Add correct sizing/spacing of staves and braces for ledger lines.

[scherzo] / score.c

diff --git a/score.c b/score.c
index 0c9d5f37cb37e20d9913e0601ef4b66246ccf777..6530a503c7731fe43508dacf0b2fc2d9db543628 100644 (file)
--- a/score.c
+++ b/score.c
@@ -28,6 +28,13 @@ struct score_staff
 
     score_note_t **notes;
     int num_notes;
+
+    /* How many ledger lines are needed for current notes */
+    int upper_ledger_lines;
+    int lower_ledger_lines;
+
+    /* Y position of top full line of staff */
+    int y_pos;
 };
 
 typedef struct score_brace
@@ -38,7 +45,7 @@ typedef struct score_brace
 
 struct score
 {
-    /* Height of a single staff */
+    /* Nominal height of a single staff (ledger lines may make it larger) */
     int staff_height;
 
     /* Height of one space within a staff */
@@ -108,9 +115,16 @@ _draw_brace (score_t *score, cairo_t *cr,
 {
     cairo_glyph_t brace_glyph;
     cairo_text_extents_t brace_extents;
+    double top, bottom;
+
+    if (brace->num_staves == 0)
+       return;
 
     cairo_save (cr);
 
+    top = score->staves[brace->first_staff]->y_pos;
+    bottom = score->staves[brace->first_staff + brace->num_staves - 1]->y_pos + score->staff_height;
+
     cairo_select_font_face (cr, "Gonville-Brace", 0, 0);
 
     /* XXX: This hard-coded glyph index is pretty ugly. We should
@@ -120,13 +134,13 @@ _draw_brace (score_t *score, cairo_t *cr,
      * than just the bare index here). */
     brace_glyph.index = 300;
     brace_glyph.x = 0;
-    brace_glyph.y = score->staff_height * (brace->first_staff + (2 * brace->num_staves - 1) / 2.0) + 1;
+    brace_glyph.y = top + (bottom - top) / 2.0 + score->line_width / 2.0;
 
     /* XXX: This font size (in conjunction with the glyph selection)
      * is a rough guess at best. We should figure out how the brace
      * font is intended to be used and actually measure to find the
      * correctly-sized glyph. */
-    cairo_set_font_size (cr, (score->staff_height * 3) / 3.85);
+    cairo_set_font_size (cr, (bottom - top) / 3.85);
 
     cairo_glyph_extents (cr, &brace_glyph, 1, &brace_extents);
 
@@ -170,6 +184,15 @@ _draw_note (score_t *score, cairo_t *cr,
 {
     double line;
     cairo_glyph_t note_glyph;
+    static double extend_factor = 0.25;
+
+    void _draw_ledger_line (double line, double width) {
+       cairo_move_to (cr,
+                      - width * extend_factor / 2.0,
+                      score->space_height * line + score->line_width / 2.0);
+       cairo_rel_line_to (cr, (1 + extend_factor) * width, 0);
+       cairo_stroke (cr);
+    }
 
     cairo_save (cr);
 
@@ -203,7 +226,22 @@ _draw_note (score_t *score, cairo_t *cr,
     }
 
     note_glyph.x = 0;
-    note_glyph.y = score->space_height * line + score->line_width / 2.0;
+    note_glyph.y = score->space_height * line;
+
+    if (line < 0 || line > 4) {
+       int i;
+       cairo_text_extents_t note_extents;
+
+       cairo_glyph_extents (cr, &note_glyph, 1, &note_extents);
+
+       if (line < 0) {
+           for (i = -1; i >= line; i--)
+               _draw_ledger_line (i, note_extents.width);
+       } else {
+           for (i = 5; i <= line; i++)
+               _draw_ledger_line (i, note_extents.width);
+       }
+    }
 
     cairo_set_source_rgb (cr, 0.0, 0.0, 0.0); /* black */
     cairo_show_glyphs (cr, &note_glyph, 1);
@@ -220,6 +258,8 @@ _draw_staff (score_t *score, cairo_t *cr,
 
     cairo_save (cr);
 
+    cairo_translate (cr, 0, staff->y_pos);
+
     cairo_select_font_face (cr, "Gonville-26", 0, 0);
 
     cairo_set_font_size (cr, score->staff_height);
@@ -238,7 +278,7 @@ _draw_staff (score_t *score, cairo_t *cr,
        break;
     }
     clef_glyph.x = 3 * score->line_width;
-    clef_glyph.y += 1;
+    clef_glyph.y += score->line_width / 2.0;
 
     cairo_set_source_rgb (cr, 0.0, 0.0, 0.0); /* black */
     cairo_show_glyphs (cr, &clef_glyph, 1);
@@ -273,9 +313,25 @@ score_draw (score_t *score, cairo_t *cr)
 {
     int i;
     int staff_width = score->width;
+    int staff_y_pos;
+
+    if (score->num_staves == 0)
+       return;
 
     cairo_save (cr);
 
+    /* Before drawing anything, position each staff based on the size
+     * of each (including ledger lines) */
+    staff_y_pos = 0;
+    for (i = 0; i < score->num_staves; i++) {
+       score_staff_t *staff = score->staves[i];
+       staff_y_pos += staff->upper_ledger_lines * score->space_height;
+       staff->y_pos = staff_y_pos;
+       staff_y_pos += (score->staff_height +
+                       staff->lower_ledger_lines * score->space_height +
+                       score->staff_height);
+    }
+
     if (score->num_braces)
     {
        int brace_width;
@@ -295,16 +351,16 @@ score_draw (score_t *score, cairo_t *cr)
     /* Vertical lines at each end */
     cairo_rectangle (cr,
                     score->line_width / 2.0,
-                    score->line_width / 2.0,
+                    score->staves[0]->y_pos + score->line_width / 2.0,
                     staff_width - score->line_width,
-                    score->staff_height * 3);
+                    score->staves[score->num_staves-1]->y_pos + score->staff_height - score->staves[0]->y_pos);
     cairo_set_source_rgb (cr, 0.0, 0.0, 0.0); /* black */
     cairo_set_line_width (cr, score->line_width);
     cairo_stroke (cr);
 
     for (i = 0; i < score->num_staves; i++) {
-       _draw_staff (score, cr, score->staves[i], staff_width);
-       cairo_translate (cr, 0, 2 * score->staff_height);
+       score_staff_t *staff = score->staves[i];
+       _draw_staff (score, cr, staff, staff_width);
     }
 
     cairo_restore (cr);
@@ -350,6 +406,9 @@ score_add_staff (score_t *score, score_clef_t clef)
     staff->notes = NULL;
     staff->num_notes = 0;
 
+    staff->upper_ledger_lines = 0;
+    staff->lower_ledger_lines = 0;
+
     score->num_staves++;
     score->staves = talloc_realloc (score,
                                    score->staves,
@@ -372,6 +431,7 @@ score_add_note (score_staff_t *staff,
                score_duration_t duration)
 {
     score_note_t *note;
+    double line;
 
     note = talloc (staff, score_note_t);
     if (note == NULL)
@@ -382,6 +442,17 @@ score_add_note (score_staff_t *staff,
     note->octave = octave;
     note->duration = duration;
 
+    line = _score_note_to_line (staff, note);
+    if (line < 0) {
+       int lines = (int) (- line);
+       if (lines > staff->upper_ledger_lines)
+           staff->upper_ledger_lines = lines;
+    } else {
+       int lines = (int) (line - 4);
+       if (lines > staff->lower_ledger_lines)
+           staff->lower_ledger_lines = lines;
+    }
+
     staff->num_notes++;
     staff->notes = talloc_realloc (staff,
                                   staff->notes,