Am 27.04.2012 19:30, schrieb David Nalesnik:
Hi Urs,
On Fri, Apr 27, 2012 at 11:46 AM, Urs Liska <li...@ursliska.de
<mailto:li...@ursliska.de>> wrote:
Hi David,
thank you for now. I'll look into it.
But isn't it very likely that I have to reshape a slur anyway when
it changes from broken to unbroken?
In that case I'd even say the errors are a 'feature' so you notice
it ...
Provided it is documented enough not to drive you crazy ...
Sure, that's true. Presumably when you're looking for that fine
control, you've settled on the layout in all but the tiny details!
it's not only this. I think that with any slur that one might decide to
shape manually a change in line break will spoil it anyway. So I'm not
so sure it's a useful goal to make such a function fool-proof in this
respect.
Without the modification, though, the error would cause the file to
fail and the error message is a little opaque. (Well, it's quite
exact, but it takes some study to figure out how it happened.)
Well, the file fails (at least lilypond says so), but it actually
compiles, it's only the function that isn't applied. But you're right to
assume that the normal user can't cope with the error messages ;-)
I could create a warning here, something like: "slur is not broken
anymore".
If that's possible in such functions, I'd find it very useful. Even
better: tell the user: "The slur has now X parts, please adapt the
function call"
One thing you can do is
\shapeSlur #'( ... list of offsets ...)
or
\shapeSlur #'(( ... list of offsets ...))
without the file failing.
Since this function has come up again, I wonder if I could get your
(and other people's) opinion on syntax. When I first wrote the
offsetting function (http://lsr.dsi.unimi.it/LSR/Item?id=639)I
<http://lsr.dsi.unimi.it/LSR/Item?id=639%29I> thought that alists were
a bother to type. But 'control-pojnts _is_ an alist '((x1 . y1) (x2 .
y2) ... )) , so shouldn't we have something like this?
\shapeSlur #'((dx1 . dy1) (dx2 . dy2) ...)
I realize that there's more to type, but wouldn't this be clearer to
use? (As well as being more consistent with how LilyPond represents
this type of data)?
First: I think this is a _very_ useful function that should even be made
more widely known. The need to shape slurs is one of the most important
issues when it comes to the major problems of a LilPond score. Not
because it's a deficit of LilyPond but because it's a very complex topic
that needs human intervention in most cases.
Second: your syntax suggestion looks very good to me.
Of course it is more to type. But that is more than outweighed by the
advantages. it's easier to write and it's especially much easier to
read. When changing the offsets (which you do multiple times until you
get a good result ...) I'm always finding me counting params (in order
to find the right item to change) which surely takes more time and
concentration than typing (once) a few brackets and points.
Third: I suggest to add support for PhrasingSlurs and Ties in order to
make it more general. For PhrasingSlurs it's just a matter of writing a
new entrance function, but for Ties you need new shape-ties and
alter-tie-curve subroutines. See the attached file that is the result of
an earlier enquiry on this mailing list.
The functions themselves don't incorporate your newest additions (sorry,
it's still a bit over my head), but you'll see what I mean.
Any thoughts?
to sum up what I said:
If you'd volunteer to do the following it would be a very valuable
contribution to LilyPond's usability ;-)
- let the function check the number of arguments and give meaningful
warnings instead of errors
(count arguments and compare against number of slur siblings)
- don't try to make the function robust so that it accepts wrong input.
This may be trivial from a programmer's perspective but I can't imagine
that it makes sense aesthetically.
- add support for phrasingSlurs and ties
- make all this visible, at least through an updated snippet in the LSR.
Personally I think this should also be in the docs.
With best wishes
Urs
-David
_______________________________________________
lilypond-user mailing list
lilypond-user@gnu.org
https://lists.gnu.org/mailman/listinfo/lilypond-user
%{
shapeXXX.ily
base include file with typographic tweaks
modifing the shapes of Bezier curved spanners.
Provided by Urs Liska (m...@ursliska.de)
Exported functions:
- shapeSlur
- shapePhrasingSlur
- shapeTie
This version works also with line broken curves
and modifies the shapes of the siblings individually
Usage: \shapeXXX (offsets) music
offset is a list of eight numbers indicating the x and y offsets
for the four control-points of the curve
for each part of a broken slur one can give a separate list.
An empty list means that the respective slur isn't altered
in contrast to overriding the control-points property
this function takes offsets relative to LilyPond's
default decision. So the function can often be left
unaltered even when the layout changes slightly
example for a single slur:
\shapeSlur #'( 0 0 3 -1 6 2 -5 0 ) ...
example for a broken phrasing slur
\shapePhrasingSlur #'(
(0 1 0 0 0 -4 0 2)
(4 3 2 5 -1 4 0 0)
() % Don't change the third part
) ...
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
The first version of a shapeSlur function was developed by Neil Puttock
(see http://lists.gnu.org/archive/html/lilypond-user/2009-09/msg00495.html)
Another version was added to the Lilypond Snippet Repository
(see http://lsr.dsi.unimi.it/LSR/Snippet?id=639)
Later the function was enhanced to deal with broken slurs
by Dmytro O. Redchuk and David Nalesnik (don't know exactly how)
(see http://permalink.gmane.org/gmane.comp.gnu.lilypond.general/65612)
With the help of the lilypond-user mailing list I finally
adapted the function to also work with Ties and polished the file to
export the three functions
One thing which is still missing is the ability of the function to
automatically react when a slur is broken / unbroken
as a reaction to changed line breaks
At the moment (August 2011) there seems to be a discussion about
whether to include this function to the LSR or the docs
or even to LilyPond
%}
\version "2.14.0"
#(define ((alter-slur-curve offsets) grob)
;; get default control-points
(let ((coords (ly:slur::calc-control-points grob)))
;; add offsets to default coordinates
(define (add-offsets coords offsets)
(if (null? coords)
'()
(cons
(cons (+ (caar coords) (car offsets))
(+ (cdar coords) (cadr offsets)))
(add-offsets (cdr coords) (cddr offsets)))))
(if (null? offsets)
coords
(add-offsets coords offsets))))
#(define ((shape-slur offsets) grob)
(let* (
;; have we been split?
(orig (ly:grob-original grob))
;; if yes, get the split pieces (our siblings)
(siblings (if (ly:grob? orig)
(ly:spanner-broken-into orig) '() ))
(total-found (length siblings)))
(if (>= total-found 2)
;; shape BROKEN
;; walk through siblings, find index in list
;; and apply offsets from list of offsets:
(let loop ((n 0))
(if (eq? (list-ref siblings n) grob)
;; return altered:
((alter-slur-curve (list-ref offsets n)) grob)
(if (< n total-found)
(loop (1+ n))
;; end of list -- none found?!
;; return defaults:
((alter-slur-curve '()) grob))))
;;
;; shape UNBROKEN
((alter-slur-curve offsets) grob))))
% Changed function to shape ties
#(define ((alter-tie-curve offsets) grob)
;; get default control-points
(let ((coords (ly:tie::calc-control-points grob)))
;; add offsets to default coordinates
(define (add-offsets coords offsets)
(if (null? coords)
'()
(cons
(cons (+ (caar coords) (car offsets))
(+ (cdar coords) (cadr offsets)))
(add-offsets (cdr coords) (cddr offsets)))))
(if (null? offsets)
coords
(add-offsets coords offsets))))
#(define ((shape-tie offsets) grob)
(let* (
;; have we been split?
(orig (ly:grob-original grob))
;; if yes, get the split pieces (our siblings)
(siblings (if (ly:grob? orig)
(ly:spanner-broken-into orig) '() ))
(total-found (length siblings)))
(if (>= total-found 2)
;; shape BROKEN
;; walk through siblings, find index in list
;; and apply offsets from list of offsets:
(let loop ((n 0))
(if (eq? (list-ref siblings n) grob)
;; return altered:
((alter-tie-curve (list-ref offsets n)) grob)
(if (< n total-found)
(loop (1+ n))
;; end of list -- none found?!
;; return defaults:
((alter-tie-curve '()) grob))))
;;
;; shape UNBROKEN
((alter-tie-curve offsets) grob))))
shapePhrasingSlur =
#(define-music-function (parser location offsets)
(list?)
#{
\once \override PhrasingSlur #'control-points = #(shape-slur offsets)
#})
shapeSlur =
#(define-music-function (parser location offsets)
(list?)
#{
\once \override Slur #'control-points = #(shape-slur offsets)
#})
shapeTie =
#(define-music-function (parser location offsets)
(list?)
#{
\once \override Tie #'control-points = #(shape-tie offsets)
#})
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
_______________________________________________
lilypond-user mailing list
lilypond-user@gnu.org
https://lists.gnu.org/mailman/listinfo/lilypond-user
