Re: Determining location of the staff lines

[Carl Sorensen]

On 2/3/10 8:32 PM, "Eric Knapp" <address@hidden> wrote:

> Hi, everyone.
> 
> I'm working on developing StaffTab notation for the Chapman Stick. I
> have attached an image that shows something I need to do. In a Scheme
> engraver, I can get the string number that was notated. Then I need to
> be able to draw the little rectangle on the staff to indicate which
> string the composer suggests for this note. How do I know where the
> location of the staff lines are so I can draw that rectangle?

You don't know the location of the staff lines, and you don't worry about
the location of the staff lines.  You just need to set the staff-position
property of the grob, and the layout engine takes care of it like magic.

See lily/tab-note-heads-engraver.cc for an example, where the tab-note-head
is placed according to its string number.

HTH,

Carl