]> git.cworth.org Git - scherzo/blobdiff - scherzo.c
Allow computer-keyboard input of accidentals, and draw accidentals.
[scherzo] / scherzo.c
index 955f5b7551d773f865feabb1761424515a49a233..b9a463368b86129dd1eee0cdd74cdabcecf7b561 100644 (file)
--- a/scherzo.c
+++ b/scherzo.c
@@ -24,6 +24,8 @@
 #include "score.h"
 #include "mnemon.h"
 
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+
 #define unused(foo) foo __attribute__((unused))
 
 #define MIDI_BUF_SIZE 4096
@@ -39,6 +41,14 @@ typedef struct challenge
     int mistaken;
 } challenge_t;
 
+typedef struct note_group
+{
+    void *ctx;
+    score_note_t **notes;
+    int size;
+    int num_notes;
+} note_group_t;
+
 typedef struct scherzo
 {
     void *ctx;
@@ -48,16 +58,45 @@ typedef struct scherzo
     int staff_height;
     score_staff_t *treble;
     score_staff_t *bass;
+    score_chord_t *chord;
+
+    /* The word "keyboard" here is referring to a "computer
+     * keyboard". Any "piano keyboard" key knows its own octave and
+     * accidental already. */
+    int keyboard_octave;
+    score_pitch_accidental_t keyboard_accidental;
+
     int midi_fd;
     snd_midi_event_t *snd_midi_event;
 
     mnemon_t mnemon;
     challenge_t challenge;
 
-    int num_notes_pressed;
-    score_note_t **notes_pressed;
+    note_group_t notes_pressed;
+    note_group_t notes_pedaled;
+
+    int pedal_pressed;
 } scherzo_t;
 
+/* Forward declarations. */
+static score_note_t *
+scherzo_press_note (scherzo_t *scherzo, score_pitch_t pitch, int octave);
+
+static void
+scherzo_release_note (scherzo_t *scherzo, score_pitch_t pitch, int octave);
+
+static void
+scherzo_press_pedal (scherzo_t *scherzo);
+
+static void
+scherzo_release_pedal (scherzo_t *scherzo);
+
+static void
+_judge_note (scherzo_t *scherzo, score_note_t *note);
+
+static void
+_score_challenge (scherzo_t *scherzo);
+
 static int
 on_delete_event_quit (unused (GtkWidget *widget),
                      unused (GdkEvent *event),
@@ -92,7 +131,7 @@ on_expose_event_draw (GtkWidget *widget,
     cairo_paint (cr);
 
     /* Add some padding on the sides and top */
-    cairo_translate (cr, pad, 2 * scherzo->staff_height);
+    cairo_translate (cr, pad, scherzo->staff_height);
     score_set_staff_height (score, scherzo->staff_height);
     score_set_width (score, widget_width - 2 * pad);
 
@@ -107,6 +146,14 @@ on_key_press_event (GtkWidget *widget,
                    void *user_data)
 {
     scherzo_t *scherzo = user_data;
+    int octave;
+    score_pitch_name_t pitch_name;
+    score_pitch_t pitch;
+
+    if (scherzo->challenge.note)
+       octave = scherzo->challenge.note->octave;
+    else
+       octave = scherzo->keyboard_octave;
 
     switch (key->keyval) {
     case GDK_KEY_plus:
@@ -128,12 +175,192 @@ on_key_press_event (GtkWidget *widget,
     case GDK_KEY_Escape:
        gtk_main_quit ();
        return FALSE;
+    case GDK_KEY_c:
+    case GDK_KEY_C:
+       pitch_name = SCORE_PITCH_NAME_C;
+       break;
+    case GDK_KEY_d:
+    case GDK_KEY_D:
+       pitch_name = SCORE_PITCH_NAME_D;
+       break;
+    case GDK_KEY_e:
+    case GDK_KEY_E:
+       pitch_name = SCORE_PITCH_NAME_E;
+       break;
+    case GDK_KEY_f:
+    case GDK_KEY_F:
+       pitch_name = SCORE_PITCH_NAME_F;
+       break;
+    case GDK_KEY_g:
+    case GDK_KEY_G:
+       pitch_name = SCORE_PITCH_NAME_G;
+       break;
+    case GDK_KEY_a:
+    case GDK_KEY_A:
+       pitch_name = SCORE_PITCH_NAME_A;
+       break;
+    case GDK_KEY_b:
+    case GDK_KEY_B:
+       pitch_name = SCORE_PITCH_NAME_B;
+       break;
+    case GDK_KEY_0:
+    case GDK_KEY_1:
+    case GDK_KEY_2:
+    case GDK_KEY_3:
+    case GDK_KEY_4:
+    case GDK_KEY_5:
+    case GDK_KEY_6:
+    case GDK_KEY_7:
+    case GDK_KEY_8:
+       scherzo->keyboard_octave = key->keyval - GDK_KEY_0;
+       break;
+    case GDK_KEY_space:
+       scherzo_press_pedal (scherzo);
+       break;
+    case GDK_KEY_Up:
+       if (scherzo->keyboard_accidental < SCORE_PITCH_ACCIDENTAL_DOUBLE_SHARP)
+           scherzo->keyboard_accidental++;
+       break;
+    case GDK_KEY_Down:
+       if (scherzo->keyboard_accidental > SCORE_PITCH_ACCIDENTAL_DOUBLE_FLAT)
+           scherzo->keyboard_accidental--;
+       break;
+    }
+
+    pitch = SCORE_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))
+    {
+       score_note_t *note;
+
+       note = scherzo_press_note (scherzo, pitch, octave);
+       _judge_note (scherzo, note);
+       gtk_widget_queue_draw (scherzo->window);
+
+       return TRUE;
     }
 
-    /* Allow the event to propagate to other handlers. */
+
+    /* Allow an unhandled event to propagate to other handlers. */
     return FALSE;
 }
 
+static int
+on_key_release_event (unused (GtkWidget *widget),
+                     GdkEventKey *key,
+                     void *user_data)
+{
+    scherzo_t *scherzo = user_data;
+    int octave;
+    score_pitch_name_t pitch_name;
+    score_pitch_t pitch;
+
+    if (scherzo->challenge.note)
+       octave = scherzo->challenge.note->octave;
+    else
+       octave = scherzo->keyboard_octave;
+
+    switch (key->keyval) {
+    case GDK_KEY_c:
+    case GDK_KEY_C:
+       pitch_name = SCORE_PITCH_NAME_C;
+       break;
+    case GDK_KEY_d:
+    case GDK_KEY_D:
+       pitch_name = SCORE_PITCH_NAME_D;
+       break;
+    case GDK_KEY_e:
+    case GDK_KEY_E:
+       pitch_name = SCORE_PITCH_NAME_E;
+       break;
+    case GDK_KEY_f:
+    case GDK_KEY_F:
+       pitch_name = SCORE_PITCH_NAME_F;
+       break;
+    case GDK_KEY_g:
+    case GDK_KEY_G:
+       pitch_name = SCORE_PITCH_NAME_G;
+       break;
+    case GDK_KEY_a:
+    case GDK_KEY_A:
+       pitch_name = SCORE_PITCH_NAME_A;
+       break;
+    case GDK_KEY_b:
+    case GDK_KEY_B:
+       pitch_name = SCORE_PITCH_NAME_B;
+       break;
+    case GDK_KEY_space:
+       scherzo_release_pedal (scherzo);
+       break;
+    }
+
+    pitch = SCORE_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))
+    {
+       scherzo_release_note (scherzo, pitch, octave);
+       _score_challenge (scherzo);
+       gtk_widget_queue_draw (scherzo->window);
+
+       return TRUE;
+    }
+
+
+    /* Allow an unhandled event to propagate to other handlers. */
+    return FALSE;
+}
+
+static unsigned char
+_score_pitch_and_octave_to_midi (score_pitch_t pitch,
+                                int octave)
+{
+    unsigned char midi_note = 12 * (octave + 1);
+
+    switch (SCORE_PITCH_NAME (pitch)) {
+    case SCORE_PITCH_NAME_C:
+       break;
+    case SCORE_PITCH_NAME_D:
+       midi_note += 2;
+       break;
+    case SCORE_PITCH_NAME_E:
+       midi_note += 4;
+       break;
+    case SCORE_PITCH_NAME_F:
+       midi_note += 5;
+       break;
+    case SCORE_PITCH_NAME_G:
+       midi_note += 7;
+       break;
+    case SCORE_PITCH_NAME_A:
+       midi_note += 9;
+       break;
+    case SCORE_PITCH_NAME_B:
+       midi_note += 11;
+       break;
+    }
+
+    switch (SCORE_PITCH_ACCIDENTAL (pitch)) {
+    case SCORE_PITCH_ACCIDENTAL_DOUBLE_FLAT:
+       midi_note -= 2;
+       break;
+    case SCORE_PITCH_ACCIDENTAL_FLAT:
+       midi_note -= 1;
+       break;
+    case SCORE_PITCH_ACCIDENTAL_NATURAL:
+       break;
+    case SCORE_PITCH_ACCIDENTAL_SHARP:
+       midi_note += 1;
+       break;
+    case SCORE_PITCH_ACCIDENTAL_DOUBLE_SHARP:
+       midi_note += 2;
+       break;
+    }
+
+    return midi_note;
+}
+
 static void
 _midi_to_score_pitch_and_octave (unsigned char midi_note,
                                 score_pitch_t *pitch,
@@ -182,58 +409,378 @@ _midi_to_score_pitch_and_octave (unsigned char midi_note,
     }
 }
 
+/* Determine a chord name (if any) from the current notes pressed */
+
+typedef struct analyzed_note {
+    /* Original note being analzyed. */
+    score_note_t *note;
+
+    /* Absolute pitch (expressed as midi number). */
+    int midi_pitch;
+
+    /* Pitch relative to bass note. */
+    int relative_pitch;
+} analyzed_note_t;
+
+static int
+_compare_analyzed_note_by_midi_pitch (const void *va, const void *vb)
+{
+    const analyzed_note_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)
+{
+    const analyzed_note_t *a = va, *b = vb;
+
+    return a->relative_pitch - b->relative_pitch;
+}
+
+static int
+_chord_signature_matches (analyzed_note_t *notes,
+                         int num_notes,
+                         int *signature_pitches,
+                         int num_signature_pitches)
+{
+    int i;
+
+    if (num_notes != num_signature_pitches)
+           return 0;
+
+    for (i = 0; i < num_notes; i++)
+       if (notes[i].relative_pitch != signature_pitches[i])
+           return 0;
+
+    return 1;
+}
+
+static void
+scherzo_analyze_chord (scherzo_t *scherzo)
+{
+    void *local = talloc_new (NULL);
+    analyzed_note_t *notes;
+    note_group_t *note_group;
+    unsigned i, j, num_notes;
+    int bass_pitch;
+    const char *chord_name = NULL;
+
+    if (scherzo->pedal_pressed)
+       note_group = &scherzo->notes_pedaled;
+    else
+       note_group = &scherzo->notes_pressed;
+
+    num_notes = note_group->num_notes;
+
+    struct { int pitches[1]; const char *name; } octaves[] = {
+       { {0}, "Octave"}
+    };
+
+    struct { int pitches[2]; const char *name; } intervals[] = {
+       { {0, 1}, "Minor 2nd"},
+       { {0, 2}, "Major 2nd"},
+       { {0, 3}, "Minor 3rd"},
+       { {0, 4}, "Major 3rd"},
+       { {0, 5}, "Perfect 4th"},
+       { {0, 6}, "Diminished 5th/Augmented 4th"},
+       { {0, 7}, "Perfect 5th"},
+       { {0, 8}, "Minor 6th"},
+       { {0, 9}, "Major 6th"},
+       { {0, 10}, "Minor 7th"},
+       { {0, 11}, "Major 7th"}
+    };
+
+    struct { int pitches[3]; const char *name; } triads[] = {
+       { {0, 4, 8}, "Augmented triad" },
+       { {0, 4, 7}, "Major triad" },
+       { {0, 3, 7}, "Minor triad" },
+       { {0, 3, 6}, "Diminished triad" }
+    };
+
+    struct { int pitches[4]; const char *name; } sevenths[] = {
+       { {0, 4, 8, 11}, "Augmented/major 7" },
+       { {0, 4, 8, 10}, "Augmented 7" },
+       { {0, 4, 7, 11}, "Major 7" },
+       { {0, 4, 7, 10}, "Dominant 7" },
+       { {0, 3, 7, 11}, "Minor/major 7" },
+       { {0, 3, 7, 10}, "Minor 7" },
+       { {0, 3, 6, 11}, "Diminished/major 7" },
+       { {0, 3, 6, 10}, "Half-diminished 7" },
+       { {0, 3, 6, 9},  "Diminished 7" }
+    };
+
+    if (scherzo->chord) {
+       score_remove_chord (scherzo->chord);
+       scherzo->chord = NULL;
+    }
+
+    if (num_notes <= 1)
+       goto DONE;
+
+    notes = talloc_array (local, analyzed_note_t, num_notes);
+    if (notes == 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 = _score_pitch_and_octave_to_midi (note->pitch,
+                                                              note->octave);
+       /* Relative pitch will be filled in after sorting. */
+       notes[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);
+    
+    bass_pitch = notes[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;
+    }
+
+    /* Now, sort again by relative pitch. */
+    qsort (notes, num_notes, sizeof (analyzed_note_t),
+          _compare_analyzed_note_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) {
+                   j = i+1;
+                   while (j < num_notes &&
+                          notes[j].relative_pitch == notes[i].relative_pitch)
+                   {
+                           j++;
+                   }
+                   /* The loop incremented j one past the last
+                    * duplicate. Decrement so that it points to the
+                    * last duplicate (and is guaranteed to not exceed
+                    * the array bounds).*/
+                   j--;
+
+                   if (j < num_notes - 1) {
+                           memmove (&notes[i+1], &notes[j+1],
+                                    (num_notes - j) * sizeof (analyzed_note_t));
+                   }
+
+                   num_notes -= (j - i);
+           }
+    }
+
+    switch (num_notes) {
+    case 1:
+       for (i = 0; i < ARRAY_SIZE (octaves); i++) {
+           if (_chord_signature_matches (notes, num_notes, octaves[i].pitches, 1))
+               chord_name = octaves[i].name;
+       }
+       break;
+    case 2:
+       for (i = 0; i < ARRAY_SIZE (intervals); i++) {
+           if (_chord_signature_matches (notes, num_notes, intervals[i].pitches, 2))
+               chord_name = intervals[i].name;
+       }
+       break;
+    case 3:
+       for (i = 0; i < ARRAY_SIZE (triads); i++) {
+           if (_chord_signature_matches (notes, num_notes, triads[i].pitches, 3))
+               chord_name = triads[i].name;
+       }
+       break;
+    case 4:
+       for (i = 0; i < ARRAY_SIZE(sevenths); i++) {
+           if (_chord_signature_matches (notes, num_notes, sevenths[i].pitches, 4))
+               chord_name = sevenths[i].name;
+       }
+       break;
+    }
+
+    if (chord_name)
+       scherzo->chord = score_add_chord (scherzo->treble, chord_name);
+    else
+       scherzo->chord = score_add_chord (scherzo->treble, "Unknown or not a chord");
+
+DONE:
+    talloc_free (local);
+}
+
+static void
+note_group_init (void *ctx, note_group_t *group)
+{
+    group->ctx = ctx;
+    group->notes = NULL;
+    group->size = 0;
+    group->num_notes = 0;
+}
+
+static void
+note_group_add_note (note_group_t *group, score_note_t *note)
+{
+    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)
+       {
+           return;
+       }
+    }
+
+    group->num_notes++;
+
+    if (group->num_notes > group->size) {
+       group->size++;
+       group->notes = talloc_realloc (group->ctx, group->notes,
+                                      score_note_t*, group->size);
+
+       if (group->notes == NULL) {
+           fprintf (stderr, "Out of memory.\n");
+           exit (1);
+       }
+    }
+
+    group->notes[group->num_notes - 1] = note;
+}
+
+static void
+note_group_remove_note_at (note_group_t *group, int i)
+{
+    if (i >= group->num_notes) {
+       fprintf (stderr, "Internal error: No note to remove at index %d\n", i);
+       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*));
+    }
+    group->num_notes--;
+}
+
 static score_note_t *
-scherzo_add_note_midi (scherzo_t *scherzo, unsigned char midi_note)
+scherzo_press_note (scherzo_t *scherzo, score_pitch_t pitch, int octave)
 {
     score_staff_t *staff;
-    score_pitch_t pitch;
-    int octave;
     score_note_t *note;
+    int i;
 
-    staff = scherzo->challenge.staff;
+    if (scherzo->challenge.note) {
+       staff = scherzo->challenge.staff;
+    } else if (octave >= 4) {
+       staff = scherzo->treble;
+    } else {
+       staff = scherzo->bass;
+    }
 
-    _midi_to_score_pitch_and_octave (midi_note, &pitch, &octave);
+    /* 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];
+       }
+    }
 
     note = score_add_note (staff, pitch, octave, SCORE_DURATION_WHOLE);
 
-    scherzo->num_notes_pressed++;
-    scherzo->notes_pressed = talloc_realloc (scherzo->ctx,
-                                            scherzo->notes_pressed,
-                                            score_note_t*,
-                                            scherzo->num_notes_pressed);
-    if (scherzo->notes_pressed == NULL) {
-       fprintf (stderr, "Out of memory.\n");
-       exit (1);
-    }
+    note_group_add_note (&scherzo->notes_pressed, note);
 
-    scherzo->notes_pressed[scherzo->num_notes_pressed - 1] = note;
+    if (scherzo->pedal_pressed)
+       note_group_add_note (&scherzo->notes_pedaled, note);
+
+    scherzo_analyze_chord (scherzo);
 
     return note;
 }
 
 static void
-scherzo_remove_note_midi (scherzo_t *scherzo, unsigned char midi_note)
+scherzo_release_note (scherzo_t *scherzo, score_pitch_t pitch, int octave)
 {
-    score_pitch_t pitch;
-    int octave;
     score_note_t *note;
     int i;
+    int found = 0;
 
-    _midi_to_score_pitch_and_octave (midi_note, &pitch, &octave);
-
-    for (i = 0; i < scherzo->num_notes_pressed; i++) {
-       note = scherzo->notes_pressed[i];
+    for (i = scherzo->notes_pressed.num_notes - 1; i >=0; i--) {
+       note = scherzo->notes_pressed.notes[i];
        if (note->pitch == pitch && note->octave == octave) {
-           score_remove_note (note);
-           if (i < scherzo->num_notes_pressed - 1) {
-               memmove (scherzo->notes_pressed + i,
-                        scherzo->notes_pressed + i + 1,
-                        (scherzo->num_notes_pressed - 1 - i) * sizeof (score_note_t*));
-           }
-           scherzo->num_notes_pressed--;
-           i--;
+           found = 1;
+           if (! scherzo->pedal_pressed)
+               score_remove_note (note);
+           note_group_remove_note_at (&scherzo->notes_pressed, i);
        }
     }
+
+    if (found == 0) {
+       fprintf (stderr, "Internal error: Failed to find note to release.\n");
+    }
+
+    scherzo_analyze_chord (scherzo);
+}
+
+static score_note_t *
+scherzo_press_note_midi (scherzo_t *scherzo, unsigned char midi_note)
+{
+    score_pitch_t pitch;
+    int octave;
+
+    _midi_to_score_pitch_and_octave (midi_note, &pitch, &octave);
+
+    return scherzo_press_note (scherzo, pitch, octave);
+}
+
+static void
+scherzo_release_note_midi (scherzo_t *scherzo, unsigned char midi_note)
+{
+    score_pitch_t pitch;
+    int octave;
+    _midi_to_score_pitch_and_octave (midi_note, &pitch, &octave);
+
+    scherzo_release_note (scherzo, pitch, octave);
+}
+
+static void
+scherzo_press_pedal (scherzo_t *scherzo)
+{
+    int i;
+
+    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]);
+}
+
+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;
+    }
+
+    /* 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);
+    }
+
+    scherzo->pedal_pressed = 0;
+
+    scherzo_analyze_chord (scherzo);
+
+    gtk_widget_queue_draw (scherzo->window);
 }
 
 void
@@ -276,25 +823,25 @@ _select_challenge (scherzo_t *scherzo)
 
     switch (*s) {
     case 'C':
-       pitch = SCORE_PITCH_VALUE(C, NATURAL);
+       pitch = SCORE_PITCH_C;
        break;
     case 'D':
-       pitch = SCORE_PITCH_VALUE(D, NATURAL);
+       pitch = SCORE_PITCH_D;
        break;
     case 'E':
-       pitch = SCORE_PITCH_VALUE(E, NATURAL);
+       pitch = SCORE_PITCH_E;
        break;
     case 'F':
-       pitch = SCORE_PITCH_VALUE(F, NATURAL);
+       pitch = SCORE_PITCH_F;
        break;
     case 'G':
-       pitch = SCORE_PITCH_VALUE(G, NATURAL);
+       pitch = SCORE_PITCH_G;
        break;
     case 'A':
-       pitch = SCORE_PITCH_VALUE(A, NATURAL);
+       pitch = SCORE_PITCH_A;
        break;
     case 'B':
-       pitch = SCORE_PITCH_VALUE(B, NATURAL);
+       pitch = SCORE_PITCH_B;
        break;
     default:
        fprintf (stderr, "Malformed pitch name: %s (expected 'A' - 'G')\n", s);
@@ -321,14 +868,21 @@ _judge_note (scherzo_t *scherzo, score_note_t *note)
 {
     challenge_t *challenge = &scherzo->challenge;
 
+    if (! scherzo->challenge.note) {
+       score_set_note_color_rgb (note, 0.0, 0.0, 0.0); /* black */
+       return;
+    }
+
     if (note->pitch == challenge->note->pitch &&
        note->octave == challenge->note->octave)
     {
        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 */
     }
 }
 
@@ -339,6 +893,9 @@ _score_challenge (scherzo_t *scherzo)
 {
     challenge_t *challenge = &scherzo->challenge;
 
+    if (! challenge->note)
+       return;
+
     if (! challenge->satisfied)
        return;
 
@@ -358,6 +915,7 @@ on_midi_input (unused (GIOChannel *channel),
     ssize_t remaining;
     snd_seq_event_t event;
     score_note_t *note;
+    int need_redraw = FALSE;
 
     remaining = read (scherzo->midi_fd, buf, MIDI_BUF_SIZE);
 
@@ -369,20 +927,21 @@ on_midi_input (unused (GIOChannel *channel),
                                          next, remaining, &event);
 
        remaining -= consumed;
+       next += consumed;
 
        switch (event.type) {
        case SND_SEQ_EVENT_NONE:
            /* Incomplete event. Nothing to do. */
            break;
        case SND_SEQ_EVENT_NOTEON:
-           note = scherzo_add_note_midi (scherzo, event.data.note.note);
+           note = scherzo_press_note_midi (scherzo, event.data.note.note);
            _judge_note (scherzo, note);
-           gtk_widget_queue_draw (scherzo->window);
+           need_redraw = TRUE;
            break;
        case SND_SEQ_EVENT_NOTEOFF:
-           scherzo_remove_note_midi (scherzo, event.data.note.note);
+           scherzo_release_note_midi (scherzo, event.data.note.note);
            _score_challenge (scherzo);
-           gtk_widget_queue_draw (scherzo->window);
+           need_redraw = TRUE;
            break;
        case SND_SEQ_EVENT_CLOCK:
            /* Ignore for now as my piano sends a constant stream of these. */
@@ -390,13 +949,29 @@ on_midi_input (unused (GIOChannel *channel),
        case SND_SEQ_EVENT_SENSING:
            /* Ignore for now as my piano sends a constant stream of these. */
            break;
+       case SND_SEQ_EVENT_CONTROLLER:
+           /* XXX: My piano gives me 64 for the sustain pedal, is
+            * that universal? */
+           if (event.data.control.param == 64) {
+               if (event.data.control.value == 0)
+                   scherzo_release_pedal (scherzo);
+               else
+                   scherzo_press_pedal (scherzo);
+           } else {
+               fprintf (stderr, "Fixme: Unhandled MIDI Control event (param=%d, value=%d)\n",
+                        event.data.control.param, event.data.control.value);
+           }
+           break;
        default:
            fprintf (stderr, "Fixme: Do not yet know how to handle MIDI event %d\n",
                     event.type);
            break;
        }
     }
-    
+
+    if (need_redraw)
+       gtk_widget_queue_draw (scherzo->window);
+
     /* Return TRUE to continue to get called in the future. */
     return TRUE;
 }
@@ -415,22 +990,32 @@ main (int argc, char *argv[])
     scherzo.ctx = talloc_new (NULL);
 
     scherzo.score = score_create (scherzo.ctx);
-    scherzo.staff_height = 48;
+    scherzo.staff_height = 100;
     score_set_staff_height (scherzo.score, scherzo.staff_height);
 
     score_add_brace (scherzo.score, 2);
     scherzo.treble = score_add_staff (scherzo.score, SCORE_CLEF_G);
     scherzo.bass = score_add_staff (scherzo.score, SCORE_CLEF_F);
 
-    scherzo.num_notes_pressed = 0;
-    scherzo.notes_pressed = NULL;
+    scherzo.chord = NULL;
+
+    /* Default to octave 4 and natural for computer keyboard keypresses. */
+    scherzo.keyboard_octave = 4;
+    scherzo.keyboard_accidental = SCORE_PITCH_ACCIDENTAL_NATURAL;
+
+    note_group_init (scherzo.ctx, &scherzo.notes_pressed);
+    note_group_init (scherzo.ctx, &scherzo.notes_pedaled);
+
+    scherzo.pedal_pressed = 0;
 
     mnemon_init (&scherzo.mnemon);
     /* XXX: Should create a default file if one cannot be loaded. */
-    mnemon_load_category (&scherzo.mnemon, "scherzo");
+    mnemon_load_category (&scherzo.mnemon, "scherzo-notes");
 
     scherzo.challenge.note = NULL;
+/*
     _select_challenge (&scherzo);
+*/
 
     err = snd_midi_event_new (MIDI_BUF_SIZE, &scherzo.snd_midi_event);
     if (err) {
@@ -452,7 +1037,7 @@ main (int argc, char *argv[])
 
     scherzo.window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
 
-    gtk_window_set_default_size (GTK_WINDOW (scherzo.window), 600, 400);
+    gtk_window_set_default_size (GTK_WINDOW (scherzo.window), 1000, 600);
 
     g_signal_connect (scherzo.window, "delete-event",
                      G_CALLBACK (on_delete_event_quit), NULL);
@@ -465,9 +1050,13 @@ main (int argc, char *argv[])
                      G_CALLBACK (on_expose_event_draw),
                      &scherzo);
 
-    g_signal_connect (scherzo.window, "key-press-event",  
+    g_signal_connect (scherzo.window, "key-press-event",
                      G_CALLBACK (on_key_press_event),
                      &scherzo);
+
+    g_signal_connect (scherzo.window, "key-release-event",
+                     G_CALLBACK (on_key_release_event),
+                     &scherzo);
     
     gtk_widget_show_all (scherzo.window);