source file of the GNU LilyPond music typesetter
- (c) 1997--2007 Han-Wen Nienhuys <hanwen@xs4all.nl>
+ (c) 1997--2009 Han-Wen Nienhuys <hanwen@xs4all.nl>
Jan Nieuwenhuizen <janneke@gnu.org>
*/
return Stencil (b, expr);
}
-Stencil
-Lookup::dashed_slur (Bezier b, Real thick, Real dash_period, Real dash_fraction)
-{
- SCM l = SCM_EOL;
-
- Real on = dash_fraction * dash_period;
- Real off = dash_period - on;
-
- for (int i = 4; i--;)
- l = scm_cons (ly_offset2scm (b.control_[i]), l);
-
- SCM at = (scm_list_n (ly_symbol2scm ("dashed-slur"),
- scm_from_double (thick),
- scm_from_double (on),
- scm_from_double (off),
- ly_quote_scm (l),
- SCM_UNDEFINED));
-
- Box box (b.extent (X_AXIS), b.extent (Y_AXIS));
- return Stencil (box, at);
-}
-
Stencil
Lookup::rotated_box (Real slope, Real width, Real thick, Real blot)
{
Make a smooth curve along the points
*/
Stencil
-Lookup::slur (Bezier curve, Real curvethick, Real linethick)
+Lookup::slur (Bezier curve, Real curvethick, Real linethick,
+ SCM dash_details)
{
+ Stencil return_value;
+
+ /*
+ calculate the offset for the two beziers that make the sandwich
+ for the slur
+ */
Real alpha = (curve.control_[3] - curve.control_[0]).arg ();
Bezier back = curve;
Offset perp = curvethick * complex_exp (Offset (0, alpha + M_PI / 2)) * 0.5;
- back.reverse ();
back.control_[1] += perp;
back.control_[2] += perp;
curve.control_[1] -= perp;
curve.control_[2] -= perp;
-
- SCM scontrols[8];
-
- for (int i = 0; i < 4; i++)
- scontrols[i] = ly_offset2scm (back.control_[i]);
- for (int i = 0; i < 4; i++)
- scontrols[i + 4] = ly_offset2scm (curve.control_[i]);
-
- /*
- Need the weird order b.o. the way PS want its arguments
- */
- int indices[] = {5, 6, 7, 4, 1, 2, 3, 0};
- SCM list = SCM_EOL;
- for (int i = 8; i--;)
- list = scm_cons (scontrols[indices[i]], list);
-
- SCM at = (scm_list_n (ly_symbol2scm ("bezier-sandwich"),
- ly_quote_scm (list),
- scm_from_double (linethick),
- SCM_UNDEFINED));
- Box b (curve.extent (X_AXIS),
- curve.extent (Y_AXIS));
-
- b[X_AXIS].unite (back.extent (X_AXIS));
- b[Y_AXIS].unite (back.extent (Y_AXIS));
-
- b.widen (0.5 * linethick, 0.5 * linethick);
- return Stencil (b, at);
+
+ if (!scm_is_pair (dash_details))
+ {
+ /* solid slur */
+ return_value = bezier_sandwich (back, curve, linethick);
+ }
+ else
+ {
+ /* dashed or combination slur */
+ int num_segments = scm_to_int (scm_length (dash_details));
+ for (int i=0; i<num_segments; i++)
+ {
+ SCM dash_pattern = scm_list_ref (dash_details, scm_from_int (i));
+ Real t_min = robust_scm2double (scm_car (dash_pattern), 0);
+ Real t_max = robust_scm2double (scm_cadr (dash_pattern), 1.0);
+ Real dash_fraction =
+ robust_scm2double (scm_caddr (dash_pattern), 1.0);
+ Real dash_period =
+ robust_scm2double (scm_cadddr (dash_pattern), 0.75);
+ Bezier back_segment = back.extract (t_min, t_max);
+ Bezier curve_segment = curve.extract (t_min, t_max);
+ if (dash_fraction == 1.0)
+ return_value.add_stencil (bezier_sandwich (back_segment,
+ curve_segment,
+ linethick));
+ else
+ {
+ Bezier back_dash, curve_dash;
+ Real seg_length = (back_segment.control_[3] -
+ back_segment.control_[0]).length ();
+ int pattern_count = seg_length / dash_period;
+ Real pattern_length = 1.0 / (pattern_count + dash_fraction);
+ Real start_t, end_t;
+ for (int p = 0; p <= pattern_count; p++)
+ {
+ start_t = p * pattern_length;
+ end_t = (p + dash_fraction) * pattern_length;
+ back_dash =
+ back_segment.extract (start_t, end_t);
+ curve_dash =
+ curve_segment.extract (start_t, end_t);
+ return_value.add_stencil (bezier_sandwich (back_dash,
+ curve_dash,
+ linethick));
+ }
+ }
+ }
+ }
+ return return_value;
}
+
/*
* Bezier Sandwich:
*
*
*/
Stencil
-Lookup::bezier_sandwich (Bezier top_curve, Bezier bottom_curve)
+Lookup::bezier_sandwich (Bezier top_curve, Bezier bottom_curve, Real thickness)
{
/*
Need the weird order b.o. the way PS want its arguments
SCM horizontal_bend = scm_list_n (ly_symbol2scm ("bezier-sandwich"),
ly_quote_scm (list),
- scm_from_double (0.0),
+ scm_from_double (thickness),
SCM_UNDEFINED);
Interval x_extent = top_curve.extent (X_AXIS);
y_extent.unite (bottom_curve.extent (Y_AXIS));
Box b (x_extent, y_extent);
+ b.widen (0.5 * thickness, 0.5 * thickness);
return Stencil (b, horizontal_bend);
}