tisimst <tisimst.lilypond <at> gmail.com> writes: > > Kieren MacMillan wrote > > Any hints, for example, on what ‘ratio' actually does, or [..] > effect of "ratio". Seems like a "bug" to me that increasing "ratio" > doesn't > change the shape of the tie curve very much if the tie is at its > "height-limit", but maybe it's my ignorance at play here.
I traced through the function calls to 'ly/bezier-bow.cc' where the curve of the tie is formed. This is old code and not the best among LilyPonds code, with spaghetti-like paths of function calls. I decided not to trust the comments. From reading the code it looks like: 'ratio' is the aspect ratio, height to width, for short ties and slurs but as ties get longer the aspect ratio is reduced so the height (of the control points, a bit less than that of the curve) remains below 'height-limit'. These are bezier curves with four control points. Short ties and slurs have the four control points equally-spaced along their length. As ties get longer the middle control points stay relatively closer to the endpoints, never getting further than twice the 'height-limit' from the end points. The transitions from short-tie to long-tie shape are smooth. I'll try to test a bit to see if LilPond behaves as reading the code makes me expect. The other details seem to deal with placing ties relative to the other music. 1) To make a tie more parabolic, I would want to move the control points toward the center. I don't see a parameter for that, but maybe someone can see how to make a scheme hook for calc-control-points that adjusts the horizontal spacing of these points. I think that could integrate well with the other placement code. Slurs have a parameter 'eccentricity' that moves control points horizontally and might be a good model. 2) The text in the docstrings could maybe be interpreted in a way consistent with behavior, but it seems they could be written much more directly (if I got it right above). _______________________________________________ lilypond-user mailing list lilypond-user@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-user
