Doc: NR 5.5.4 - Modifying ties and slurs

[lilypond.git] / Documentation / notation / changing-defaults.itely

diff --git a/Documentation/notation/changing-defaults.itely b/Documentation/notation/changing-defaults.itely
index 7f1bb0f0a0b790d8c051b4f97b2d947ad6968797..14847f8c162a9eb57b9316358d2ba31027a8499d 100644 (file)
--- a/Documentation/notation/changing-defaults.itely
+++ b/Documentation/notation/changing-defaults.itely
@@ -3622,33 +3622,35 @@ Notation Reference:
 
 @cindex slurs, modifying
 @cindex ties, modifying
-@cindex Bézier curves
-@cindex Bézier control points
-
-Ties, slurs and phrasing slurs are drawn as third-order Bézier
-curves.  If the shape of the tie or slur which is calculated
-automatically is not optimum, the shape may be modified manually by
-explicitly specifying the four control points required to define
-a third-order Bézier curve.
-
-Third-order or cubic Bézier curves are defined by four control
-points.  The first and fourth control points are precisely the
-starting and ending points of the curve.  The intermediate two
-control points define the shape.  Animations showing how the curve
-is drawn can be found on the web, but the following description
-may be helpful.  The curve starts from the first control point
-heading directly towards the second, gradually bending over to
-head towards the third and continuing to bend over to head towards
-the fourth, arriving there travelling directly from the third
-control point.  The curve is entirely contained in the
-quadrilateral defined by the four control points.
-
-Here is an example of a case where the tie is not optimum, and
-where @code{\tieDown} would not help.
+@cindex Bézier curves, control points
+@cindex control points, Bézier curves
+
+If the shape of the tie or slur which is calculated automatically is not
+optimum, the shape may be modified manually by explicitly specifying the
+control points required to define the curve needed.
+
+Ties, slurs and phrasing slurs are drawn as @q{third-order} Bézier
+curves which are are defined by four control points.  The first and
+fourth control points are the start and end points of the curve
+respectively, and the two intermediate control points define the
+overall shape.
+
+Animations showing how the curve is drawn can be found on the web, but
+the following description may be helpful.  The curve starts from the
+first control point moving towards the second.  As the curve nears and
+passes through the second control point it begins to arc towards the
+third.  The curve continues on towards the the third control point,
+again starting to arc as it nears and passes through the third so as to
+finish the curve smoothly at the fourth and final control point.  The
+whole curve is contained in the quadrilateral defined by the four
+control points.
+
+Here is an example of a case where the tie is not optimum (and where the
+@code{\tieDown} command would not help).
 
 @lilypond[verbatim,quote,relative=1]
 <<
-  { e1 ~ e }
+  { e1~ e }
 \\
   { r4 <g c,> <g c,> <g c,> }
 >>
@@ -3681,23 +3683,24 @@ to which the start of the tie (or slur) is attached.
   {
     \once \override Tie
       #'control-points = #'((1 . -1) (3 . 0.6) (12.5 . 0.6) (14.5 . -1))
-     e1 ~ e1
+     e1 ~ e
   }
 \\
-  { r4 <g c,> <g c,> <g c,>4  }
+  { r4 <g c,> <g c,> <g c,> }
 >>
 @end lilypond
 
 @knownissues
-
 It is not possible to modify shapes of ties or slurs by changing
-the @code{control-points} property if there are more than one at
-the same musical moment, not even by using the @code{\tweak}
-command.  However, the @code{tie-configuration} property of
-@code{TieColumn} can be overridden to set start line and direction
-of ties as required.
-
+the @code{control-points} property if there are multiple ties or slurs
+at the same musical moment -- the @code{\tweak} command will also not
+work in this case.  However, the @code{tie-configuration} property of
+@code{tie-column-interface} can be overridden to set start line and
+direction of ties as required.
 
+@seealso
+Internals Reference:
+@rinternals{tie-column-interface}.
 
 
 @node Using music functions