Initial commit: RMX-19 rack sound module (VST3/AU) with dot-matrix LCD UI

Source/SynthEngine.h

@@ -0,0 +1,144 @@
+#pragma once
+#include <juce_audio_processors/juce_audio_processors.h>
+#include "Params.h"
+
+struct VParams
+{
+    float osc1w = 2, osc2w = 3, detune = 8, oscMix = 52.f;
+    float fltType = 1, fltCut = 3400.f, fltRes = 0.18f, fltEnv = 52.f, fltKey = 40.f;
+    float ampA = 0.008f, ampD = 0.26f, ampS = 0.70f, ampR = 0.35f;
+    float fA = 0.02f, fD = 0.16f, fS = 0.26f, fR = 0.25f;
+    float lfoRate = 4.2f, lfoShape = 0, lfoDepth = 0.22f, lfoTarget = 0;
+    float fxType = 1, fxAmt = 0.30f, fxTime = 0.28f;
+    float vol = 0.85f, pan = 0.0f, poly = 10.f, glide = 0.f, tune = 0.f;
+
+    void update (const juce::AudioProcessorValueTreeState& apvts)
+    {
+        auto get = [&] (const char* id) { return apvts.getRawParameterValue (id) -> load(); };
+        osc1w    = get ("osc1wave"); osc2w = get ("osc2wave"); detune = get ("detune");
+        oscMix   = get ("oscmix");
+        fltType  = get ("flttype");  fltCut = get ("fltcut"); fltRes = get ("fltres");
+        fltEnv   = get ("fltenv");   fltKey = get ("fltkey");
+        ampA     = get ("ampA");     ampD = get ("ampD");     ampS = get ("ampS");
+        ampR     = get ("ampR");
+        fA       = get ("fenvA");    fD = get ("fenvD");      fS = get ("fenvS");
+        fR       = get ("fenvR");
+        lfoRate  = get ("lforate");  lfoShape = get ("lfoshape"); lfoDepth = get ("lfodepth");
+        lfoTarget= get ("lfotarget");
+        fxType   = get ("fxtype");   fxAmt = get ("fxamt");   fxTime = get ("fxtime");
+        vol      = get ("vol");      pan = get ("pan");       poly = get ("poly");
+        glide    = get ("glide");    tune = get ("tune");
+    }
+};
+
+// ---------------------------------------------------------------------------
+
+class Env
+{
+public:
+    enum State { Off, Atk, Dec, Sus, Rel };
+
+    void setRates (float a, float d, float s, float r, double sr)
+    {
+        srInv = 1.0 / sr;
+        attTau = 1.0f / (0.001f + 0.25f * a);
+        decTau = 1.0f / (0.001f + 0.35f * d);
+        relTau = 1.0f / (0.001f + 0.30f * r);
+        susL = s;
+    }
+
+    void noteOn () { st = Atk; }
+
+    void noteOff ()
+    {
+        if (st != Off && st != Rel) st = Rel;
+    }
+
+    void reset (float v = 0.0f) { cur = v; st = Off; }
+
+    float next()
+    {
+        switch (st)
+        {
+            case Atk:
+                cur += (1.0f - cur) * std::min (1.0f, (float) (attTau * srInv) * 8.0f);
+                if (cur >= 1.0f) { cur = 1.0f; st = Dec; }
+                break;
+            case Dec:
+                cur = susL + (cur - susL) * std::exp (-decTau * (float) srInv);
+                if (std::abs (cur - susL) < 0.001f) { cur = susL; st = Sus; }
+                break;
+            case Sus: break;
+            case Rel:
+                cur *= std::exp (-relTau * (float) srInv);
+                if (cur < 0.0002f) { cur = 0.0f; st = Off; }
+                break;
+            case Off: break;
+        }
+        return cur;
+    }
+
+    bool running() const     { return st != Off; }
+    float getCur() const     { return cur; }
+    State getState() const   { return st; }
+
+private:
+    float cur = 0.0f, susL = 0.7f;
+    float attTau = 1.0f, decTau = 1.0f, relTau = 1.0f;
+    double srInv = 1.0 / 48000.0;
+    State st = Off;
+};
+
+// ---------------------------------------------------------------------------
+
+class SynthEngine
+{
+public:
+    SynthEngine();
+    ~SynthEngine();
+
+    void setSampleRate (double sr);
+    void noteOn  (int midiNote, float velocity);
+    void noteOff (int midiNote);
+    void allNotesOff (bool immediate);
+    void sustainPedal (bool down);
+    void pitchBend (float cents);
+    void modWheel (float v);
+
+    void render (const VParams& p, float* left, float* right, int numSamples);
+
+    int  activeVoices() const noexcept  { return active; }
+    void getMeters (float& l, float& r) const noexcept { l = metL; r = metR; }
+
+private:
+    struct Voice
+    {
+        bool  active = false;
+        int   note = 0;
+        float vel = 1.0f;
+        float panL = 0.71f, panR = 0.71f;
+        float curFreq = 0.0f, targetFreq = 0.0f;
+        double ph1 = 0.0, ph2 = 0.0, lfoPh = 0.0;
+        float lfoSH = 0.0f;
+        int   lfoIdx = 0;
+        Env amp, flt;
+        float lp = 0.0f, bp = 0.0f, f1c = 0.0f;
+        float outSmooth = 0.0f;
+    };
+
+    static constexpr int maxVoice = 16;
+    Voice voices[maxVoice];
+    double sr = 48000.0;
+    int active = 0;
+    int polyLimit = 16;
+    float mod = 0.0f, bendCents = 0.0f, bendSmooth = 0.0f;
+    bool pedal = false;
+    float lastNoteFreq = 440.0f, lastGlide = 0.0f, lastPan = 0.0f;
+    int stealIdx = 0;
+    float metL = 0.0f, metR = 0.0f;
+    juce::Random rng;
+    juce::Array<int> sustainedNotes;
+
+    float osc (int wave, double ph);
+    Voice* acquireVoice();
+};