+ assert (head_l_drul_[LEFT] || head_l_drul_[RIGHT]);
+
+ Real interline_f = paper_l ()->get_var ("interline");
+ Real internote_f = interline_f / 2;
+ Real x_gap_f = paper_l ()->get_var ("tie_x_gap");
+ Real y_gap_f = paper_l ()->get_var ("tie_y_gap");
+
+ /*
+ Slur and tie placement [OSU]
+
+ Ties:
+
+ * x = inner vertical tangent - d * gap
+
+ */
+
+
+ /*
+ OSU: not different for outer notes, so why all this code?
+ ie, can we drop this, or should it be made switchable.
+ */
+#if 0
+ Direction d = LEFT;
+ do
+ {
+ Real head_width_f = head_l_drul_[d]
+ ? head_l_drul_[d]->extent (X_AXIS).length ()
+ : 0;
+ /*
+ side attached to outer (upper or lower) notehead of chord
+ */
+ if (head_l_drul_[d]
+ /*
+
+ a~a~a;
+
+ to second tie, middle notehead seems not extremal
+
+ Getting scared a bit by score-element's comment:
+ // is this a good idea?
+ */
+ && (head_l_drul_[d]->get_elt_property ("extremal")
+ != SCM_UNDEFINED))
+ {
+ if (d == LEFT)
+ dx_f_drul_[d] += head_width_f;
+ dx_f_drul_[d] += -d * x_gap_f;
+ }
+ /*
+ side attached to inner notehead
+ */
+ else
+ {
+ dx_f_drul_[d] += -d * head_width_f;
+ }
+ } while (flip (&d) != LEFT);
+
+#else
+
+ if (head_l_drul_[LEFT])
+ dx_f_drul_[LEFT] = head_l_drul_[LEFT]->extent (X_AXIS).length ();
+ else
+ dx_f_drul_[LEFT] = get_broken_left_end_align ();
+ dx_f_drul_[LEFT] += x_gap_f;
+ dx_f_drul_[RIGHT] -= x_gap_f;
+
+#endif
+
+ /*
+ Slur and tie placement [OSU] -- check this
+
+ Ties:
+
+ * y = dx < 5ss: horizontal tangent
+ y = dx >= 5ss: y next interline - d * 0.25 ss
+
+ which probably means that OSU assumes that
+
+ dy <= 5 dx
+
+ for smal slurs
+ */
+
+ Real ypos = head_l_drul_[LEFT] ? head_l_drul_[LEFT]->position_f ()
+ : head_l_drul_[RIGHT]->position_f ();
+
+ Real y_f = internote_f * ypos;
+ int ypos_i = int (ypos);
+
+ Real dx_f = extent (X_AXIS).length () + dx_f_drul_[RIGHT] - dx_f_drul_[LEFT];
+ if (dx_f < paper_l ()->get_var ("tie_staffspace_length"))
+ {
+ if (abs (ypos_i) % 2)
+ y_f += get_direction () * internote_f;
+ y_f += get_direction () * y_gap_f;
+ }
+ else
+ {
+ if (! (abs (ypos_i) % 2))
+ y_f += get_direction () * internote_f;
+ y_f += get_direction () * internote_f;
+ y_f -= get_direction () * y_gap_f;
+ }
+
+ dy_f_drul_[LEFT] = dy_f_drul_[RIGHT] = y_f;
+}
+
+void
+Tie::do_substitute_element_pointer (Score_element*o, Score_element*n)
+{
+ Note_head *new_l = n ? dynamic_cast<Note_head *> (n) : 0;
+ if (dynamic_cast <Item *> (o) == head_l_drul_[LEFT])
+ head_l_drul_[LEFT] = new_l;
+ else if (dynamic_cast <Item *> (o) == head_l_drul_[RIGHT])
+ head_l_drul_[RIGHT] = new_l;