LilyPond Internals Reference: 3.2.101 staff-grouper-interface

### 3.2.101 staff-grouper-interface

A grob that collects staves together.

#### User settable properties:

> `staff-staff-spacing` (list)

>   When applied to a staff-group’s `StaffGrouper` grob, this spacing alist controls the distance between consecutive staves within the staff-group. When applied to a staff’s `VerticalAxisGroup` grob, it controls the distance between the staff and the nearest staff below it in the same system, replacing any settings inherited from the `StaffGrouper` grob of the containing staff-group, if there is one. This property remains in effect even when non-staff lines appear between staves. The alist can contain the following keys:

>   - `basic-distance` – the vertical distance, measured in staff-spaces, between the reference points of the two items when no collisions would result, and no stretching or compressing is in effect.
>   - `minimum-distance` – the smallest allowable vertical distance, measured in staff-spaces, between the reference points of the two items, when compressing is in effect.
>   - `padding` – the minimum required amount of unobstructed vertical whitespace between the bounding boxes (or skylines) of the two items, measured in staff-spaces.
>   - `stretchability` – a unitless measure of the dimension’s relative propensity to stretch. If zero, the distance will not stretch (unless collisions would result).
> `staffgroup-staff-spacing` (list)

>   The spacing alist controlling the distance between the last staff of the current staff-group and the staff just below it in the same system, even if one or more non-staff lines exist between the two staves. If the `staff-staff-spacing` property of the staff’s `VerticalAxisGroup` grob is set, that is used instead. See `staff-staff-spacing` for a description of the alist structure.

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

#### Internals Reference