2008/8/14 Carl D. Sorensen <[EMAIL PROTECTED]>: > Valentin, you made my day. To have somebody asking _me_ questions > about LilyPond programming is a first. I've been the one asking > everybody else questions. Thanks!
Well, had I known it would make your day, I'd have spent less time looking at your code and asked my question sooner :-) > You really don't want to get in the string business for this case. > It's much easier to just pass one argument to the function, a > list of pedal values. Oh yeah! Stupid, stupid me. I simply forgot about the list type. > If you really want to do this (why would users want to have values > greater than 1 or less than -1? I don't know harp music, so I can't say), You have a point. However, what Reinhold proposes is even sexier (see below). > This requires you to use lambda expressions, which are kind of confusing. Are lambda expressions related to http://en.wikipedia.org/wiki/Lambda_calculus? If so, I have to confess I kinda gave up every time I tried to read the Wikipedia page... :( > If you're going to do scheme programming with lilypond, lambda functions > are your friends, even though they can be confusing. I'll try harder then... > At the time I wrote fret-diagrams, constants like 4, 2, and 0.4 > were frowned upon. So I used variables connected to properties > every time I needed a constant like this, and there was concern about > polluting the property name space, so I created fret-diagram-details. Yes indeed. > Also, LilyPond coding standards call for using full words rather than > abbreviations for variable names. x, y, a, b and so forth should only > be used as part of a lambda function definition. Actually, d c b and so on referred to the note of the pedals. > With make-pedal-stencil defined you can now add a new variable to your let > assignment list [...] > And before your code to add stencils you can do a for-each: [...] > Which should glue all of your pedal stencils together in one big > stencil pedals-stencil. Great! This definitely looks good. > I think it's good for you to figure out how it works, so I've left the > debugging to you. If you have more questions, feel free to ask. I guess I will, pretty soon :) Many thanks anyway. 2008/8/14 Reinhold Kainhofer <[EMAIL PROTECTED]>: > Nice to see that I'm not the only one interested in implementing harp pedal > diagrams > (http://www.mail-archive.com/lilypond-devel%40gnu.org/msg15542.html). Oh yes, I remember now that you had asked for possible glyphs. > I think the easiest and most Scheme-like way would be to loop through the > seven entries of the pedal list using recursive calls of a named let > clause... In particular: The problem is that the pedal boxes are not evenly spaced (there are three on one side, four on the other). > Actually, each entry in a harp diagram can only have three values, so I don't > like numeric representations too much (internally, lilypond uses integers for > directions, but that is hidden from the user as much as possible by #UP etc. > I don't think the users should be exposed to numbers as directions in harp > diagrams). What I was thinking of was a rough textual representation of the > states: > \harpPedals #"^--|v-^-" such a string with one letter per pedal is much easier > to parse. This is just awesome! Can it be handled by pure Scheme though, or does this need to be dealt with on the C++ side? > Of course, we can have two versions, a terse one with #"^--|v-^-" > and a "normal" one with "1;0;0;-1;0;1;0". That's just a matter of two > different string parsers before the same function is called, similar to the > fret-parse-definition-string function and the subsequent call to the function > that really generates the fret diagram. This looks really, really cool, though way beyond my knowledge. Nice to have some "real" people on my side, anyway :-) Cheers, Valentin _______________________________________________ lilypond-user mailing list lilypond-user@gnu.org http://lists.gnu.org/mailman/listinfo/lilypond-user
