piano roll grid editing

4 files changed, 202 insertions, 38 deletions

diff --git a/README b/README
index 06efed4..c6e8422 100644
--- a/README
+++ b/README
@@ -4,10 +4,10 @@ Music sequencer and audio editor
 Tech
 
 - kit           - https://guattari.tech/kit.git
+- stb           - https://github.com/nothings/stb.git
 - sokol_app     - https://github.com/floooh/sokol.git
 - nanovg        - https://github.com/memononen/nanovg.git
 - miniaudio     - https://github.com/mackron/miniaudio.git
-- portmidi      - https://github.com/PortMidi/portmidi.git
 
 
 Algorithms
diff --git a/TODO b/TODO
index 1434ad6..795ab11 100644
--- a/TODO
+++ b/TODO
@@ -8,6 +8,11 @@ To-Do list
 - Build: WebAssembly
 - Sound: Kick, snare, cymbal
 - UI: Track composing
+- Biquad filter
+- Fourier transform
+- UI: Spectrum view
+- UI: Wave view
+- Improve X11 startup time
 
 Done
 
diff --git a/source/saw/main.c b/source/saw/main.c
index 298eb2a..e65b5b9 100644
--- a/source/saw/main.c
+++ b/source/saw/main.c
@@ -29,10 +29,23 @@ enum {
   SAW_CHANNEL_COUNT = 2,
   SAW_SAMPLE_RATE   = 44100,
 
-  VOICE_COUNT    = 16,
-  PIANOROLL_SIZE = 40
+  VOICE_COUNT = 16,
+  ROLL_SIZE   = 40,
+  SHEET_SIZE  = 200
 };
 
+typedef struct {
+  i8  enabled;
+  i64 time;
+  i64 duration;
+  i64 pitch;
+} saw_sheet_note_t;
+
+typedef struct {
+  i64              rate;
+  saw_sheet_note_t notes[SHEET_SIZE];
+} saw_sheet_t;
+
 static struct NVGcontext *saw_nvg;
 static ma_device          saw_ma;
 
@@ -41,13 +54,21 @@ static i32 saw_mouse_y       = 0;
 static i8  saw_lbutton_click = 0;
 static i8  saw_lbutton_down  = 0;
 static i8  saw_rbutton_click = 0;
+static i8  saw_rbutton_down  = 0;
+
+static i8  saw_voice_on[VOICE_COUNT]       = { 0 };
+static i32 saw_voice_pitch[VOICE_COUNT]    = { 0 };
+static i64 saw_voice_time[VOICE_COUNT]     = { 0 };
+static f64 saw_voice_duration[VOICE_COUNT] = { 0 };
 
-static i8  saw_voice_on[VOICE_COUNT]    = { 0 };
-static i32 saw_voice_pitch[VOICE_COUNT] = { 0 };
-static i64 saw_voice_time[VOICE_COUNT]  = { 0 };
+static i32         saw_roll_last_index            = -1;
+static i8          saw_roll_turned_off[ROLL_SIZE] = { 0 };
+static saw_sheet_t saw_roll_sheet = { .rate = 4, .notes = { 0 } };
 
-static i32 saw_pianoroll_last_index                 = -1;
-static i8  saw_pianoroll_turned_off[PIANOROLL_SIZE] = { 0 };
+static i8  saw_grid_input = 0;
+static i32 saw_grid_note  = 0;
+static i32 saw_grid_pitch = 0;
+static i32 saw_grid_time  = 0;
 
 #ifdef __GNUC__
 #  pragma GCC diagnostic push
@@ -90,19 +111,28 @@ static void saw_audio(ma_device *device, void *void_out_,
       continue;
 
     f64 period    = M_PI * 2.;
-    f64 frequency = pow(2., 7 + saw_voice_pitch[n] / 12.);
+    f64 frequency = pow(2., 7.3 + saw_voice_pitch[n] / 12.);
+    f64 amplitude = .2;
+
+    //  envelope
+    f64 attack   = .007;
+    f64 decay    = .2;
+    f64 sustain  = .2;
+    f64 duration = saw_voice_duration[n];
+    f64 release  = .4;
 
     for (i64 i = 0; i < frame_count; i++) {
-      f64 t         = (f64) saw_voice_time[n] / (f64) SAW_SAMPLE_RATE;
-      f64 amplitude = .4 * saw_envelope(t, .007, .2, .2, .6, .4);
-      f64 k         = period * frequency;
+      f64 t = (f64) saw_voice_time[n] / (f64) SAW_SAMPLE_RATE;
+      f64 a = amplitude * saw_envelope(t, attack, decay, sustain,
+                                       duration, release);
+      f64 k = period * frequency;
 
-      out[i * 2] += (f32) (sin(k * t) * amplitude);
-      out[i * 2 + 1] += (f32) (sin(k * t) * amplitude);
+      out[i * 2] += (f32) (sin(k * t) * a);
+      out[i * 2 + 1] += (f32) (sin(k * t) * a);
 
       saw_voice_time[n]++;
 
-      if (t > 1.0)
+      if (t > duration + release)
         saw_voice_on[n] = 0;
     }
   }
@@ -151,7 +181,7 @@ static void saw_frame(void) {
 
   nvgBeginFrame(saw_nvg, width, height, sapp_dpi_scale());
 
-  //  Draw piano roll
+  //  Piano roll
   //
 
   i32 x0 = 20;
@@ -159,15 +189,18 @@ static void saw_frame(void) {
 
   i32 pianokey_height = 40;
   i32 pianokey_width  = 100;
-  i32 pianokey_border = 2;
+  i32 roll_border     = 2;
+
+  i32 sheet_offset = 40;
+  i32 sheet_scale  = 20;
 
   i8 hover_any = 0;
 
-  for (i32 i = 0; i < PIANOROLL_SIZE; i++) {
-    i32 x = x0 + pianokey_border;
-    i32 y = height - y0 - (i + 1) * pianokey_height;
-    i32 w = pianokey_width - pianokey_border * 2;
-    i32 h = pianokey_height - pianokey_border * 2;
+  for (i32 pitch = 0; pitch < ROLL_SIZE; pitch++) {
+    i32 x = x0 + roll_border;
+    i32 y = height - y0 - (pitch + 1) * pianokey_height + roll_border;
+    i32 w = pianokey_width - roll_border * 2;
+    i32 h = pianokey_height - roll_border * 2;
 
     if (y > height - pianokey_height)
       continue;
@@ -180,39 +213,164 @@ static void saw_frame(void) {
     i8 has_cursor = saw_mouse_x >= x && saw_mouse_x < x + w &&
                     saw_mouse_y >= y && saw_mouse_y < y + h;
 
-    nvgFillColor(saw_nvg, saw_pianoroll_turned_off[i]
+    nvgFillColor(saw_nvg, saw_roll_turned_off[pitch]
                               ? nvgRGBA(220, 220, 220, 160)
                           : has_cursor ? nvgRGBA(200, 200, 255, 255)
                                        : nvgRGBA(220, 220, 220, 255));
     nvgFill(saw_nvg);
 
+    //  Piano roll input
+    //
+
     if (has_cursor) {
       hover_any = 1;
 
-      if (!saw_pianoroll_turned_off[i] &&
+      if (!saw_roll_turned_off[pitch] &&
           (saw_lbutton_click ||
-           (saw_lbutton_down && saw_pianoroll_last_index != i)) &&
+           (saw_lbutton_down && saw_roll_last_index != pitch)) &&
           !saw_voice_on[VOICE_COUNT - 1]) {
         for (i32 n = VOICE_COUNT - 1; n > 0; --n) {
-          saw_voice_on[n]    = saw_voice_on[n - 1];
-          saw_voice_pitch[n] = saw_voice_pitch[n - 1];
-          saw_voice_time[n]  = saw_voice_time[n - 1];
+          saw_voice_on[n]       = saw_voice_on[n - 1];
+          saw_voice_pitch[n]    = saw_voice_pitch[n - 1];
+          saw_voice_time[n]     = saw_voice_time[n - 1];
+          saw_voice_duration[n] = saw_voice_duration[n - 1];
         }
 
-        saw_voice_on[0]    = 1;
-        saw_voice_pitch[0] = i;
-        saw_voice_time[0]  = 0;
+        saw_voice_on[0]       = 1;
+        saw_voice_pitch[0]    = pitch;
+        saw_voice_time[0]     = 0;
+        saw_voice_duration[0] = .6;
       }
 
       if (saw_rbutton_click)
-        saw_pianoroll_turned_off[i] = !saw_pianoroll_turned_off[i];
+        saw_roll_turned_off[pitch] = !saw_roll_turned_off[pitch];
 
-      saw_pianoroll_last_index = i;
+      saw_roll_last_index = pitch;
     }
   }
 
   if (!hover_any)
-    saw_pianoroll_last_index = -1;
+    saw_roll_last_index = -1;
+
+  //  Draw music sheet
+  //
+
+  for (i32 pitch = 0; pitch < ROLL_SIZE; pitch++) {
+    i32 y = height - y0 - (pitch + 1) * pianokey_height;
+
+    if (y > height - pianokey_height)
+      continue;
+    if (y < 0)
+      break;
+
+    i32 h = pianokey_height;
+
+    for (i32 t = 0;; t++) {
+      i32 x = x0 + pianokey_width + sheet_offset + t * sheet_scale;
+
+      if (x >= width - roll_border)
+        break;
+
+      i32 note = -1;
+
+      for (i32 n = 0; n < SHEET_SIZE; n++) {
+        saw_sheet_note_t *p = saw_roll_sheet.notes + n;
+        if (p->enabled && p->pitch == pitch && t >= p->time &&
+            t < p->time + p->duration) {
+          note = n;
+          break;
+        }
+      }
+
+      i8 has_cursor = 0;
+
+      if (note == -1) {
+        //  Draw empty cell
+        //
+
+        i32 w = sheet_scale;
+
+        nvgBeginPath(saw_nvg);
+        nvgRect(saw_nvg, x + roll_border, y + roll_border,
+                w - roll_border * 2, h - roll_border * 2);
+
+        has_cursor = saw_mouse_x >= x && saw_mouse_x < x + w &&
+                     saw_mouse_y >= y && saw_mouse_y < y + h;
+
+        nvgFillColor(saw_nvg, saw_roll_turned_off[pitch]
+                                  ? nvgRGBA(180, 180, 180, 120)
+                              : has_cursor
+                                  ? nvgRGBA(180, 180, 220, 160)
+                                  : nvgRGBA(180, 180, 180, 160));
+        nvgFill(saw_nvg);
+
+        //  Empty cell input
+        //
+
+        if (!saw_grid_input && !saw_roll_turned_off[pitch] &&
+            has_cursor && saw_lbutton_click) {
+          for (i32 n = 0; n < SHEET_SIZE; n++)
+            if (!saw_roll_sheet.notes[n].enabled) {
+              saw_roll_sheet.notes[n] = (saw_sheet_note_t) {
+                .enabled = 1, .time = t, .duration = 1, .pitch = pitch
+              };
+              saw_grid_input = 1;
+              saw_grid_note  = n;
+              saw_grid_pitch = pitch;
+              saw_grid_time  = t;
+              break;
+            }
+        }
+      } else {
+        i32 w = sheet_scale * saw_roll_sheet.notes[note].duration;
+
+        has_cursor = saw_mouse_x >= x && saw_mouse_x < x + w &&
+                     saw_mouse_y >= y && saw_mouse_y < y + h;
+
+        if (t == saw_roll_sheet.notes[note].time) {
+          //  Draw note
+          //
+
+          nvgBeginPath(saw_nvg);
+          nvgRect(saw_nvg, x + roll_border, y + roll_border,
+                  w - roll_border * 2, h - roll_border * 2);
+
+          nvgFillColor(saw_nvg, has_cursor
+                                    ? nvgRGBA(180, 180, 220, 255)
+                                    : nvgRGBA(180, 180, 180, 255));
+          nvgFill(saw_nvg);
+
+          //  Note input
+          //
+
+          if (has_cursor && saw_rbutton_down)
+            saw_roll_sheet.notes[note].enabled = 0;
+        }
+      }
+    }
+
+    //  Note stretching
+    //
+
+    if (saw_grid_input) {
+      if (saw_lbutton_down) {
+        i32 t = (saw_mouse_x - x0 - pianokey_width - sheet_offset) /
+                sheet_scale;
+
+        if (t >= 0) {
+          saw_sheet_note_t *p = saw_roll_sheet.notes + saw_grid_note;
+          if (saw_grid_time <= t) {
+            p->time     = saw_grid_time;
+            p->duration = 1 + t - saw_grid_time;
+          } else {
+            p->time     = t;
+            p->duration = saw_grid_time - t;
+          }
+        }
+      } else
+        saw_grid_input = 0;
+    }
+  }
 
   nvgEndFrame(saw_nvg);
 
@@ -241,13 +399,15 @@ static void saw_event(sapp_event const *event) {
       break;
 
     case SAPP_EVENTTYPE_MOUSE_DOWN:
-
       switch (event->mouse_button) {
         case SAPP_MOUSEBUTTON_LEFT:
           saw_lbutton_down  = 1;
           saw_lbutton_click = 1;
           break;
-        case SAPP_MOUSEBUTTON_RIGHT: saw_rbutton_click = 1; break;
+        case SAPP_MOUSEBUTTON_RIGHT:
+          saw_rbutton_down  = 1;
+          saw_rbutton_click = 1;
+          break;
         default:;
       }
       break;
@@ -255,6 +415,7 @@ static void saw_event(sapp_event const *event) {
     case SAPP_EVENTTYPE_MOUSE_UP:
       switch (event->mouse_button) {
         case SAPP_MOUSEBUTTON_LEFT: saw_lbutton_down = 0; break;
+        case SAPP_MOUSEBUTTON_RIGHT: saw_rbutton_down = 0; break;
         default:;
       }
       break;
diff --git a/source/saw/profiler.h b/source/saw/profiler.h
index a4e0f9f..850b2e8 100644
--- a/source/saw/profiler.h
+++ b/source/saw/profiler.h
@@ -1,8 +1,6 @@
 #ifndef SAW_PROFILER_H
 #define SAW_PROFILER_H
 
-extern long long profiler_time_;
-
 void profile_frame(char const *s);
 
 #endif