On Tue, 2023-12-12 at 16:10 -0800, Stefano Antonelli wrote: > I'm producing muliple pngs with a single staff each. When I 'flip' > through these pngs, the staff appears to move up and down on the > page. > > I can set > > top-system-spacing.basic-distance = #7
It turns out I need exactly top-system-spacing.basic-distance = #6 To get the middle staff line positioned at the vertical centre. See attached. The paper-height is 14.8 and the centre should be at 7.4 "systems spacing". If I want to put the middle staff line there I need: top-system-spacing.basic-distance = paper-height/2 - 1.4 That 1.4 is referenced to the "vertical center of the nearest StaffSymbol when there is no markup between the system and the top margin". As it is in my case. The StaffSymbol, is just the 5 (by default) lines of the staff according to here: <http://lilypond.org/doc/v2.25/Documentation/internals/staffsymbol> If the vertical centre was really the vertical centre (ie. the middle staff line), then my calculation would change to: top-system-spacing.basic-distance = paper-height/2 And life would be good. Even if it were the top staff line: top-system-spacing.basic-distance = paper-height/2 - 2 would do it. I don't understand where 1.4 comes from or how to calculate it based on the staff-size. Is there a way to ask lilypond what the "vertical center of the nearest StaffSymbol" is? This seems like a roundabout way to get the middle staff line to the vertical centre of the page. Is there an easier way? The vertical centre has the advantage/disadvantage of equal space for beams above and below the staff. If the beams don't fit one way or the other the page height has to be increased. And that's a trial and error approach. Ideally, the max height of the systems on all pages would be considered and all the systems could be placed so that there is the maximum amount of available space for beams, where they are needed, over the whole score. This could probably be done by running lilypond once with #one- line-auto-height-breaking and dumping certain variables to the screen or a file. I don't have time to play with that right now though. Also related, I can calculate the paper-height in "system spacing" from the height in mm. Is there a way to get this number in "system spacing" directly from lilypond such that I could use it to set top- system-spacing.basic-distance? Thanks, Stef
