### 3.1.110 StemTremolo

StemTremolo objects are created by: Stem_engraver.

Standard settings:

> `beam-thickness` (dimension, in staff space):

>   `0.48`

>   Beam thickness, measured in `staff-space` units.

> `beam-width` (dimension, in staff space):

>   `ly:stem-tremolo::calc-width`

>   Width of the tremolo sign.

> `direction` (direction):

>   `ly:stem-tremolo::calc-direction`

>   If `side-axis` is `0` (or `X`), then this property determines whether the object is placed `LEFT`, `CENTER` or `RIGHT` with respect to the other object. Otherwise, it determines whether the object is placed `UP`, `CENTER` or `DOWN`. Numerical values may also be used: `UP`=`1`, `DOWN`=`-1`, `LEFT`=`-1`, `RIGHT`=`1`, `CENTER`=`0`.

> `slope` (number):

>   `ly:stem-tremolo::calc-slope`

>   The slope of this object.

> `stencil` (stencil):

>   `ly:stem-tremolo::print`

>   The symbol to print.

> `style` (symbol):

>   `ly:stem-tremolo::calc-style`

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

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

>   `ly:stem-tremolo::width`

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

> `X-offset` (number):

>   `#<simple-closure (#<primitive-generic +> #<simple-closure (#<primitive-procedure ly:self-alignment-interface::centered-on-x-parent>) > #<simple-closure (#<primitive-procedure ly:self-alignment-interface::x-aligned-on-self>) >) >`

>   The horizontal amount that this object is moved relative to its X-parent.

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

>   `#<unpure-pure-container #<primitive-procedure ly:grob::stencil-height> #<primitive-procedure ly:stem-tremolo::pure-height> >`

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

> `Y-offset` (number):

>   `#<unpure-pure-container #<primitive-procedure ly:stem-tremolo::calc-y-offset> #<primitive-procedure ly:stem-tremolo::pure-calc-y-offset> >`

>   The vertical amount that this object is moved relative to its Y-parent.

This object supports the following interface(s): grob-interface, item-interface, self-alignment-interface and stem-tremolo-interface.

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