
+
+        // fluidsynth wants tunings in MIDI cents, which effectively means MIDI key * 100.
+        // As we only care about the SELCAL 32 tones, only tune those specific keys. We don't
+        // need to tune the full 128-key keyboard.
+        constexpr double MIDI_CENT_SCALE = 100.0;
+        const int keyIndex = static_cast<int>(pair.first);
+        tunings[keyIndex] = frequencyToMidi(pair.second * MIDI_CENT_SCALE);
+    }
+
+    bool success = synth.setTuning(tunings);
+    std::cout << "Set tuning: " << (success ? "success" : "failed") << std::endl;
+
+
+    fluid_synth_t* raw_synth = synth.getSynth();
+    using namespace std::chrono_literals;
 
-int main(int argc, char **argv)
-{
-    fluid_settings_t *settings = NULL;
-    fluid_synth_t *synth = NULL;
-    fluid_audio_driver_t *adriver = NULL;
-    int sfont_id;
     int i, key;
-
-    fluid_sfont_t* sfont = nullptr;
-    fluid_preset_t* preset = nullptr;
-
-    /* Create the settings. */
-    settings = new_fluid_settings();
-    if(settings == NULL)
-    {
-        puts("Failed to create the settings!");
-        goto err;
-    }
-
-    /* Change the settings if necessary*/
-
-    /* Create the synthesizer. */
-    synth = new_fluid_synth(settings);
-    if(synth == NULL)
-    {
-        puts("Failed to create the synth!");
-        goto err;
-    }
-
-    /* Load a SoundFont and reset presets (so that new instruments
-     * get used from the SoundFont)
-     * Depending on the size of the SoundFont, this will take some time to complete...
-     */
-    sfont_id = fluid_synth_sfload(synth, argv[1], 1);
-    if(sfont_id == FLUID_FAILED)
-    {
-        puts("Loading the SoundFont failed!");
-        goto err;
-    }
-
-    // Get the SoundFont
-    sfont = fluid_synth_get_sfont_by_id(synth, sfont_id);
-
-    if (!sfont) {
-        std::cerr << "Failed to get SoundFont by ID" << std::endl;
-        delete_fluid_synth(synth);
-        delete_fluid_settings(settings);
-        return 1;
-    }
-
-    // Enumerate the presets (programs) in the SoundFont
-
-    std::cout << "Programs in SoundFont " << argv[1] << ":" << std::endl;
-    fluid_sfont_iteration_start(sfont);
-    while ((preset = fluid_sfont_iteration_next(sfont)) != nullptr) {
-        std::cout << "Bank: " << fluid_preset_get_banknum(preset)
-                  << ", Program: " << fluid_preset_get_num(preset)
-                  << ", Name: " << fluid_preset_get_name(preset) << std::endl;
-    }
-
-    fluid_synth_program_select(synth, 0, sfont_id, 0, 0);
-
-    /* Create the audio driver. The synthesizer starts playing as soon
-       as the driver is created. */
-    adriver = new_fluid_audio_driver(settings, synth);
-    if(adriver == NULL)
-    {
-        puts("Failed to create the audio driver!");
-        goto err;
-    }
-
-    /* Initialize the random number generator */
-    srand(getpid());
-
     for(i = 0; i < 12; i++)
     {
         /* Generate a random key */
-        key = 60 + (int)(12.0f * rand() / (float) RAND_MAX);
+        key = 30 + (int)(12.0f * rand() / (float) RAND_MAX);
 
         /* Play a note */
-        fluid_synth_noteon(synth, 0, key, 100);
+        fluid_synth_noteon(raw_synth, 0, key, 100);
 
         /* Sleep for 1 second */
-        sleep(1);
+        std::this_thread::sleep_for(1s);
 
         /* Stop the note */
-        fluid_synth_noteoff(synth, 0, key);
+        fluid_synth_noteoff(raw_synth, 0, key);
     }
 
-err:
-    /* Clean up */
-    delete_fluid_audio_driver(adriver);
-    delete_fluid_synth(synth);
-    delete_fluid_settings(settings);
-
-    return 0;
 }

src/midi.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include <cmath>
+
+double frequencyToMidi(double f) {
+    return ((12 * std::log(f / 220.0) / std::log(2.0)) + 57.01);
+}
+
+int frequencyToNearestMidi(double f) {
+    return (int) frequencyToMidi(f);
+}

src/synth.cpp

@@ -0,0 +1,101 @@
+#include "synth.h"
+
+#include <stdexcept>
+
+Synth::Synth() {
+    try {
+        settings = new_fluid_settings();
+        if (settings == nullptr) {
+            throw new std::runtime_error("Unable to create fluid settings");
+        }
+
+        synth = new_fluid_synth(settings);
+        if (synth == nullptr) {
+            throw new std::runtime_error("Unable to create fluid synth");
+        }
+
+        adriver = new_fluid_audio_driver(settings, synth);
+        if (adriver == nullptr) {
+            throw new std::runtime_error("Unable to create audio driver");
+        }
+    }
+    catch (std::runtime_error& e) {
+        // Do a mem-safe cleanup and rethrow.
+        // TODO JMT: Do these handle receiving nullptr for deletes?
+        delete_fluid_audio_driver(adriver);
+        delete_fluid_synth(synth);
+        delete_fluid_settings(settings);
+        throw;
+    }
+}
+
+Synth::~Synth() {
+    // TODO JMT: Do I need to manually clear all of the soundfonts and programs I have handles for?
+    delete_fluid_audio_driver(adriver);
+    delete_fluid_synth(synth);
+    delete_fluid_settings(settings);
+}
+
+bool Synth::loadSoundfont(const std::string& filepath) {
+    int soundfontId = fluid_synth_sfload(synth, filepath.c_str(), 1);
+    if(soundfontId == FLUID_FAILED) {
+        return false;
+    }
+
+    fluid_sfont_t* soundfontHandle = fluid_synth_get_sfont_by_id(synth, soundfontId);
+    const std::string soundfontName{fluid_sfont_get_name(soundfontHandle)};
+
+    Synth::Soundfont soundfont{soundfontName, soundfontId};
+    soundfonts.push_back(soundfont);
+
+    fluid_preset_t* preset = nullptr;
+    fluid_sfont_iteration_start(soundfontHandle);
+    while ((preset = fluid_sfont_iteration_next(soundfontHandle)) != nullptr) {
+        const std::string presetName{fluid_preset_get_name(preset)};
+        const int bankNumber = fluid_preset_get_banknum(preset);
+        const int programNumber = fluid_preset_get_num(preset);
+
+        Synth::Program program {presetName, soundfontId, bankNumber, programNumber};
+        programs.push_back(program);
+    }
+
+    return true;
+}
+
+bool Synth::loadProgram(const Program& program) {
+    // TODO JMT: fix this
+    fluid_synth_program_select(synth, 0, program.soundfontId, program.bankNumber, program.programNumber);
+    return true;
+}
+
+bool Synth::setTuning(const std::array<double, NUM_MIDI_NOTES>& pitches) {
+    int result = fluid_synth_activate_key_tuning(
+        synth,
+        0, 0,
+        "default",
+        pitches.data(),
+        1
+    );
+
+    return result == FLUID_OK;
+}
+
+bool Synth::resetTuning() {
+    int result = fluid_synth_activate_key_tuning(
+        synth,
+        0, 0,
+        "default",
+        nullptr,
+        1
+    );
+
+    return result == FLUID_OK;
+}
+
+const std::vector<Synth::Program>& Synth::getPrograms() const {
+    return programs;
+}
+
+fluid_synth_t* Synth::getSynth() {
+    return synth;
+}

src/synth.h

@@ -0,0 +1,50 @@
+#pragma once
+
+#include <fluidsynth.h>
+#include <vector>
+#include <string>
+#include <array>
+
+constexpr int NUM_MIDI_NOTES = 128;
+
+/**
+ * C++ wrapper around the fluidsynth API.
+ */
+class Synth {
+public:
+    Synth();
+    ~Synth();
+
+    struct Soundfont {
+        std::string name;
+        int id;
+    };
+
+    struct Program {
+        std::string name;
+        int soundfontId;
+        int bankNumber;
+        int programNumber;
+    };
+
+    bool loadSoundfont(const std::string& filepath);
+    bool loadProgram(const Program& program);
+
+    bool setTuning(const std::array<double, NUM_MIDI_NOTES>& pitches);
+    bool resetTuning();
+
+    const std::vector<Program>& getPrograms() const;
+
+    // TODO JMT: remove this
+    fluid_synth_t* getSynth();
+
+private:
+
+
+    std::vector<Soundfont> soundfonts;
+    std::vector<Program> programs;
+
+    fluid_settings_t* settings = NULL;
+    fluid_synth_t* synth = NULL;
+    fluid_audio_driver_t* adriver = NULL;
+};