### 3.2.6 arpeggio-interface

Functions and settings for drawing an arpeggio symbol.

#### User settable properties:

> `arpeggio-direction` (direction)

>   If set, put an arrow on the arpeggio squiggly line.

> `dash-definition` (pair)

>   List of `dash-elements` defining the dash structure. Each `dash-element` has a starting t value, an ending t-value, a `dash-fraction`, and a `dash-period`.

> `positions` (pair of numbers)

>   Pair of staff coordinates `(left . right)`, where both left and right are in `staff-space` units of the current staff. For slurs, this value selects which slur candidate to use; if extreme positions are requested, the closest one is taken.

> `protrusion` (number)

>   In an arpeggio bracket, the length of the horizontal edges.

> `script-priority` (number)

>   A key for determining the order of scripts in a stack, by being added to the position of the script in the user input, the sum being the overall priority. Smaller means closer to the head.

#### Internal properties:

> `stems` (array of grobs)

>   An array of stem objects.

This grob interface is used in the following graphical object(s): Arpeggio.

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