### 3.1.40 DynamicTextSpanner

DynamicTextSpanner objects are created by: Dynamic_engraver.

Standard settings:

> `before-line-breaking` (boolean):

>   `dynamic-text-spanner::before-line-breaking`

>   Dummy property, used to trigger a callback function.

> `bound-details` (list):

>   `'((right (attach-dir . -1) (Y . 0) (padding . 0.75)) (right-broken (attach-dir . 1) (padding . 0.0)) (left (attach-dir . -1) (Y . 0) (stencil-offset -0.75 . -0.5) (padding . 0.75)) (left-broken (attach-dir . 1)))`

>   An alist of properties for determining attachments of spanners to edges.

> `dash-fraction` (number):

>   `0.2`

>   Size of the dashes, relative to `dash-period`. Should be between `0.0` (no line) and `1.0` (continuous line).

> `dash-period` (number):

>   `3.0`

>   The length of one dash together with whitespace. If negative, no line is drawn at all.

> `font-shape` (symbol):

>   `'italic`

>   Select the shape of a font. Choices include `upright`, `italic`, `caps`.

> `font-size` (number):

>   `1`

>   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.

> `left-bound-info` (list):

>   `ly:line-spanner::calc-left-bound-info-and-text`

>   An alist of properties for determining attachments of spanners to edges.

> `minimum-length` (dimension, in staff space):

>   `2.0`

>   Try to make a spanner at least this long, normally in the horizontal direction. This requires an appropriate callback for the `springs-and-rods` property. If added to a `Tie`, this sets the minimum distance between noteheads.

> `minimum-Y-extent` (pair of numbers):

>   `'(-1 . 1)`

>   Minimum size of an object in Y dimension, measured in `staff-space` units.

> `right-bound-info` (list):

>   `ly:line-spanner::calc-right-bound-info`

>   An alist of properties for determining attachments of spanners to edges.

> `skyline-horizontal-padding` (number):

>   `0.2`

>   For determining the vertical distance between two staves, it is possible to have a configuration which would result in a tight interleaving of grobs from the top staff and the bottom staff. The larger this parameter is, the farther apart the staves are placed in such a configuration.

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

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

>   Dummy variable for triggering spacing routines.

> `stencil` (stencil):

>   `ly:line-spanner::print`

>   The symbol to print.

> `style` (symbol):

>   `'dashed-line`

>   This setting determines in what style a grob is typeset. Valid choices depend on the `stencil` callback reading this property.

> `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): dynamic-interface, dynamic-text-spanner-interface, font-interface, grob-interface, line-interface, line-spanner-interface, spanner-interface and text-interface.

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