2015-10-07 13:13 GMT+02:00 David Kastrup <d...@gnu.org>: >> Thomas Morley <thomasmorle...@gmail.com> writes:
>> I think we could replace the body of current >> make-bezier-sandwich-stencil with make-path-stencil. >> But obviously you think about some deeper modification. >> Could you give some details? > > No, not really. When I tabled this issue, I thought that > make-bezier-sandwich was dead for some reason but I think that it's used > in several places such as (obviously related) slurs. Well: git grep make-bezier-sandwich-stencil scm/fret-diagrams.scm: (make-bezier-sandwich-stencil scm/stencil.scm:(define (make-bezier-sandwich-stencil coords thick xext yext) scm/stencil.scm: (make-bezier-sandwich-stencil Not much. > And I found it > awkward to use the undertie as the basic shape and derive parentheses > via rotation. The code in my initial mail uses coord-rotate (not ly:stencil-rotate-absolute as in Jans suggestion) What do you think about this method? Ofcourse it was heavily simplified, maybe best to put up a patch to have the full code for more detailed discussion. > And I thought this was essentially user-level code > needing significant modification. > > All in all, I had a significant number of misconceptions about the work > involved with completing this issue and even though becoming gradually > aware of them I never picked up that dropped ball again. > > It should be reasonably low-hanging fruit. > > With regard to my comments to make-path-stencil's operation, the numeric > code is just not what I like. > > If you take a look at the following, it is quite inefficient since it > repeats a lot of calculations instead of assigning partial results to > let-bound variables. It also uses the straight PQ formula whereas the > usual way to avoid numerical inaccuracies is to use the PQ formula only > for the zero where the sign of the +/- does not lead to cancellation and > get the other zero via Viata's rule. > > (define (bezier-part-min-max x1 x2 x3 x4) [...] No promise, but maybe I'll take a look. Not that I know about Viata's or L'hopital's rule, but google maybe helpfull, otherwise I'll reask Cheers, Harm _______________________________________________ lilypond-user mailing list lilypond-user@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-user