initial implementation of polyphony using variable length array of notes on

3 files changed, 201 insertions, 2 deletions

diff --git a/quantum/process_keycode/process_midi.c b/quantum/process_keycode/process_midi.c
index 577dad43a..bc48b3905 100644
--- a/quantum/process_keycode/process_midi.c
+++ b/quantum/process_keycode/process_midi.c
@@ -1,10 +1,204 @@
 #include "process_midi.h"
 
+#if 0
 bool midi_activated = false;
 uint8_t midi_starting_note = 0x0C;
 int midi_offset = 7;
+#endif
+
+typedef union {
+  uint16_t raw;
+  struct {
+    uint8_t octave   :4;
+    uint8_t velocity :4;
+    uint8_t channel  :4;
+  };
+} midi_config_t;
+
+midi_config_t midi_config;
+
+#define MIDI_INVALID_NOTE 0xFF
+
+#if 0
+typedef struct {
+    uint64_t low;
+    uint64_t high;
+} uint128_t;
+
+#if 0
+static void right_shift_uint128_t(uint128_t* val, uint8_t shift)
+{
+    uint64_t high_mask = ~0 >> (64 - shift);
+    uint64_t high_bits = (val->high & high_mask) << (64 - shift);
+    val->high = val->high >> shift;
+    val->low = (val->low >> shift) | high_bits;
+}
+#endif
+
+static uint64_t left_shift_uint64_t(uint64_t val, uint8_t shift)
+{
+    dprintf("left_shift_uint64_t(val, %c) ...\n", val, shift);
+    while (shift > 16u) {
+        dprintf("  left_shift_uint64_t: val=?, shift=%c\n", val, shift);
+        val <<= 16;
+        shift -= 16;
+    }
+    dprintf("  left_shift_uint64_t: val=?, shift=%c\n", val, shift);
+    val <<= shift;
+    return val;
+}
+
+static void set_bit_uint128_t(uint128_t* val, uint8_t shift)
+{
+    uint64_t x = 1u;
+
+    if (shift < 64)
+    {
+        x = left_shift_uint64_t(x, shift);
+        dprintf("x: %d\n", x);
+        dprintf("set_bit_uint128_t (%d): 0x%016X%016X\n", shift, 0, x);
+        val->low = val->low | left_shift_uint64_t(1u, shift);
+    }
+    else
+    {
+        x = left_shift_uint64_t(x, shift - 64);
+        dprintf("set_bit_uint128_t (%d): 0x%016X%016X\n", shift, x, 0);
+        val->high = val->high | left_shift_uint64_t(1u, shift - 64);
+    }
+}
+
+static void clear_bit_uint128_t(uint128_t* val, uint8_t shift)
+{
+    if (shift < 64)
+    {
+        val->low = val->low & ~left_shift_uint64_t(1u, shift);
+    }
+    else
+    {
+        val->high = val->high & ~left_shift_uint64_t(1u, shift - 64);
+    }
+}
 
-bool process_midi(uint16_t keycode, keyrecord_t *record) {
+static bool is_bit_set_uint128_t(const uint128_t* val, uint8_t shift)
+{
+    if (shift < 64)
+    {
+        return !!(val->low & (1u << shift));
+    }
+    else
+    {
+        return !!(val->high & (1u << (shift - 64)));
+    }
+}
+
+uint128_t note_status = { 0, 0 };
+#endif
+
+
+#define MIDI_MAX_NOTES_ON 10
+
+typedef struct {
+    uint8_t note;
+    uint8_t tone;
+} midi_notes_on_array_entry_t;
+
+typedef struct {
+    uint8_t length;
+    midi_notes_on_array_entry_t values[MIDI_MAX_NOTES_ON];
+} midi_notes_on_array_t;
+
+static midi_notes_on_array_t notes_on;
+
+inline uint8_t compute_velocity(uint8_t setting)
+{
+    return (setting + 1) * (128 / (MIDI_VELOCITY_MAX - MIDI_VELOCITY_MIN + 1));
+}
+
+void midi_init(void)
+{
+    midi_config.octave = MI_OCT_0 - MIDI_OCTAVE_MIN;
+    midi_config.velocity = (MIDI_VELOCITY_MAX - MIDI_VELOCITY_MIN);
+    midi_config.channel = 0;
+    notes_on.length = 0;
+}
+
+bool process_midi(uint16_t keycode, keyrecord_t *record)
+{
+    switch (keycode) {
+        case MIDI_TONE_MIN ... MIDI_TONE_MAX:
+        {
+            uint8_t channel = midi_config.channel;
+            uint8_t tone = keycode - MIDI_TONE_MIN;
+            uint8_t velocity = compute_velocity(midi_config.velocity);
+            if (record->event.pressed && notes_on.length < MIDI_MAX_NOTES_ON) {
+                uint8_t note = 12 * midi_config.octave + tone;
+                midi_send_noteon(&midi_device, channel, note, velocity);
+                dprintf("midi noteon channel:%d note:%d velocity:%d\n", channel, note, velocity);
+                notes_on.values[notes_on.length].note = note;
+                notes_on.values[notes_on.length].tone = tone;
+                notes_on.length++;
+            }
+            else {
+                for (uint8_t i = 0; i < notes_on.length; i++) {
+                    uint8_t note = notes_on.values[i].note;
+                    if (tone == notes_on.values[i].tone) {
+                        midi_send_noteoff(&midi_device, channel, note, velocity);
+                        dprintf("midi noteoff channel:%d note:%d velocity:%d\n", channel, note, velocity);
+
+                        for (uint8_t j=i; j < notes_on.length - 1; j++)
+                        {
+                            notes_on.values[j] = notes_on.values[j + 1];
+                        }
+
+                        notes_on.length--;
+                        break;
+                    }
+                }
+            }
+            return false;
+        }
+        case MIDI_OCTAVE_MIN ... MIDI_OCTAVE_MAX:
+            if (record->event.pressed)
+                midi_config.octave = keycode - MIDI_OCTAVE_MIN;
+            return false;
+        case MI_OCTD:
+            if (record->event.pressed && midi_config.octave > 0)
+                midi_config.octave--;
+            return false;
+        case MI_OCTU:
+            if (record->event.pressed && midi_config.octave < (MIDI_OCTAVE_MAX - MIDI_OCTAVE_MIN))
+                midi_config.octave++;
+            return false;
+        case MIDI_VELOCITY_MIN ... MIDI_VELOCITY_MAX:
+            if (record->event.pressed)
+                midi_config.velocity = keycode - MIDI_VELOCITY_MIN;
+            return false;
+        case MI_VELD:
+            if (record->event.pressed && midi_config.velocity > 0)
+                midi_config.velocity--;
+            return false;
+        case MI_VELU:
+            if (record->event.pressed)
+                midi_config.velocity++;
+            return false;
+        case MIDI_CHANNEL_MIN ... MIDI_CHANNEL_MAX:
+            if (record->event.pressed)
+                midi_config.channel = keycode - MIDI_CHANNEL_MIN;
+            return false;
+        case MI_CHD:
+            if (record->event.pressed)
+                midi_config.channel--;
+            return false;
+        case MI_CHU:
+            if (record->event.pressed)
+                midi_config.channel++;
+            return false;
+        case MI_SUS:
+            //TODO
+            return false;
+    };
+
+#if 0
     if (keycode == MI_ON && record->event.pressed) {
       midi_activated = true;
 #ifdef AUDIO_ENABLE
@@ -64,5 +258,6 @@ bool process_midi(uint16_t keycode, keyrecord_t *record) {
       if (keycode < 0xFF) // ignores all normal keycodes, but lets RAISE, LOWER, etc through
         return false;
     }
-  return true;
+#endif
+    return true;
 }
diff --git a/quantum/process_keycode/process_midi.h b/quantum/process_keycode/process_midi.h
index acd4fc1b1..b0e0aeb83 100644
--- a/quantum/process_keycode/process_midi.h
+++ b/quantum/process_keycode/process_midi.h
@@ -2,6 +2,9 @@
 #define PROCESS_MIDI_H
 
 #include "quantum.h"
+#include "midi.h"
+
+void midi_init(void);
 
 bool process_midi(uint16_t keycode, keyrecord_t *record);
 
diff --git a/quantum/quantum_keycodes.h b/quantum/quantum_keycodes.h
index 3728fa366..a024a9639 100644
--- a/quantum/quantum_keycodes.h
+++ b/quantum/quantum_keycodes.h
@@ -189,6 +189,7 @@ enum quantum_keycodes {
     MI_VEL_1 = MIDI_VELOCITY_MIN,
     MI_VEL_2,
     MI_VEL_3,
+    MI_VEL_4,
     MI_VEL_5,
     MI_VEL_6,
     MI_VEL_7,