### 3.1.5 Ambitus

Ambitus objects are created by: Ambitus_engraver.

Standard settings:

> `axes` (list):

>   `'(0 1)`

>   List of axis numbers. In the case of alignment grobs, this should contain only one number.

> `break-align-symbol` (symbol):

>   `'ambitus`

>   This key is used for aligning and spacing breakable items.

> `break-visibility` (vector):

>   `#(#f #f #t)`

>   A vector of 3 booleans, `#(end-of-line unbroken begin-of-line)`. `#t` means visible, `#f` means killed.

> `non-musical` (boolean):

>   `#t`

>   True if the grob belongs to a `NonMusicalPaperColumn`.

> `space-alist` (list):

>   `'((cue-end-clef extra-space . 0.5) (clef extra-space . 0.5) (cue-clef extra-space . 0.5) (key-signature extra-space . 0.0) (staff-bar extra-space . 0.0) (time-signature extra-space . 0.0) (first-note fixed-space . 0.0))`

>   A table that specifies distances between prefatory items, like clef and time-signature. The format is an alist of spacing tuples: `(break-align-symbol type . distance)`, where type can be the symbols `minimum-space` or `extra-space`.

> `X-extent` (pair of numbers):

>   `ly:axis-group-interface::width`

>   Extent (size) in the X direction, measured in staff-space units, relative to object’s reference point.

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

>   `#<unpure-pure-container #<primitive-procedure ly:axis-group-interface::height> #<primitive-procedure ly:axis-group-interface::pure-height> >`

>   Extent (size) in the Y direction, measured in staff-space units, relative to object’s reference point.

This object supports the following interface(s): ambitus-interface, axis-group-interface, break-aligned-interface, grob-interface and item-interface.

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