5.2.2 Layout interfaces

The HTML page that we found in the previous section describes the layout object called Fingering. Such an object is a symbol within the score. It has properties that store numbers (like thicknesses and directions), but also pointers to related objects. A layout object is also called a Grob, which is short for Graphical Object. For more details about Grobs, see grob-interface.

The page for Fingering lists the definitions for the Fingering object. For example, the page says

padding (dimension, in staff space):


which means that the number will be kept at a distance of at least 0.5 of the note head.

Each layout object may have several functions as a notational or typographical element. For example, the Fingering object has the following aspects

Each of these aspects is captured in so-called interfaces, which are listed on the Fingering page at the bottom

This object supports the following interfaces: item-interface, self-alignment-interface, side-position-interface, text-interface, text-script-interface, font-interface, finger-interface, and grob-interface.

Clicking any of the links will take you to the page of the respective object interface. Each interface has a number of properties. Some of them are not user-serviceable (‘Internal properties’), but others can be modified.

We have been talking of the Fingering object, but actually it does not amount to much. The initialization file (see Other sources of information) scm/define-grobs.scm shows the soul of the ‘object’,

  . ((padding . 0.5)
     (avoid-slur . around)
     (slur-padding . 0.2)
     (staff-padding . 0.5)
     (self-alignment-X . 0)
     (self-alignment-Y . 0)
     (script-priority . 100)
     (stencil . ,ly:text-interface::print)
     (direction . ,ly:script-interface::calc-direction)
     (font-encoding . fetaText)
     (font-size . -5) 		; don't overlap when next to heads.
     (meta . ((class . Item)
     (interfaces . (finger-interface

As you can see, the Fingering object is nothing more than a bunch of variable settings, and the web page in the Internals Reference is directly generated from this definition.

LilyPond Notation Reference v2.25.18 (development-branch).