Jean Abou Samra <j...@abou-samra.fr> writes: > Le 10/02/2022 à 15:42, Simon Albrecht a écrit : >> Hi Aaron, >> >> thanks a lot for the help! I knew that these pure vs. impure issues >> exist, but I’ve never been able to wrap my head around them and this >> is the first time I ever needed to account for them in practice. >> >> Looking at Extending Manual section 2.8, it seems that Y-offset is >> likely to be affected, so that makes sense. >> >> What I don’t quite get is the meaning of the ‘begin’ and ‘end’ >> parameters in ly:grob-pure-property, but as long as 0 0 works, I’m >> good ;) (and it’s not a topic for the bug list) >> >> Best, Simon > > > > Sorry, I just received this message now so my previous reply didn't > account for it (yes, list messages are taking 5 hours to reach > recipients sometimes, this was discussed recently on lilypond-user). > > So, to answer your question, start and end are column ranks. > The meaning of the question (ly:grob-pure-property grob start end) > is "What will this grob property approximately on the broken > piece if this spanner is broken between start and end?"
Not the way I understand things. The question is "What will this grob property be in a line that starts in column `start` and ends in column `end`. That spanners consist of broken pieces is a different complication not specifically related to start/end. > (for items they should be ignored). I don't see that. Even items may have different properties depending on start/end. For example, accidental rules should be taking them into account (but don't currently) since accidentals on notes tied over bars get repeated after a line break (and then don't need another repetition). > They are used in VerticalAxisGroup pure calculations, to estimate how > tall a staff will be between two certain points in order to score page > breaking configurations. Yes, that's more like it. -- David Kastrup _______________________________________________ bug-lilypond mailing list bug-lilypond@gnu.org https://lists.gnu.org/mailman/listinfo/bug-lilypond