]> git.cworth.org Git - scherzo/blobdiff - scherzo.c
Rework computer keyboard input to be mapped piano keyboard
[scherzo] / scherzo.c
index 1f2fed753fae1aacefbd706b5cdfb7a5142dd9ad..e57ccbe9b3fe7f831d535bf73d77544d62dce04e 100644 (file)
--- a/scherzo.c
+++ b/scherzo.c
@@ -24,7 +24,7 @@
 #include "score.h"
 #include "mnemon.h"
 
-#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+#define ARRAY_SIZE(arr) ((int) (sizeof(arr) / sizeof(arr[0])))
 
 #define unused(foo) foo __attribute__((unused))
 
 
 typedef struct challenge
 {
+    int active;
     bin_t *bin;
     int item_index;
     score_staff_t *staff;
-    score_note_t *note;
+    pitch_t pitch;
 
     int satisfied;
     int mistaken;
 } challenge_t;
 
-typedef struct note_group
+typedef struct pitch_group
 {
     void *ctx;
-    score_note_t **notes;
+    pitch_t *pitches;
     int size;
-    int num_notes;
-} note_group_t;
+    int num_pitches;
+} pitch_group_t;
 
 typedef struct scherzo
 {
@@ -56,6 +57,7 @@ typedef struct scherzo
     GtkWidget *window;
     score_t *score;
     int staff_height;
+
     score_staff_t *treble;
     score_staff_t *bass;
     score_chord_t *chord;
@@ -64,7 +66,6 @@ typedef struct scherzo
      * keyboard". Any "piano keyboard" key knows its own octave and
      * accidental already. */
     int keyboard_octave;
-    pitch_accidental_t keyboard_accidental;
 
     int midi_fd;
     snd_midi_event_t *snd_midi_event;
@@ -72,18 +73,20 @@ typedef struct scherzo
     mnemon_t mnemon;
     challenge_t challenge;
 
-    note_group_t notes_pressed;
-    note_group_t notes_pedaled;
+    pitch_group_t notes_pressed;
+    pitch_group_t notes_pedaled;
 
     int pedal_pressed;
+
+    pitch_t key;
 } scherzo_t;
 
 /* Forward declarations. */
-static score_note_t *
-scherzo_press_note (scherzo_t *scherzo, pitch_t pitch, int octave);
+static void
+scherzo_press_note (scherzo_t *scherzo, pitch_t pitch);
 
 static void
-scherzo_release_note (scherzo_t *scherzo, pitch_t pitch, int octave);
+scherzo_release_note (scherzo_t *scherzo, pitch_t pitch);
 
 static void
 scherzo_press_pedal (scherzo_t *scherzo);
@@ -92,7 +95,7 @@ static void
 scherzo_release_pedal (scherzo_t *scherzo);
 
 static void
-_judge_note (scherzo_t *scherzo, score_note_t *note);
+_judge_pitch (scherzo_t *scherzo, pitch_t pitch);
 
 static void
 _score_challenge (scherzo_t *scherzo);
@@ -147,12 +150,10 @@ on_key_press_event (GtkWidget *widget,
 {
     scherzo_t *scherzo = user_data;
     int octave;
-    /* Initialize to keep the compiler quiet. */
-    pitch_name_t pitch_name = PITCH_C;
-    pitch_t pitch;
+    pitch_t pitch = PITCH_NOT_A_PITCH;
 
-    if (scherzo->challenge.note)
-       octave = scherzo->challenge.note->octave;
+    if (scherzo->challenge.active)
+       octave = PITCH_OCTAVE (scherzo->challenge.pitch);
     else
        octave = scherzo->keyboard_octave;
 
@@ -171,38 +172,89 @@ on_key_press_event (GtkWidget *widget,
        gtk_widget_queue_draw (widget);
        return TRUE;
        break;
-    case GDK_KEY_q:
-    case GDK_KEY_Q:
     case GDK_KEY_Escape:
        gtk_main_quit ();
        return FALSE;
-    case GDK_KEY_c:
-    case GDK_KEY_C:
-       pitch_name = PITCH_NAME_C;
+    /* Map a piano keyboard onto the computer keyboard with white keys
+     * along the home row, (piano C on computer A, up to next octave
+     * higher C on computer K). Black keys are in the expected
+     * positions, (C# is W, D# is E, etc.).
+     */
+    case GDK_KEY_a:
+    case GDK_KEY_A:
+       pitch = PITCH_LITERAL (C, NATURAL, octave);
+       break;
+    case GDK_KEY_s:
+    case GDK_KEY_S:
+       pitch = PITCH_LITERAL (D, NATURAL, octave);
        break;
     case GDK_KEY_d:
     case GDK_KEY_D:
-       pitch_name = PITCH_NAME_D;
-       break;
-    case GDK_KEY_e:
-    case GDK_KEY_E:
-       pitch_name = PITCH_NAME_E;
+       pitch = PITCH_LITERAL (E, NATURAL, octave);
        break;
     case GDK_KEY_f:
     case GDK_KEY_F:
-       pitch_name = PITCH_NAME_F;
+       pitch = PITCH_LITERAL (F, NATURAL, octave);
        break;
     case GDK_KEY_g:
     case GDK_KEY_G:
-       pitch_name = PITCH_NAME_G;
+       pitch = PITCH_LITERAL (G, NATURAL, octave);
        break;
-    case GDK_KEY_a:
-    case GDK_KEY_A:
-       pitch_name = PITCH_NAME_A;
+    case GDK_KEY_h:
+    case GDK_KEY_H:
+       pitch = PITCH_LITERAL (A, NATURAL, octave);
        break;
-    case GDK_KEY_b:
-    case GDK_KEY_B:
-       pitch_name = PITCH_NAME_B;
+    case GDK_KEY_j:
+    case GDK_KEY_J:
+       pitch = PITCH_LITERAL (B, NATURAL, octave);
+       break;
+    case GDK_KEY_k:
+    case GDK_KEY_K:
+       pitch = PITCH_LITERAL (C, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_l:
+    case GDK_KEY_L:
+       pitch = PITCH_LITERAL (D, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_semicolon:
+    case GDK_KEY_colon:
+       pitch = PITCH_LITERAL (E, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_apostrophe:
+    case GDK_KEY_quotedbl:
+       pitch = PITCH_LITERAL (F, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_w:
+    case GDK_KEY_W:
+       pitch = PITCH_LITERAL (C, SHARP, octave);
+       break;
+    case GDK_KEY_e:
+    case GDK_KEY_E:
+       pitch = PITCH_LITERAL (D, SHARP, octave);
+       break;
+    case GDK_KEY_t:
+    case GDK_KEY_T:
+       pitch = PITCH_LITERAL (F, SHARP, octave);
+       break;
+    case GDK_KEY_y:
+    case GDK_KEY_Y:
+       pitch = PITCH_LITERAL (G, SHARP, octave);
+       break;
+    case GDK_KEY_u:
+    case GDK_KEY_U:
+       pitch = PITCH_LITERAL (A, SHARP, octave);
+       break;
+    case GDK_KEY_o:
+    case GDK_KEY_O:
+       pitch = PITCH_LITERAL (C, SHARP, octave + 1);
+       break;
+    case GDK_KEY_p:
+    case GDK_KEY_P:
+       pitch = PITCH_LITERAL (D, SHARP, octave + 1);
+       break;
+    case GDK_KEY_bracketright:
+    case GDK_KEY_braceright:
+       pitch = PITCH_LITERAL (F, SHARP, octave + 1);
        break;
     case GDK_KEY_0:
     case GDK_KEY_1:
@@ -218,25 +270,12 @@ on_key_press_event (GtkWidget *widget,
     case GDK_KEY_space:
        scherzo_press_pedal (scherzo);
        break;
-    case GDK_KEY_Up:
-       if (scherzo->keyboard_accidental < PITCH_ACCIDENTAL_DOUBLE_SHARP)
-           scherzo->keyboard_accidental++;
-       break;
-    case GDK_KEY_Down:
-       if (scherzo->keyboard_accidental > PITCH_ACCIDENTAL_DOUBLE_FLAT)
-           scherzo->keyboard_accidental--;
-       break;
     }
 
-    pitch = PITCH (pitch_name, scherzo->keyboard_accidental);
-
-    if ((key->keyval >= GDK_KEY_A && key->keyval <= GDK_KEY_G) ||
-       (key->keyval >= GDK_KEY_a && key->keyval <= GDK_KEY_g))
+    if (pitch != PITCH_NOT_A_PITCH) 
     {
-       score_note_t *note;
-
-       note = scherzo_press_note (scherzo, pitch, octave);
-       _judge_note (scherzo, note);
+       scherzo_press_note (scherzo, pitch);
+       _judge_pitch (scherzo, pitch);
        gtk_widget_queue_draw (scherzo->window);
 
        return TRUE;
@@ -254,55 +293,98 @@ on_key_release_event (unused (GtkWidget *widget),
 {
     scherzo_t *scherzo = user_data;
     int octave;
-    /* Initialize to keep the compiler quiet. */
-    pitch_name_t pitch_name = PITCH_NAME_C;
-    pitch_t pitch;
+    pitch_t pitch = PITCH_NOT_A_PITCH;
 
-    if (scherzo->challenge.note)
-       octave = scherzo->challenge.note->octave;
+    if (scherzo->challenge.active)
+       octave = PITCH_OCTAVE (scherzo->challenge.pitch);
     else
        octave = scherzo->keyboard_octave;
 
     switch (key->keyval) {
-    case GDK_KEY_c:
-    case GDK_KEY_C:
-       pitch_name = PITCH_NAME_C;
+    case GDK_KEY_a:
+    case GDK_KEY_A:
+       pitch = PITCH_LITERAL (C, NATURAL, octave);
+       break;
+    case GDK_KEY_s:
+    case GDK_KEY_S:
+       pitch = PITCH_LITERAL (D, NATURAL, octave);
        break;
     case GDK_KEY_d:
     case GDK_KEY_D:
-       pitch_name = PITCH_NAME_D;
-       break;
-    case GDK_KEY_e:
-    case GDK_KEY_E:
-       pitch_name = PITCH_NAME_E;
+       pitch = PITCH_LITERAL (E, NATURAL, octave);
        break;
     case GDK_KEY_f:
     case GDK_KEY_F:
-       pitch_name = PITCH_NAME_F;
+       pitch = PITCH_LITERAL (F, NATURAL, octave);
        break;
     case GDK_KEY_g:
     case GDK_KEY_G:
-       pitch_name = PITCH_NAME_G;
+       pitch = PITCH_LITERAL (G, NATURAL, octave);
        break;
-    case GDK_KEY_a:
-    case GDK_KEY_A:
-       pitch_name = PITCH_NAME_A;
+    case GDK_KEY_h:
+    case GDK_KEY_H:
+       pitch = PITCH_LITERAL (A, NATURAL, octave);
        break;
-    case GDK_KEY_b:
-    case GDK_KEY_B:
-       pitch_name = PITCH_NAME_B;
+    case GDK_KEY_j:
+    case GDK_KEY_J:
+       pitch = PITCH_LITERAL (B, NATURAL, octave);
+       break;
+    case GDK_KEY_k:
+    case GDK_KEY_K:
+       pitch = PITCH_LITERAL (C, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_l:
+    case GDK_KEY_L:
+       pitch = PITCH_LITERAL (D, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_semicolon:
+    case GDK_KEY_colon:
+       pitch = PITCH_LITERAL (E, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_apostrophe:
+    case GDK_KEY_quotedbl:
+       pitch = PITCH_LITERAL (F, NATURAL, octave + 1);
+       break;
+    case GDK_KEY_w:
+    case GDK_KEY_W:
+       pitch = PITCH_LITERAL (C, SHARP, octave);
+       break;
+    case GDK_KEY_e:
+    case GDK_KEY_E:
+       pitch = PITCH_LITERAL (D, SHARP, octave);
+       break;
+    case GDK_KEY_t:
+    case GDK_KEY_T:
+       pitch = PITCH_LITERAL (F, SHARP, octave);
+       break;
+    case GDK_KEY_y:
+    case GDK_KEY_Y:
+       pitch = PITCH_LITERAL (G, SHARP, octave);
+       break;
+    case GDK_KEY_u:
+    case GDK_KEY_U:
+       pitch = PITCH_LITERAL (A, SHARP, octave);
+       break;
+    case GDK_KEY_o:
+    case GDK_KEY_O:
+       pitch = PITCH_LITERAL (C, SHARP, octave + 1);
+       break;
+    case GDK_KEY_p:
+    case GDK_KEY_P:
+       pitch = PITCH_LITERAL (D, SHARP, octave + 1);
+       break;
+    case GDK_KEY_bracketright:
+    case GDK_KEY_braceright:
+       pitch = PITCH_LITERAL (F, SHARP, octave + 1);
        break;
     case GDK_KEY_space:
        scherzo_release_pedal (scherzo);
        break;
     }
 
-    pitch = PITCH (pitch_name, scherzo->keyboard_accidental);
-
-    if ((key->keyval >= GDK_KEY_A && key->keyval <= GDK_KEY_G) ||
-       (key->keyval >= GDK_KEY_a && key->keyval <= GDK_KEY_g))
+    if (pitch != PITCH_NOT_A_PITCH)
     {
-       scherzo_release_note (scherzo, pitch, octave);
+       scherzo_release_note (scherzo, pitch);
        _score_challenge (scherzo);
        gtk_widget_queue_draw (scherzo->window);
 
@@ -315,9 +397,9 @@ on_key_release_event (unused (GtkWidget *widget),
 }
 
 static unsigned char
-_pitch_and_octave_to_midi (pitch_t pitch,
-                                int octave)
+_pitch_to_midi (pitch_t pitch)
 {
+    int octave = PITCH_OCTAVE (pitch);
     unsigned char midi_note = 12 * (octave + 1);
 
     switch (PITCH_NAME (pitch)) {
@@ -364,80 +446,89 @@ _pitch_and_octave_to_midi (pitch_t pitch,
 }
 
 /* octave can optionally by NULL */
-static void
-_midi_to_pitch_and_octave (unsigned char midi_note,
-                                pitch_t *pitch,
-                                int *octave)
+static pitch_t
+_midi_to_pitch (unsigned char midi_note)
 {
-    if (octave)
-       *octave = midi_note / 12 - 1;
+    int octave = octave = midi_note / 12 - 1;
 
     switch (midi_note % 12)
     {
+    default:
     case 0:
-       *pitch = PITCH_C;
+       return PITCH_LITERAL (C, NATURAL, octave);
        break;
     case 1:
-       *pitch = PITCH_Cs;
+       return PITCH_LITERAL (C, SHARP, octave);
        break;
     case 2:
-       *pitch = PITCH_D;
+       return PITCH_LITERAL (D, NATURAL, octave);
        break;
     case 3:
-       *pitch = PITCH_Ds;
+       return PITCH_LITERAL (D, SHARP, octave);
        break;
     case 4:
-       *pitch = PITCH_E;
+       return PITCH_LITERAL (E, NATURAL, octave);
        break;
     case 5:
-       *pitch = PITCH_F;
+       return PITCH_LITERAL (F, NATURAL, octave);
        break;
     case 6:
-       *pitch = PITCH_Fs;
+       return PITCH_LITERAL (F, SHARP, octave);
        break;
     case 7:
-       *pitch = PITCH_G;
+       return PITCH_LITERAL (G, NATURAL, octave);
        break;
     case 8:
-       *pitch = PITCH_Gs;
+       return PITCH_LITERAL (G, SHARP, octave);
        break;
     case 9:
-       *pitch = PITCH_A;
+       return PITCH_LITERAL (A, NATURAL, octave);
        break;
     case 10:
-       *pitch = PITCH_As;
+       return PITCH_LITERAL (A, SHARP, octave);
        break;
     case 11:
-       *pitch = PITCH_B;
+       return PITCH_LITERAL (B, NATURAL, octave);
        break;
     }
 }
 
+/* Return true if 'a' and 'b' sound identical, (even if spelled differently)
+ *
+ * This comparison considers octaves as significant. So Bb and A# in
+ * the same octave are considered enharmonic, but Bb and A# in
+ * different octaves are not. */
+static int
+_pitches_are_enharmonic (pitch_t a, pitch_t b)
+{
+    return _pitch_to_midi (a) == _pitch_to_midi (b);
+}
+
 /* Determine a chord name (if any) from the current notes pressed */
 
-typedef struct analyzed_note {
+typedef struct analyzed_pitch {
     /* Original note being analzyed. */
-    score_note_t *note;
+    pitch_t pitch;
 
     /* Absolute pitch (expressed as midi number). */
     int midi_pitch;
 
     /* Pitch relative to bass note. */
     int relative_pitch;
-} analyzed_note_t;
+} analyzed_pitch_t;
 
 static int
-_compare_analyzed_note_by_midi_pitch (const void *va, const void *vb)
+_compare_analyzed_pitch_by_midi_pitch (const void *va, const void *vb)
 {
-    const analyzed_note_t *a = va, *b = vb;
+    const analyzed_pitch_t *a = va, *b = vb;
 
     return a->midi_pitch - b->midi_pitch;
 }
 
 static int
-_compare_analyzed_note_by_relative_pitch (const void *va, const void *vb)
+_compare_analyzed_pitch_by_relative_pitch (const void *va, const void *vb)
 {
-    const analyzed_note_t *a = va, *b = vb;
+    const analyzed_pitch_t *a = va, *b = vb;
 
     return a->relative_pitch - b->relative_pitch;
 }
@@ -492,27 +583,22 @@ _modified_degree_to_half_steps (const modified_degree_t *degree)
 }
 
 /* Number of half steps from 'root' up to 'pitch' (that is, counting
- * the steps up a chromatic scale). */
+ * the steps up a chromatic scale), within the same octave. */
 static int
 _pitch_from_root_in_half_steps (pitch_t pitch, pitch_t root)
 {
-    int root_midi = _pitch_and_octave_to_midi (root, 0);
-    int pitch_midi = _pitch_and_octave_to_midi (pitch, 0);
+    int root_midi = _pitch_to_midi (root);
+    int pitch_midi = _pitch_to_midi (pitch);
 
-    if (pitch_midi < root_midi)
+    while (pitch_midi < root_midi)
        pitch_midi += 12;
 
-    if (pitch_midi < root_midi) {
-       fprintf (stderr, "Internal error: midi values differ by more than expected.\n");
-       exit (1);
-    }
-
     return (pitch_midi - root_midi) % 12;
 }
 
 static int
-_chord_signature_matches (analyzed_note_t *notes,
-                         int num_notes,
+_chord_signature_matches (analyzed_pitch_t *pitches,
+                         int num_pitches,
                          modified_degree_t *degrees,
                          int num_degrees,
                          int inversion,
@@ -524,7 +610,7 @@ _chord_signature_matches (analyzed_note_t *notes,
 
     assert (num_degrees <= MAX_DEGREES);
 
-    if (num_notes != num_degrees)
+    if (num_pitches != num_degrees)
        return 0;
 
     if (inversion >= num_degrees)
@@ -547,96 +633,16 @@ _chord_signature_matches (analyzed_note_t *notes,
                
     }
 
-    for (i = 0; i < num_notes; i++)
-       if (notes[i].relative_pitch != relative_pitches[i])
+    for (i = 0; i < num_pitches; i++)
+       if (pitches[i].relative_pitch != relative_pitches[i])
            return 0;
 
-    root_index = (num_notes - inversion) % num_notes;
-    *root = notes[root_index].note->pitch;
+    root_index = (num_pitches - inversion) % num_pitches;
+    *root = pitches[root_index].pitch;
 
     return 1;
 }
 
-static const char *
-_pitch_str (pitch_t pitch)
-{
-    switch (pitch) {
-    case PITCH_Cff:
-       return "C𝄫";
-    case PITCH_Cf:
-       return "C♭";
-    case PITCH_C:
-       return "C";
-    case PITCH_Cs:
-       return "C♯";
-    case PITCH_Css:
-       return "C𝄪";
-    case PITCH_Dff:
-       return "D𝄫";
-    case PITCH_Df:
-       return "D♭";
-    case PITCH_D:
-       return "D";
-    case PITCH_Ds:
-       return "D♯";
-    case PITCH_Dss:
-       return "D𝄪";
-    case PITCH_Eff:
-       return "E𝄫";
-    case PITCH_Ef:
-       return "E♭";
-    case PITCH_E:
-       return "E";
-    case PITCH_Es:
-       return "E♯";
-    case PITCH_Ess:
-       return "E𝄪";
-    case PITCH_Fff:
-       return "F𝄫";
-    case PITCH_Ff:
-       return "F♭";
-    case PITCH_F:
-       return "F";
-    case PITCH_Fs:
-       return "F♯";
-    case PITCH_Fss:
-       return "F𝄪";
-    case PITCH_Gff:
-       return "G𝄫";
-    case PITCH_Gf:
-       return "G♭";
-    case PITCH_G:
-       return "G";
-    case PITCH_Gs:
-       return "G♯";
-    case PITCH_Gss:
-       return "G𝄪";
-    case PITCH_Aff:
-       return "A𝄫";
-    case PITCH_Af:
-       return "A♭";
-    case PITCH_A:
-       return "A";
-    case PITCH_As:
-       return "A♯";
-    case PITCH_Ass:
-       return "A𝄪";
-    case PITCH_Bff:
-       return "B𝄫";
-    case PITCH_Bf:
-       return "B♭";
-    case PITCH_B:
-       return "B";
-    case PITCH_Bs:
-       return "B♯";
-    case PITCH_Bss:
-       return "B𝄪";
-    }
-
-    fprintf (stderr, "Internal error: Unknown pitch %d\n", pitch);
-    exit (1);
-}
-
 typedef struct chord_signature
 {
     int num_degrees;
@@ -786,12 +792,13 @@ chord_signature_t signatures[] = {
 };
 
 static void
-scherzo_adjust_note_to_match_modified_degree (score_note_t *note,
-                                             pitch_t root,
-                                             modified_degree_t *degree)
+scherzo_adjust_pitch_to_match_modified_degree (pitch_t *pitch,
+                                              pitch_t root,
+                                              modified_degree_t *degree)
 {
-    pitch_name_t name = PITCH_NAME (note->pitch);
-    pitch_accidental_t accidental = PITCH_ACCIDENTAL (note->pitch);
+    pitch_name_t name = PITCH_NAME (*pitch);
+    pitch_accidental_t accidental = PITCH_ACCIDENTAL (*pitch);
+    int octave = PITCH_OCTAVE (*pitch);
     int degree_zero_based = (degree->degree - 1) % 7;
     int degree_delta;
 
@@ -816,7 +823,7 @@ scherzo_adjust_note_to_match_modified_degree (score_note_t *note,
     if (degree_delta == -1) {
        if (name == PITCH_NAME_B) {
            name = PITCH_NAME_C;
-           note->octave++;
+           octave++;
        } else {
            name++;
        }
@@ -838,7 +845,7 @@ scherzo_adjust_note_to_match_modified_degree (score_note_t *note,
     if (degree_delta == +1) {
        if (name == PITCH_NAME_C) {
            name = PITCH_NAME_B;
-           note->octave--;
+           octave--;
        } else {
            name--;
        }
@@ -861,12 +868,11 @@ scherzo_adjust_note_to_match_modified_degree (score_note_t *note,
        exit (1);
     }
 
-    note->pitch = PITCH (name, accidental);
+    *pitch = PITCH (name, accidental, octave);
 }
 
 static void
-_spell_chord_by_signature (note_group_t *chord,
-                          int num_notes,
+_spell_chord_by_signature (pitch_group_t *chord,
                           chord_signature_t *signature,
                           pitch_t root)
 {
@@ -875,18 +881,18 @@ _spell_chord_by_signature (note_group_t *chord,
 
     /* Sanitize root to eliminate things like double-flats,
      * double-sharps, Cb, E#, etc. */
-    root_midi = _pitch_and_octave_to_midi (root, 0);
-    _midi_to_pitch_and_octave (root_midi, &root, NULL);
+    root_midi = _pitch_to_midi (root);
+    root = _midi_to_pitch (root_midi);
     
-    for (i = 0; i < num_notes; i++) {
-       note_half_steps = _pitch_from_root_in_half_steps (chord->notes[i]->pitch,
+    for (i = 0; i < chord->num_pitches; i++) {
+       note_half_steps = _pitch_from_root_in_half_steps (chord->pitches[i],
                                                          root);
        for (degree = 0; degree < signature->num_degrees; degree++) {
            degree_half_steps = _modified_degree_to_half_steps (&signature->degrees[degree]);
            if (note_half_steps == degree_half_steps) {
-               scherzo_adjust_note_to_match_modified_degree (chord->notes[i],
-                                                             root,
-                                                             &signature->degrees[degree]);
+               scherzo_adjust_pitch_to_match_modified_degree (&chord->pitches[i],
+                                                              root,
+                                                              &signature->degrees[degree]);
                break;
            }
        }
@@ -898,68 +904,61 @@ _spell_chord_by_signature (note_group_t *chord,
 }
 
 static void
-scherzo_analyze_chord (scherzo_t *scherzo)
+_analyze_chord (pitch_group_t *chord,
+               chord_signature_t **signature_ret,
+               pitch_t **root_ret)
 {
     void *local = talloc_new (NULL);
-    analyzed_note_t *notes;
-    note_group_t *note_group;
-    unsigned i, j, num_notes;
+    analyzed_pitch_t *pitches;
+    int i, j, num_pitches;
     int bass_pitch, inversion;
     pitch_t root;
     chord_signature_t *match = NULL;
-    char *chord_name;
-
-    if (scherzo->pedal_pressed)
-       note_group = &scherzo->notes_pedaled;
-    else
-       note_group = &scherzo->notes_pressed;
 
-    num_notes = note_group->num_notes;
+    /* Default to no-match for any early return */
+    *signature_ret = NULL;
+    *root_ret = NULL;
 
-    if (scherzo->chord) {
-       score_remove_chord (scherzo->chord);
-       scherzo->chord = NULL;
-    }
+    num_pitches = chord->num_pitches;
 
-    if (num_notes <= 1)
+    if (chord->num_pitches <= 1)
        goto DONE;
 
-    notes = talloc_array (local, analyzed_note_t, num_notes);
-    if (notes == NULL)
+    pitches = talloc_array (local, analyzed_pitch_t, num_pitches);
+    if (pitches == NULL)
        goto DONE;
 
-    for (i = 0; i < num_notes; i++) {
-       score_note_t *note = note_group->notes[i];
-       notes[i].note = note;
-       notes[i].midi_pitch = _pitch_and_octave_to_midi (note->pitch,
-                                                              note->octave);
+    for (i = 0; i < num_pitches; i++) {
+       pitch_t pitch = chord->pitches[i];
+       pitches[i].pitch = pitch;
+       pitches[i].midi_pitch = _pitch_to_midi (pitch);
        /* Relative pitch will be filled in after sorting. */
-       notes[i].relative_pitch = 0;
+       pitches[i].relative_pitch = 0;
     }
 
     /* First, sort by midi pitch to find the bass note. */
-    qsort (notes, num_notes, sizeof (analyzed_note_t),
-          _compare_analyzed_note_by_midi_pitch);
+    qsort (pitches, num_pitches, sizeof (analyzed_pitch_t),
+          _compare_analyzed_pitch_by_midi_pitch);
     
-    bass_pitch = notes[0].midi_pitch;
+    bass_pitch = pitches[0].midi_pitch;
 
     /* With the bass note identified, we can find all relative pitches. */
-    for (i = 0; i < num_notes; i++) {
-       notes[i].relative_pitch = notes[i].midi_pitch - bass_pitch;
-       while (notes[i].relative_pitch >= 12)
-           notes[i].relative_pitch -= 12;
+    for (i = 0; i < num_pitches; i++) {
+       pitches[i].relative_pitch = pitches[i].midi_pitch - bass_pitch;
+       while (pitches[i].relative_pitch >= 12)
+           pitches[i].relative_pitch -= 12;
     }
 
     /* Now, sort again by relative pitch. */
-    qsort (notes, num_notes, sizeof (analyzed_note_t),
-          _compare_analyzed_note_by_relative_pitch);
+    qsort (pitches, num_pitches, sizeof (analyzed_pitch_t),
+          _compare_analyzed_pitch_by_relative_pitch);
 
     /* Finally, eliminate all duplicate notes. */
-    for (i = 0; i < num_notes - 1; i++) {
-           if (notes[i+1].relative_pitch == notes[i].relative_pitch) {
+    for (i = 0; i < num_pitches - 1; i++) {
+           if (pitches[i+1].relative_pitch == pitches[i].relative_pitch) {
                    j = i+1;
-                   while (j < num_notes &&
-                          notes[j].relative_pitch == notes[i].relative_pitch)
+                   while (j < num_pitches &&
+                          pitches[j].relative_pitch == pitches[i].relative_pitch)
                    {
                            j++;
                    }
@@ -969,18 +968,18 @@ scherzo_analyze_chord (scherzo_t *scherzo)
                     * the array bounds).*/
                    j--;
 
-                   if (j < num_notes - 1) {
-                           memmove (&notes[i+1], &notes[j+1],
-                                    (num_notes - j) * sizeof (analyzed_note_t));
+                   if (j < num_pitches - 1) {
+                           memmove (&pitches[i+1], &pitches[j+1],
+                                    (num_pitches - j) * sizeof (analyzed_pitch_t));
                    }
 
-                   num_notes -= (j - i);
+                   num_pitches -= (j - i);
            }
     }
 
     for (inversion = 0; inversion < 4; inversion++) {
        for (i = 0; i < ARRAY_SIZE (signatures); i++) {
-           if (_chord_signature_matches (notes, num_notes,
+           if (_chord_signature_matches (pitches, num_pitches,
                                          signatures[i].degrees,
                                          signatures[i].num_degrees,
                                          inversion, &root))
@@ -992,168 +991,205 @@ scherzo_analyze_chord (scherzo_t *scherzo)
     }
 HAVE_MATCH:
 
-    chord_name = (char *) signatures[i].name;
-
     if (match) {
-       /* Don't print root pitch for octaves and inversions,
-        * (since a pitch name alone looks like a major triad) */
-       if (num_notes < 3) {
-           chord_name = talloc_strdup (local, chord_name);
-       } else {
-           chord_name = talloc_asprintf (local, "%s%s",
-                                         _pitch_str (root),
-                                         chord_name);
+       *signature_ret = match;
+       for (i = 0; i < chord->num_pitches; i++) {
+           if (chord->pitches[i] == root) {
+               *root_ret = &chord->pitches[i];
+               break;
+           }
        }
-
-       _spell_chord_by_signature (note_group, num_notes,
-                                  match, root);
-    } else {
-       chord_name = talloc_strdup (local, "?");
     }
 
-    scherzo->chord = score_add_chord (scherzo->treble, chord_name);
-
 DONE:
     talloc_free (local);
 }
 
 static void
-note_group_init (void *ctx, note_group_t *group)
+pitch_group_init (void *ctx, pitch_group_t *group)
 {
     group->ctx = ctx;
-    group->notes = NULL;
+    group->pitches = NULL;
     group->size = 0;
-    group->num_notes = 0;
+    group->num_pitches = 0;
 }
 
 static void
-note_group_add_note (note_group_t *group, score_note_t *note)
+pitch_group_add_pitch (pitch_group_t *group, pitch_t pitch)
 {
     int i;
 
-    /* Do nothing if note is already in group. */
-    for (i = 0; i < group->num_notes; i++) {
-       if (group->notes[i]->pitch == note->pitch &&
-           group->notes[i]->octave == note->octave)
-       {
+    /* Do nothing if pitch is already in group. */
+    for (i = 0; i < group->num_pitches; i++)
+       if (group->pitches[i] == pitch)
            return;
-       }
-    }
 
-    group->num_notes++;
+    group->num_pitches++;
 
-    if (group->num_notes > group->size) {
+    if (group->num_pitches > group->size) {
        group->size++;
-       group->notes = talloc_realloc (group->ctx, group->notes,
-                                      score_note_t*, group->size);
+       group->pitches = talloc_realloc (group->ctx, group->pitches,
+                                        pitch_t, group->size);
 
-       if (group->notes == NULL) {
+       if (group->pitches == NULL) {
            fprintf (stderr, "Out of memory.\n");
            exit (1);
        }
     }
 
-    group->notes[group->num_notes - 1] = note;
+    group->pitches[group->num_pitches - 1] = pitch;
 }
 
 static void
-note_group_remove_note_at (note_group_t *group, int i)
+pitch_group_remove_pitch_at (pitch_group_t *group, int i)
 {
-    if (i >= group->num_notes) {
-       fprintf (stderr, "Internal error: No note to remove at index %d\n", i);
+    if (i > group->num_pitches) {
+       fprintf (stderr, "Internal error: Cannot remove pitch %d from group with only %d %s\n",
+                i, group->num_pitches,
+                group->num_pitches == 1 ? "pitch" : "pitches");
        exit (1);
     }
 
-    if (i < group->num_notes - 1) {
-       memmove (group->notes + i, group->notes + i + 1,
-                (group->num_notes - 1 - i) * sizeof (score_note_t*));
+    if (i < group->num_pitches - 1) {
+       memmove (group->pitches + i, group->pitches + i + 1,
+                (group->num_pitches - 1 - i) * sizeof (pitch_t));
     }
-    group->num_notes--;
+
+    group->num_pitches--;
 }
 
-static score_note_t *
-scherzo_press_note (scherzo_t *scherzo, pitch_t pitch, int octave)
+/* Remove a 'pitch' from 'group', (including any enharmonic pitch)
+ * See also: pitch_group_remove_pitch
+ */
+static void
+pitch_group_remove_pitch_enharmonic (pitch_group_t *group, pitch_t pitch)
 {
-    score_staff_t *staff;
-    score_note_t *note;
     int i;
 
-    if (scherzo->challenge.note) {
-       staff = scherzo->challenge.staff;
-    } else if (octave >= 4) {
-       staff = scherzo->treble;
-    } else {
-       staff = scherzo->bass;
-    }
-
-    /* Do nothing if this note is already pressed. */
-    for (i = 0; i < scherzo->notes_pressed.num_notes; i++) {
-       if (scherzo->notes_pressed.notes[i]->pitch == pitch &&
-           scherzo->notes_pressed.notes[i]->octave == octave)
-       {
-           return scherzo->notes_pressed.notes[i];
-       }
-    }
+    for (i = 0; i < group->num_pitches; i++)
+       if (_pitches_are_enharmonic (group->pitches[i], pitch))
+           pitch_group_remove_pitch_at (group, i);
+}
 
-    note = score_add_note (staff, pitch, octave, SCORE_DURATION_WHOLE);
+/* Remove an exactly-matching pitch from 'group'
+ * See also: pitch_group_remove_pitch_enharmonic
+ *
+static void
+pitch_group_remove_pitch (pitch_group_t *group, pitch_t pitch)
+{
+    int i;
 
-    note_group_add_note (&scherzo->notes_pressed, note);
+    for (i = 0; i < group->num_pitches; i++)
+       if (group->pitches[i] == pitch)
+           pitch_group_remove_pitch_at (group, i);
+}
+*/
 
-    if (scherzo->pedal_pressed)
-       note_group_add_note (&scherzo->notes_pedaled, note);
+static void
+scherzo_update_notes_and_chord (scherzo_t *scherzo)
+{
+    if (scherzo->notes_pressed.num_pitches == 0 &&
+       scherzo->notes_pedaled.num_pitches == 0)
+    {
+       score_remove_notes (scherzo->score);
 
-    scherzo_analyze_chord (scherzo);
+       score_remove_chords (scherzo->score);
 
-    return note;
+       gtk_widget_queue_draw (scherzo->window);
+    }
 }
 
 static void
-scherzo_release_note (scherzo_t *scherzo, pitch_t pitch, int octave)
+scherzo_press_note (scherzo_t *scherzo, pitch_t pitch)
 {
-    score_note_t *note;
+    void *local = talloc_new (NULL);
+    pitch_group_t *chord;
+    chord_signature_t *signature;
+    char *chord_name = NULL;
+    pitch_t *root;
     int i;
-    int found = 0;
-    int target_midi = _pitch_and_octave_to_midi (pitch, octave);
-    int note_midi;
-
-    for (i = scherzo->notes_pressed.num_notes - 1; i >=0; i--) {
-       note = scherzo->notes_pressed.notes[i];
-       note_midi = _pitch_and_octave_to_midi (note->pitch, note->octave);
-       if (note_midi == target_midi) {
-           found = 1;
-           if (! scherzo->pedal_pressed)
-               score_remove_note (note);
-           note_group_remove_note_at (&scherzo->notes_pressed, i);
+
+    /* Do nothing if this note is already pressed. */
+    for (i = 0; i < scherzo->notes_pressed.num_pitches; i++)
+       if (scherzo->notes_pressed.pitches[i] == pitch)
+           return;
+
+    pitch_group_add_pitch (&scherzo->notes_pressed, pitch);
+
+    if (scherzo->pedal_pressed)
+       pitch_group_add_pitch (&scherzo->notes_pedaled, pitch);
+
+    /* Remove all notes/chords from score, then add current notes. */
+    score_remove_notes (scherzo->score);
+    score_remove_chords (scherzo->score);
+
+    if (scherzo->pedal_pressed)
+       chord = &scherzo->notes_pedaled;
+    else
+       chord = &scherzo->notes_pressed;
+
+    _analyze_chord (chord, &signature, &root);
+
+    if (signature) {
+       /* Don't print root pitch for octaves and inversions,
+        * (since a pitch name alone looks like a major triad) */
+       if (signature->num_degrees < 3) {
+           chord_name = talloc_strdup (local, signature->name);
+       } else {
+           _spell_chord_by_signature (&scherzo->notes_pressed,
+                                      signature, *root);
+           _spell_chord_by_signature (&scherzo->notes_pedaled,
+                                      signature, *root);
+
+           chord_name = talloc_asprintf (local, "%s%s",
+                                         pitch_string (*root),
+                                         signature->name);
        }
+    } else if (chord->num_pitches > 2) {
+       chord_name = talloc_strdup (local, "?");
+    }
+
+    if (chord_name)
+       scherzo->chord = score_add_chord (scherzo->treble, chord_name);
+
+    for (i = 0; i < scherzo->notes_pressed.num_pitches; i++)
+    {
+       score_add_note (scherzo->score, scherzo->notes_pressed.pitches[i],
+                       SCORE_DURATION_WHOLE);
     }
 
-    if (found == 0) {
-       fprintf (stderr, "Internal error: Failed to find note to release.\n");
+    for (i = 0; i < scherzo->notes_pedaled.num_pitches; i++)
+    {
+       score_add_note (scherzo->score, scherzo->notes_pedaled.pitches[i],
+                       SCORE_DURATION_WHOLE);
     }
 
-    scherzo_analyze_chord (scherzo);
+    talloc_free (local);
 }
 
-static score_note_t *
+static void
+scherzo_release_note (scherzo_t *scherzo, pitch_t pitch)
+{
+    pitch_group_remove_pitch_enharmonic (&scherzo->notes_pressed, pitch);
+
+    if (scherzo->notes_pressed.num_pitches == 0)
+       scherzo_update_notes_and_chord (scherzo);
+}
+
+static pitch_t
 scherzo_press_note_midi (scherzo_t *scherzo, unsigned char midi_note)
 {
-    pitch_t pitch;
-    int octave;
+    pitch_t pitch = _midi_to_pitch (midi_note);
 
-    _midi_to_pitch_and_octave (midi_note, &pitch, &octave);
+    scherzo_press_note (scherzo, pitch);
 
-    return scherzo_press_note (scherzo, pitch, octave);
+    return pitch;
 }
 
 static void
 scherzo_release_note_midi (scherzo_t *scherzo, unsigned char midi_note)
 {
-    pitch_t pitch;
-    int octave;
-    _midi_to_pitch_and_octave (midi_note, &pitch, &octave);
-
-    scherzo_release_note (scherzo, pitch, octave);
+    scherzo_release_note (scherzo, _midi_to_pitch (midi_note));
 }
 
 static void
@@ -1161,56 +1197,44 @@ scherzo_press_pedal (scherzo_t *scherzo)
 {
     int i;
 
+    if (scherzo->pedal_pressed)
+       return;
+
     scherzo->pedal_pressed = 1;
 
     /* Copy all pressed notes to pedaled notes */
-    for (i = 0; i < scherzo->notes_pressed.num_notes; i++)
-       note_group_add_note (&scherzo->notes_pedaled, scherzo->notes_pressed.notes[i]);
+    for (i = 0; i < scherzo->notes_pressed.num_pitches; i++)
+       pitch_group_add_pitch (&scherzo->notes_pedaled, scherzo->notes_pressed.pitches[i]);
 }
 
 static void
 scherzo_release_pedal (scherzo_t *scherzo)
 {
-    score_note_t *note, *new_note;
     int i;
 
-    /* Make new notes in score for all pressed notes. */
-    for (i = 0; i < scherzo->notes_pressed.num_notes; i++) {
-       note = scherzo->notes_pressed.notes[i];
-       new_note = score_add_note (note->staff, note->pitch, note->octave, note->duration);
-       scherzo->notes_pressed.notes[i] = new_note;
-    }
+    if (! scherzo->pedal_pressed)
+       return;
 
-    /* Then remove all previously pedaled notes from the score. */
-    for (i = scherzo->notes_pedaled.num_notes - 1; i >=0; i--) {
-       note = scherzo->notes_pedaled.notes[i];
-       score_remove_note (note);
-       note_group_remove_note_at (&scherzo->notes_pedaled, i);
-    }
+    /* Remove all previously pedaled notes. */
+    for (i = scherzo->notes_pedaled.num_pitches - 1; i >=0; i--)
+       pitch_group_remove_pitch_at (&scherzo->notes_pedaled, i);
 
     scherzo->pedal_pressed = 0;
 
-    scherzo_analyze_chord (scherzo);
-
-    gtk_widget_queue_draw (scherzo->window);
+    scherzo_update_notes_and_chord (scherzo);
 }
 
-void
+static void
 _select_challenge (scherzo_t *scherzo)
 {
     category_t *category_unused;
     bool_t introduced_unused;
     item_t *item;
     challenge_t *challenge = &scherzo->challenge;
-    pitch_t pitch;
+    pitch_name_t pitch_name;
     int octave;
     char *s;
 
-    if (challenge->note) {
-       score_remove_note (challenge->note);
-       challenge->note = NULL;
-    }
-
     mnemon_select_item (&scherzo->mnemon,
                        &challenge->bin,
                        &challenge->item_index,
@@ -1235,25 +1259,25 @@ _select_challenge (scherzo_t *scherzo)
 
     switch (*s) {
     case 'C':
-       pitch = PITCH_C;
+       pitch_name = PITCH_NAME_C;
        break;
     case 'D':
-       pitch = PITCH_D;
+       pitch_name = PITCH_NAME_D;
        break;
     case 'E':
-       pitch = PITCH_E;
+       pitch_name = PITCH_NAME_E;
        break;
     case 'F':
-       pitch = PITCH_F;
+       pitch_name = PITCH_NAME_F;
        break;
     case 'G':
-       pitch = PITCH_G;
+       pitch_name = PITCH_NAME_G;
        break;
     case 'A':
-       pitch = PITCH_A;
+       pitch_name = PITCH_NAME_A;
        break;
     case 'B':
-       pitch = PITCH_B;
+       pitch_name = PITCH_NAME_B;
        break;
     default:
        fprintf (stderr, "Malformed pitch name: %s (expected 'A' - 'G')\n", s);
@@ -1268,34 +1292,26 @@ _select_challenge (scherzo_t *scherzo)
 
     octave = *s - '0';
 
-    challenge->note = score_add_note (challenge->staff, pitch, octave,
-                                     SCORE_DURATION_WHOLE);
+    challenge->pitch = PITCH (pitch_name, PITCH_ACCIDENTAL_NATURAL, octave);
+
+    challenge->active = 1;
     challenge->satisfied = 0;
     challenge->mistaken = 0;
 }
 
 /* Determine whether the user hit the correct note. */
 static void
-_judge_note (scherzo_t *scherzo, score_note_t *note)
+_judge_pitch (scherzo_t *scherzo, pitch_t pitch)
 {
     challenge_t *challenge = &scherzo->challenge;
 
-    if (! scherzo->challenge.note) {
-       score_set_note_color_rgb (note, 0.0, 0.0, 0.0); /* black */
+    if (! challenge->active)
        return;
-    }
 
-    if (note->pitch == challenge->note->pitch &&
-       note->octave == challenge->note->octave)
-    {
+    if (pitch == challenge->pitch)
        challenge->satisfied = 1;
-       score_set_note_color_rgb (note, 18/256., 130/256., 28/256.); /* green */
-    }
     else
-    {
        challenge->mistaken = 1;
-       score_set_note_color_rgb (note, 184/256., 4/256., 22/256.); /* red */
-    }
 }
 
 /* If the user got the right note (eventually), then score it in
@@ -1305,7 +1321,7 @@ _score_challenge (scherzo_t *scherzo)
 {
     challenge_t *challenge = &scherzo->challenge;
 
-    if (! challenge->note)
+    if (! challenge->active)
        return;
 
     if (! challenge->satisfied)
@@ -1326,7 +1342,7 @@ on_midi_input (unused (GIOChannel *channel),
     scherzo_t *scherzo = user_data;
     ssize_t remaining;
     snd_seq_event_t event;
-    score_note_t *note;
+    pitch_t pitch;
     int need_redraw = FALSE;
 
     remaining = read (scherzo->midi_fd, buf, MIDI_BUF_SIZE);
@@ -1346,8 +1362,8 @@ on_midi_input (unused (GIOChannel *channel),
            /* Incomplete event. Nothing to do. */
            break;
        case SND_SEQ_EVENT_NOTEON:
-           note = scherzo_press_note_midi (scherzo, event.data.note.note);
-           _judge_note (scherzo, note);
+           pitch = scherzo_press_note_midi (scherzo, event.data.note.note);
+           _judge_pitch (scherzo, pitch);
            need_redraw = TRUE;
            break;
        case SND_SEQ_EVENT_NOTEOFF:
@@ -1411,20 +1427,22 @@ main (int argc, char *argv[])
 
     scherzo.chord = NULL;
 
-    /* Default to octave 4 and natural for computer keyboard keypresses. */
+    /* Default to octave 4 for computer keyboard keypresses. */
     scherzo.keyboard_octave = 4;
-    scherzo.keyboard_accidental = PITCH_ACCIDENTAL_NATURAL;
 
-    note_group_init (scherzo.ctx, &scherzo.notes_pressed);
-    note_group_init (scherzo.ctx, &scherzo.notes_pedaled);
+    pitch_group_init (scherzo.ctx, &scherzo.notes_pressed);
+    pitch_group_init (scherzo.ctx, &scherzo.notes_pedaled);
 
     scherzo.pedal_pressed = 0;
 
+    scherzo.key = PITCH_CLASS_LITERAL (C, NATURAL);
+    score_set_key (scherzo.score, scherzo.key);
+
     mnemon_init (&scherzo.mnemon);
     /* XXX: Should create a default file if one cannot be loaded. */
     mnemon_load_category (&scherzo.mnemon, "scherzo-notes");
 
-    scherzo.challenge.note = NULL;
+    scherzo.challenge.active = 0;
 /*
     _select_challenge (&scherzo);
 */