### 3.1.123 Tie

Tie objects are created by: Completion_heads_engraver and Tie_engraver.

Standard settings:

> `avoid-slur` (symbol):

>   `'inside`

>   Method of handling slur collisions. Choices are `inside`, `outside`, `around`, and `ignore`. `inside` adjusts the slur if needed to keep the grob inside the slur. `outside` moves the grob vertically to the outside of the slur. `around` moves the grob vertically to the outside of the slur only if there is a collision. `ignore` does not move either. In grobs whose notational significance depends on vertical position (such as accidentals, clefs, etc.), `outside` and `around` behave like `ignore`.

> `control-points` (list):

>   `ly:tie::calc-control-points`

>   List of offsets (number pairs) that form control points for the tie, slur, or bracket shape. For Béziers, this should list the control points of a third-order Bézier curve.

> `details` (list):

>   `'((ratio . 0.333) (center-staff-line-clearance . 0.6) (tip-staff-line-clearance . 0.45) (note-head-gap . 0.2) (stem-gap . 0.35) (height-limit . 1.0) (horizontal-distance-penalty-factor . 10) (same-dir-as-stem-penalty . 8) (min-length-penalty-factor . 26) (tie-tie-collision-distance . 0.45) (tie-tie-collision-penalty . 25.0) (intra-space-threshold . 1.25) (outer-tie-vertical-distance-symmetry-penalty-factor . 10) (outer-tie-length-symmetry-penalty-factor . 10) (vertical-distance-penalty-factor . 7) (outer-tie-vertical-gap . 0.25) (multi-tie-region-size . 3) (single-tie-region-size . 4) (between-length-limit . 1.0))`

>   Alist of parameters for detailed grob behavior. More information on the allowed parameters for a grob can be found by looking at the top of the Internals Reference page for each interface having a `details` property.

> `direction` (direction):

>   `ly:tie::calc-direction`

>   If `side-axis` is `0` (or `X`), then this property determines whether the object is placed `LEFT`, `CENTER` or `RIGHT` with respect to the other object. Otherwise, it determines whether the object is placed `UP`, `CENTER` or `DOWN`. Numerical values may also be used: `UP`=`1`, `DOWN`=`-1`, `LEFT`=`-1`, `RIGHT`=`1`, `CENTER`=`0`.

> `font-size` (number):

>   `-6`

>   The font size, compared to the ‘normal’ size. `0` is style-sheet’s normal size, `-1` is smaller, `+1` is bigger. Each step of 1 is approximately 12% larger; 6 steps are exactly a factor 2 larger. Fractional values are allowed.

> `line-thickness` (number):

>   `0.8`

>   The thickness of the tie or slur contour.

> `neutral-direction` (direction):

>   `1`

>   Which direction to take in the center of the staff.

> `springs-and-rods` (boolean):

>   `ly:spanner::set-spacing-rods`

>   Dummy variable for triggering spacing routines.

> `stencil` (stencil):

>   `ly:tie::print`

>   The symbol to print.

> `thickness` (number):

>   `1.2`

>   Line thickness, generally measured in `line-thickness`.

> `vertical-skylines` (pair of skylines):

>   `#<unpure-pure-container #<primitive-procedure ly:grob::vertical-skylines-from-stencil> #<primitive-procedure ly:grob::pure-simple-vertical-skylines-from-extents> >`

>   Two skylines, one above and one below this grob.

This object supports the following interface(s): grob-interface, spanner-interface and tie-interface.

#### Internals Reference v2.18.2 (稳定分支).