[lilypond.git] / TODO

-*-outline-layout:(2 (-1 -1 0 :) 0);outline-stylish-prefixes:nil -*-


* GNU LilyPond TODO
Features you cannot find in the documentation as working, should be
mentioned here.  This is an assorted collection of stuff that will be
done, might be done, or is an idea that we want to think about.
Most of the items are marked in the code as well
Grep -i for TODO, FIXME and ugh/ugr/urg.  

.* TODO
. * use hash tabs iso. alist_ for elt property?
. * alignment within @itemize
. * junk dstream output.
. * agressive type-checking for SCM stuff.
. * script columns
. * Must stop before this music ends:
verse=\lyrics {
. * input/bugs/clef.sly: clef changes go missing
. * input/test/grace.sly: wierd big spacing on grace notes
. * TODO^2:
.  * make  a TODO.texi, like http://www.gnu.org/software/guile/ideas.html
.  * make this file understandable for 3rd parties.
. * \accepts -> \acceptedby 
. * context in embedded SCM errors.
. * acc at tied note after linebreak.
. * fix font-naming and selecting
. * barcheck warning doesn't resync anymore
. * provide settable/invisible span-score-bar bracket
. * add context information to warnings
Paper:
waarschuwing: Kan niet beide uiteinden van bindingsboog vinden
MIDI:
pa.ly:33:23: waarschuwing: Schroot verzoek: `Span_req':
  g' a4 bes8 \grace f8(
                         )es16 d es8 r c |
. * sparse ties.
. * chord tonic: placement of accidental  C#, Cb (from scm and C++)
. * note head on stem err msg in dutch.
. * why need to run -C mf twice?
. * here's no difference at all in output. When either is jacked up to 7.0,
everything works and matches up; when either is set just a bit above the
default 5.0 (5.4 is what I was hoping to use), stems miss note heads. So
it's some sort of a numerical (truncation/roundoff) problem.
John
. * fix #'margin-shape;  setting indent to 0 with \shape fails
. * Fixed size staff/system heights;
. * ly2dvi : don't repeat opus if same. 
. * hara kiri _8 clef. 
. * junk -M ? 
. * mudela-book doco
. * fix or replace feta-accordion.mf
. * bracket pdf hack
. * Mondrup:
- if I change the property minVerticalAlign in a multi staff score with
lyrics the change affects the lyrics too. I would like the change to
_only_ affect staves.

- I would like to be able to influence the sloping of xtuplet brackets

- after the leading measure in the above mentioned score I want a double
bar line fully drawn across the staves and after that keep to the
ChoirStaff bar line types in the rest of the scores
. * Write script that uses --find-old-relative to do auto relativization. 


.* Cleanups needed
. * \$ and $ identifier syntax in examples. 
. * Key_engraver, Local_key_item
. * Think of comprehensive solution for "if (grace_b == self_grace_b_)"
. * String[String.length] doesn't trap.
. * Rhythmic_column and interaction stem/rhythmic_column/note_head/dots.
. * clef engraver 
. * parser
. * Lookup::text -> needs  to be TeX independent.
. * junk Music_iterator::first_b_

.* ACCIDENTALS
. * half-sharps, half-flats
. * adaptive accidental spacing.
. * accidentals closer to note head


.* BEAMS
. * [c8. c16 c16 c16] in 6/8 timesig.
. * Rewrite Stem, Beam (hairy)
.  * beams over barlines
. * Rests and beams don't work too well together. Example:
   [ r8 g''16 des'] [r8 c16 a] 
. * autoBeamMelisma: if I explicitly beam notes in a staff with auto
beaming disabled I would like to have these beams also to be
melismatic.
. * The stemLength property should affect also beamed stems.
. * staffside spanner (crescendo!) along with staffswitch.
. * * auto melismaBusy for beams.

. * 
> \context Staff <
>   {\voiceone''4. r8}
>  \voicetwo c,4 r4}
> >
. * sort out breve shapes.
. * \time forces keysig?

.* STUFF
. * We need feta-din*.mf files for more sizes than 10.
. * align left edge of broken tuplet-spanner (have a test case?)
. * fix dynamics decently, ie. use kerning & ligatures.
. * key restorations & repeats
. * paperXX.ly \quartwidth, font setting not up to date. (Should read from AFM?)
. *In Caro Mio Ben, bar 8, there's a syllable that starts on a note, and
ends on a pair of grace notes.  Standard practice is to mark this with
a slur starting on the main note and ending on the grace note, so a
singer knows where to break the words.

In bar 27, there's a crescendo that's supposed to start at the start
of the grace notes and extend to the note after the grace notes.
. * 4. Lyrics and grace sections don't go too well together.
 The words are aligned with the main note, not the start of the
 grace note.  This is usually wrong, but is sometimes right.
. * tie-direction
. * repeats and partial measures.
. * rhythmic staff & accidentals.
. * use melismaBusy in Lyric context to typeset melismata correctly.  
. * ly2dvi/lilypond logfile.
. * hang Item on Spanner
. * do --safe for PS output?
. * msgfmt -o check?
. * collision of lyrics with span_bars. See star-spangled.
. * It is impossible to typeset two textual scripts that are stacked
  on top of eachother and avoids note collisions and at the same
  time are typeset with different textStyle. I tried to move around
  the text_engraver and other engravers between Voice and Thread 
  but the granularity is not fine enough, the scripts have to 
  share the same engraver in order to be get correct vertical 
  position but than they cannot have different style.
  In my opinion, all scripts that share the same staff, should
  be stacked vertically, avoiding collisions with the notes
  in all voices.

. * Matanya's tips: 
.  * don't  shorten stems/staffs closer to each other.
.  * to space the staffs/staffgroups contained in the score.  
.  * heavier beams?

. * tuplets that are written as "number : note", for example
   "3 : [image of a half note here]".  possible?
. * a note with a circle after it, meaning:

   note + circle = note + 1/4 of its length

   the circle is like a dot that's not filled in.  for example, on
   page three, the c-sharp on the second line should be a quarter with 
   a circle, not a quarter tied to a sixteenth.  is this at all
   possible with lily?
. * make dependencies () a virtual function.
. * deprecate hangOnClef.
. * Abstraction for engravers:
.  * make "in-between" engraver (Tie)
.  * make wide_spanner_engraver (line_group_spanner, staff_symbol)
. * store req -> element, element -> element causes for warnings
. * compulsory hshift
. *  My wish list for lyrics. I dream of a time when I will have enough time to
become familiar enough with the source code to be able to implement some of
these myself, but I don't know when that will be, so I thought I'd "publish"
my suggestions in case someone else is in a position to give them some
priority. Otherwise, perhaps they could go on the todo list?

If any of these are already implemented, please let me what the syntax is to
use them!

1. Stanza numbering. Numbering at the beginning of a song with the number
set to the left of the first note. It would also be nice (but not as
important) to be able to have some form of automatic numbering at the
beginning of each new line. This would make it easier to follow songs with a
large number of stanzas.

3. Notes centred above/below lyrics rather than left-aligned.

4. It would be very nice to be able to build some kind of phrasing into the
lyrics of hymns, etc, so that the first words of a phrase are left aligned
with each other, the last words are right aligned, and the words in between
are centred.

5. In a song, with (say) four stanzas and a chorus, it would be nice to be
able to vertically align the chorus midway between the staves.

6. It would be nice to be able to put vertical brackets either side of a
repeated section with different words for each repeat.
. * Give # lines in linebreaking.  
. * arrows on slurs.
. * rewrite context defs using Scheme
. * junk TeX specifics from internal code.
. * \selectmusic to cut pieces from music. 
. * formatting of input stuff. 
.  * deps for ly2dvi
. * TODO: merge atom & molecule; make  tree from molecule.
. * Align_element::padding  ?
. * use streambufs and iostream
to provide IO handling for TeX stream, mudela stream, data-file.
. * seriously buffer TeX output (do profile of writing .5 mb TeX file.)
. * fix partial measures in meaningful way.
. * uniformise recent feta contributions.
.  * bigger and fatter 4/4 C
. * relative mode for midi2ly
. * junking \skip req in lyrics
. * midi2ly empty staffs.
. * use Fourier transformation for rhythmic quantisation.
. * horizontal centering of dynamics 
. * $DEPENDENCIES_OUTPUT support
. * turn slope-damping on/off
. * sort out directory stuff.
.  * --prefix option?
.  * -I option per filetype?
.  * kpathsea?
. * fix vertical alignment and stafflines
. * declaring Performers
. * text-items clash with stems/beams
. * --include, -I option for ly2dvi (pass on to lily)
. * fix placement of beam-less abbrev
. * \meter 3/4;
        <{\voiceone cis4. cis8 cis4 | cis4 cis cis | r1 }
         {\voicetwo cis,4 r r | r2. | r1 }> |
        }
. * Musical_pitch (analogous to Duration and Rhythmic_req)
          think about, analogous to pitch: 
           * { a4 a16 } c <-- duration of c?
           * < a4 b8 > c <-- duration of c?
. * \tempo 4. = 90;
. * make sure all ex's have a mudela-version
. * do rest-collisions for Multi_measure_rests as well.
. * split error/warning in error/warning/non_fatal_error
. * add a Duration_convert member to Duration_iter to set parameters.
        Junk global duration settings. 
.  * discourage breaking of slurs
. * fix variable define/lookup parser global<->paper
. * fix title/instrument placements; see input/test/title.ly
. * <\voiceone c4. \voicetwo c4>
. *  I'd like to change the \repetitions command to Jan's suggested
  syntax: \repeat "repeatsymbol" 2 {...}, but I'm not sure that
  I understand the implementation of repeats well enough.
. * add mudela-book-doc source to webstie.
. * fix singleStaffBracket
. * rename
.  * partial -> anacrouse
. * move paper vars into engraver properties
. * add new glyphs to font.ly
. * more intelligent file searching
. * disable spaces in TeX stuff
. * handle ^C for tmp/file creation.
. * make LilyPond RPM fully relocatable
. * better hshift (dots, distance, head dependent)
. * didot / big point.
. * clefs (AG): The "8" should appear closer to the actual clef,
touching it.
. * put errorlevel in Input class
. * junk nesting slurs


.* FONT
. * the bracket is ugly (wings are too parabolic, should be more circular)
. * versioning for Feta
. * rewrite dynamic signs.  They're kind of spaghetti now. 
. * The `3' in the meter key is a one or two pixels too thin (at 600dpi)
        in the middle:
. * design macro for penstroke with rounded endings
. * timesig C: fat yet less curved.  Check out relations. 
. * design decent macro for bulbed endings
. * printer dependencies.
. * versioning  
. * lo-res fixes.
. * work out sizes of character fonts.
. * more symbols
.  * piano pedals: Ped/*
.  * maxima notehead
.  * coda signs: Segno, O+
.  * glissando, arpeggio
.  * lengthened trill
. * include important spacing dims in fetalog 
. * scalability: use blot_diameter everywhere, make font chubbier for
    small sizes.

.* 3RD PARTY BUGS
. * UMR: Uninitialized memory read
      This is occurring while in:
            qst            [qsort.c]
            qsort          [libc.so.1]
            Keyword_table::Keyword_table(Keyword_ent*) [keyword.cc:28]
            My_lily_lexer::My_lily_lexer() [my-lily-lexer.cc:78]
            My_lily_parser::parse_file(String,String) [my-lily-parser.cc:54]
            do_one_file(String,String) [scores.cc:124]
      Reading 4 bytes from 0xefffeca8 on the stack.
      Address 0xefffeca8 is 728 bytes below frame pointer in function 
. *  Array<Axis [2] > axeses;

  for (int i=0; i < loose_elems.size (); i++)
    {
      Score_element* elt = loose_elems[i];
      /*
            with which axes do we have to meddle?
      */
      int j =0;
      Axis as [2];
      for (int a = X_AXIS; a < NO_AXES; ++a)
        if (elt->parent_l (Axis (a)) == this)
          as[j++] = Axis (a);
      if (j == 1)
        as[j++] = as[0];

      axeses.push (as);
    }

. * patch: don't touch timestamp if all patches fail.
. * MetaPost: should not generate setgray for unfill

. * mf-to-table -> add space 'before ; in AFM output.  (-> check AFM
spec. Is this a bug in afm2tfm?)
. * check out GCC signatures?
. * glibc 2.0:
          f = fopen ("/dev/null", "r")
          assert (feof (f))
. * tetex: mfplain.mem -> INSTALL
. * mfplain.ini not in tetex 0.9 -> INSTALL


.* PROJECTS
. * Scripts:
.  * stack scripts in chords:
          % fingering:        footing:
            < a-4 c-2 g-1 >   < c-\ltoe e-\lheel >
.  * script-spacing
.  * slur parts as a script
.  * stack parameterised scripts for fingering and footing:

. * convert-mudela:
.  * better parsing
.  * make smarter
.  * convert-mudela -e empty.ly

. * emacs mudela-mode
.  *  should handle block comments too.
.  *  handle lexer modes (\header, \melodic, \lyric) etc.
.  *  indentation
.  *  notenames?
.  *  fontlock: \melodic \melodic

. * use properties for:
.  * default tempo.

. * page handling:
.  * PS output
.  * optimal pagebreaking.

. * internationalisation for input.
.  * Unicode support? -> man 7 unicode
.  * (The explanation below is mostly intended for Han-Wen and Jan)
> Before, the font was changed with macros declared separately for 
> pure TeX and LaTeX, but now all the fonts are declared directly in
> the generated code using the low-level TeX commands. This circumvents
> the fontencoding mechanism of LaTeX and is a potential source of
> problems also for us users of the Latin-1 character set. 
> I think it still works since the inputencoding latin1 is 
> declared by ly2dvi, but it still means that e.g. an o with
> umlaut is typeset as a combination of the two symbols 'o' and
> 'umlaut' instead of as a single character, as would be the case
> if fontencoding OT1 had been used. This shouldn't give any 
> difference in layout, though. One of the main argument for using
> fontencoding OT1 is for the hyphenation mechanism to work, an 
> argument that's clearly irrelevant in our application. Yet we
> see the problem for August.

. * \header
.  * output header info to MIDI too.
.  * dump \header into easily parsable format.

. * a musical dictionary. See Documentation/vocabulary-*, other
languages:
.  * explanations
.  * italian
.  * german
.  * dutch
.  * swedish

. * chords
.  * guitar chords (fret diagrams)
.  * other chord name styles (american(?) style)
.  * basso continuo
.  * MIDI output?

. * Debug logs:
.  * derive lily_stream, Dstream, texstream from ostream?
.  * indentable stream as baseclass for TeX stream, lily stream, Dstream.
.  * use dstream feature in midi2ly
.  * integrate IO checking into stream class

. * input converters
.  * NIFF?
.  * musedata

. * add to MIDI output:
.  * sharp / flat on trills (in MIDI ??)
.  * ornaments (and trills?)
.  * slurs
.  * accents
.  * dynamics
> Would it be hard to add support for proper dynamics in MIDI output?  I
> would really like to have this feature...

Concretely spoken, for dynamics you have to write a performer
(Dynamics_performer), that will take the input requests. If I
understand correctly, every MIDI note played must have its dynamic
strength set separately.  That means the the Dynamics_performer must
set the strength of every Audio_note it finds.  This means that one
has to modify existing Audio items.  The best way of doing this is
with a broadcast/acknowledge process.

So the best way of handling this, is

  1 supporting dynamic settings in Audio_note

  2 Write a Dynamics_performer that will modify
  any notes it finds to set appropriate strengths.

I'd say that the work involved is not hard, but you have to be fluent
with C++ and need some insight into the working of Notation Contexts
and friends.  I guess I could do it in a day or so, but if you are not
so fluent with the inner workings of LilyPond, it could take you some
more time (A few more days?).

Please note, that I am *not* going to code this myself: my days are
valuable, and I think I have more interesting things to do than fixing
the MIDI output (I don't even have a soundcard).  But I *do* want to help
you or other people with implementing this, so if you need help, don't
hesitate to ask.
.  * account for rhythmic position in measure
.  * etc.


. * logfile output?

. * PS 
.  * speed up PS code.
.  * PS lines to .eps files
.  * write custom prolog
.  * fix ps font switching

. * more spanners (smallish)
.  * Glissando
.  * trill

. * Collisions
.  * left/right note balls should be handled by Collision:
        < \multi 2; { \stem 1; <b c> } { <f as b> } >

. * Keys:
.  * merge key{item} & localkey{item}?
.  * spacing

. * Support for TAB
.  * redo Notehead to allow digits as heads
.  * add a \tablature {} lexer mode for easy entering

. * should adjust stemlength for flag number.

. * breaking:
.  * specify number of lines

.* INPUTLANGUAGE
. * convention for slurs vs. phrasing marks.
. * Language:
.  * \translator -> ?
.  * fix \partial 
.  * \bla {} vs \bla ; 
.  * \once\property  KEY = VAL
.  * input property
. * Figure out semicolons.
. * <c f a>4 ?
. * configure pitch_byte
. * rest name configurable


.* SMALLISH PROJECTS

. * lyric in staff  (sharpsharp in staff, text below)

. * write Dynamic_line (to group dynamics horizontally)


. * handle EOF graciously in error messages.

. * midi esp.: use I32 iso int where 32 bits are needed (or assumed...)

. * lily \tempo

. *   % toe to bheel   four to five
            %   ^_u            4_5  
            %     -                           
            %  --|x--         --|x--
            %  --|---         --|---
            %  --|---         --|---
          (where "to" is a tiny bow)

. * auxilliary file for caching info.

. * Text_crescendo

.* IDEAS
. * Output data structures of Mudela in XML/SGML.
. * create libmudela, or liblily_frontend
. * move MIDI stuff (including Quantization) to a ANSI C libmidi library.

* OUTLINE SETUP
.* .EMACS
;;; from outline.el
(defvar outline-font-lock-keywords
  '(;; Highlight headings according to the level.
    ;; must change this to allout node layout
    ;;("^\\(\\*+\\)[ \t]*\\(.+\\)?[ \t]*$"
    ("^\\([.]*[ ]*[*]\\)[ \t]*\\(.*\\)$"
     (1 font-lock-string-face)
     (2 (let ((len (- (match-end 1) (match-beginning 1))))
          (or (cdr (assq len '((1 . font-lock-function-name-face)
                               (2 . font-lock-keyword-face)
                               (3 . font-lock-comment-face))))
              font-lock-variable-name-face))
        nil t))
    ;; Highlight citations of the form [1] and [Mar94].
    ("\\[\\([A-Z][A-Za-z]+\\)*[0-9]+\\]" . font-lock-type-face))
  "Additional expressions to highlight in Outline mode.")

(add-hook 'outline-mode-hook
          '(lambda ()
            (setq font-lock-maximum-decoration t)
            (setq font-lock-maximum-decoration t)
            (make-local-variable 'font-lock-defaults)
            (setq font-lock-defaults '(outline-font-lock-keywords t))
            (font-lock-mode global-font-lock-mode)
        ))
 
(require 'allout)
(outline-init 't)