naive saw voice

plugin/chassis.cpp

@@ -69,10 +69,9 @@ void Chassis::noteOn(uint8_t note) {
     uint32_t i;
     for (i = 0; i < NUM_VOICES; i++) {
         // printf("note on, finding free voice in %02x for %d\n", assign[i], note);
-        if (voice[i].state == V_OFF) {  // top bit is voice free flag
-            voice[i].state = V_ON;      // enable
-            voice[i].note = note;
-            printf("voice %d set to note %d\n", i, note);
+        if (voice[i].isFree()) {  // top bit is voice free flag
+            voice[i].voiceOn(note);
+            //printf("voice %d set to note %d\n", i, note);
             break;
         }
     }
@@ -80,36 +79,38 @@ void Chassis::noteOn(uint8_t note) {
         // Voice v = voice[0];
         memmove(voice, voice + 1, sizeof(Voice) * (NUM_VOICES - 1));  // shunt all voices down by one
         // lessvoice[NUM_VOICES - 1] = v;                                    // oldest voice goes at the top of the queue
-        voice[NUM_VOICES - 1].note = note;  // set note, assume state is still set
-        printf("no free voices, reused %d for note %d\n", 0, note);
+        voice[NUM_VOICES - 1].voiceOn(note); // FIXME distinguish between restarting reused note and stolen note
+        //printf("no free voices, note %d\n", 0, note);
     }
-
+/*
     printf("note table is now\n");
     for (i = 0; i < NUM_VOICES; i++) {
-        printf("%2d = %3d %01x\n", i, voice[i].note, voice[i].state);
+        printf("%2d = %3d %s\n", i, voice[i].note, voice[i].isFree()?"off":"on ");
     }
     printf("----------------------------\n");
+    */
 }
 
 void Chassis::noteOff(uint8_t note) {
     uint32_t v;
-    printf("note off called for %3d\n", note);
+    //printf("note off called for %3d\n", note);
 
-    printf("trying voice ");
+    //printf("trying voice ");
     for (uint32_t i = 0; i < NUM_VOICES; i++) {
-        printf("%02x ", i);
+        //printf("%02x ", i);
 
-        if (voice[i].note == note && voice[i].state != V_OFF) {
-            printf("note off for %d playing %02x\n", i, note);
+        if (voice[i].note == note && !voice[i].isFree()) {
+           // printf("note off for %d playing %3d\n", i, note);
             //memmove(voice + i, voice + i + 1, sizeof(Voice) * (NUM_VOICES - i));
-            voice[i].state = V_OFF;
+            voice[i].voiceOff();
             break;
         }
     }
+    /*
     printf("\n note table is now\n");
     for (uint32_t i = 0; i < NUM_VOICES; i++) {
-        printf("%2d = %3d %01x\n", i, voice[i].note, voice[i].state);
-    }
+        printf("%2d = %3d %s\n", i, voice[i].note, voice[i].isFree()?"off":"on ");
+    }*/
 }
 
 void Chassis::run(const float **, float **outputs, uint32_t frames, const MidiEvent *MidiEvents, uint32_t midiEventCount) {
@@ -123,6 +124,14 @@ void Chassis::run(const float **, float **outputs, uint32_t frames, const MidiEv
             noteOff(MidiEvents[i].data[1]);
         }
     }
+
+    // run each synth voice
+    bzero(outputs[0], sizeof(float)*frames);
+    for (uint8_t i = 0; i < NUM_VOICES; i++) {
+        voice[i].run(outputs[0], frames);
+    }
+    // copy left to right
+    memmove(outputs[1], outputs[0], sizeof(float)*frames);
 }
 
 // create the plugin

plugin/chassis.hpp

@@ -19,12 +19,11 @@
 #ifndef _CHASSIS_HPP
 #define _CHASSIS_HPP
 
-#define NUM_VOICES 8
+#define NUM_VOICES 4
 
 #include "DistrhoPlugin.hpp"
 #include "voice.hpp"
 
-
 START_NAMESPACE_DISTRHO
 
 class Chassis : public Plugin {
@@ -65,7 +64,7 @@ class Chassis : public Plugin {
 
    private:
     Voice voice[NUM_VOICES];
-    //uint32_t 
+    // uint32_t
 
     DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(Chassis);
 };

plugin/voice.hpp

@@ -16,21 +16,53 @@
    CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
 
-
 #ifndef _VOICE_HPP
 #define _VOICE_HPP
 
 #include <cstdint>
 
-    enum VoiceState {
-        V_OFF,
-        V_ON
-    };
-
 class Voice {
    public:
     uint8_t note;
-    VoiceState state = V_OFF;
+
+    void voiceOn(uint32_t key) {
+        keyState = K_ON;
+        envState = ATTACK;
+        note = key;
+        omega = (261.63 * powf(2, (note - 60)/12.0f))/48000.0f;
+        target = 1;
+    }
+
+    void voiceOff() {
+        keyState = K_OFF;
+        envState = RELEASE;
+        target = 0;
+    }
+
+    inline bool isFree() {
+        return keyState == K_OFF;
+    }
+
+    void run(float *buffer, uint32_t samples) {
+
+        env = ((target - env)*0.01) + env;
+        for (uint32_t i = 0; i < samples; i++) {
+            phase += omega;
+            if (phase > 1) phase -= 1;
+            buffer[i] += (0.5-phase) * env;
+        }
+    }
+
+   private:
+    enum { ATTACK,
+           DECAY,
+           SUSTAIN,
+           RELEASE } envState = RELEASE;
+    enum { K_OFF,
+           K_ON,
+           K_SUSTAIN } keyState = K_OFF;
+    float phase, omega;
+    float env, target;
 };
 
-#endif // _VOICE_HPP
+#endif  // _VOICE_HPP