@c -*-texinfo-*- @node Introduction @chapter Introduction LilyPond is a program to print sheet music. If you have used notation programs before, then the way to use this program might be surprising at first sight: in order to print music you have to enter musical codes in a file. Then you run the program on the file, and the music is produced without any further intervention. For example, something like this: @lilypond[fragment,verbatim, relative 1, intertext="produces this: "] \key c \minor r8 c16 b c8 g as c16 b c8 d | g,4 @end lilypond @cindex encoding music Encoding music using letters and digits may appear strange, intimidating or even clumsy at first. Nevertheless, when you take the effort to learn the codes and the program you will find that it is easier than it seems. Entering music can be done quickly, and you never have to remember how you made the program do something complicated: it is all in the input code, and you only have to read the file to see how it works. Moreover, you are rewarded with very nicely looking output. In this chapter, we will explain the reasoning behind this unusual design, and how this approach affects you as a user. @menu * Batch processing:: * Music engraving:: * Music representation:: * Example applications:: * About this manual:: @end menu @node Batch processing @section Batch processing @cindex GUI @cindex Batch @cindex UNIX When we started developing LilyPond, we were still studying at the university. We were interested in music notation, not as publishers or musicians, but as programmers and scientists. We wanted to figure to what extent formatting sheet music could be automated. Back then GUIs were not as ubiquitous as they are today, and we were immersed in the UNIX operating system, where it is very common to use compilers to achieve computing tasks. So, our computerized music engraving experiment took on the form of a compiler. @ignore @cindex free software @cindex sharing software You can freely use, modify and redistribute LilyPond. This choice was also motivated by our academic background. In the scientific community it has always been a tradition to share knowledge, also if that knowledge was packaged as software. One of the most visible groups that stimulated this philosophy, was the Free Software Foundation, whose popular GNU project aimed to replace closed and proprietary computing solutions with free (as in ``Libre'') variants. We jumped on that bandwagon, and released LilyPond as free software. That is the reason that you can get LilyPond at no cost and without any strings attached. @end ignore @node Music engraving @section Music engraving @cindex engraving @cindex typography Making sheet music may seem trivial at first (``you print 5 lines, and then put in the notes at different heights''), @emph{music engraving}, i.e. professional music typography, is in another ballpark. The term `music engraving' derives from the traditional process of music printing. Only a few decades ago, sheet music was made by cutting and stamping the music into zinc or pewter plates, mirrored. The plate would be inked, and the depressions caused by the cutting and stamping would hold ink. A positive image was formed by pressing paper to the plate. Stamping and cutting was completely done by hand. Making corrections was cumbersome, so engraving had to be done correctly in one go. As you can imagine this was a highly specialized skill, much more so than the traditional process of printing books. @cindex craftsmanship @cindex master In the traditional German craftsmanship six years of full-time training, more than any other craft, were required before a student could call himself a master of the art. After that many more years of practical experience were needed to become an established music engraver. Even today, with the use of high-speed computers and advanced software, music requires lots of manual fine tuning before it acceptable to be published. When we wanted to write a computer program to do create music typography, we encountered the first problem: there were no sets of musical symbols available: either they were not available freely, or they did not look well to our taste. Not let down, we decided to try font design ourselves. We created a font of musical symbols, relying on nice printouts of hand-engraved music. The experience helped develop a typographical taste, and it made us appreciate subtle design details. Without that experience, we would not have realized how ugly the fonts were that we admired at first. @lilypond[noindent] #(define magfact 3.0) \score { \notes { as'2 r4 } \paper { raggedright = ##t \translator { \ScoreContext AccidentalPlacement \override #'right-padding = #3.0 StaffSymbol \override #'transparent = ##t Clef \override #'transparent = ##t TimeSignature \override #'transparent = ##t Accidental \override #'font-magnification = #magfact Rest \override #'font-magnification = #magfact NoteHead \override #'font-magnification = #magfact Stem \override #'transparent = ##t } } } @end lilypond @cindex musical symbols @cindex font @cindex blackness @cindex balance The figure above shows a few notable glyphs. For example, the vertical stem of a flat symbol should be slightly brushed, i.e. becoming wider at the top. the half-notehead is not elliptic but slightly diamond shaped. Fine endings, such as the one on the bottom of the quarter rest, should not end in sharp points, but rather in rounded shapes. Taken together, the blackness of the font must be carefully tuned together with the thickness of lines, beams and slurs to give a strong yet balanced overall impression. Producing a strong and balanced look is the real challenge of music engraving. It is a recurring theme with many variations. In spacing, the balance is in a distribution that reflects the character of the music. The spacing should not lead to unnatural clusters of black and big gaps with white space. The distances between notes should reflect the durations between notes, but adhering with mathematical precision to the duration will lead to a poor result. Shown here is an example of a motive, printed twice. It is printed using both exact mathematical spacing, and with some corrections. Can you spot which is which? @cindex optical spacing @lilypond[noindent] \score { \notes { \property Staff.NoteSpacing \set #'stem-spacing-correction = #0.6 c'4 e''4 e'4 b'4 | \stemDown b'4 e''4 a'4 e''4| \stemBoth \property Staff.NoteSpacing \override #'stem-spacing-correction = #0.0 \property Staff.StaffSpacing \override #'stem-spacing-correction = #0.0 c'4 e''4 e'4 b'4 | \stemDown b'4 e''4 a'4 e''4| } \paper { raggedright = ##t } } @end lilypond @cindex regular rhythms @cindex regular spacing The fragment that was printed uses only quarter notes: notes that are played in a constant rhythm. The spacing should reflect that. Unfortunately, the eye deceives us a little: the eye not only notices the distance between note heads, but also between consecutive stems. As a result, the notes of a up-stem/down-stem combination should be put farther apart, and the notes of a down-up combination should be put closer together, all depending on the combined vertical positions of the notes. The first two measures are printed with this correction, the last two measures without. The notes in the last two measures form downstem/upstems clumps of notes. We hope that these examples show that music typography is a subtle business, and that it requires skill and knowledge to produce good engraving. It was our challenge to see if we could put such knowledge into a computer program. @node Music representation @section Music representation One of the big questions when making programs, is what kind of input the program should expect. Many music notation programs offer a graphical interface that shows notation, and allow you to enter the music by placing notes on a staff. From our point of view, this design is a form of cheating. After all, the core message of a piece of music notation simply is the music itself. If you start by offering notation to the user, you have already skipped one conversion, even if it is implicit. If we want to generate music notation from something else, then the obvious candidate for the source is the music itself. On paper this theory sounds very good. In practice, it opens a can of worms. What really @emph{is} music? Many philosophical treatises must have been written on the subject. Instead of losing ourselves in philosophical arguments over the essence of music, we have reversed the question to yield a more practical approach. Our assumption is that the printed score contains all of the music of piece. We build a program that uses some input format to produce such a score. Over the course of time, the program evolves. While this happens, we can remove more and more elements of the input format: as the program improves, it can fill in irrelevant details of the input by itself. At some (hypothetical) point, the program is finished: there is no possibility to remove any more elements from the syntax. What we have left is by definition exactly the musical meaning of the score. There are also more practical concerns. Our users have to key in the music into the file directly, so the input format should have a friendly syntax. As programmers and scientists, we want a clean formal definition. After all, producing music notation is a difficult problem, and in the scientific world, problems can only be solved if they are well-specified. Moreover, formally defined formats are easier to write programs for. These ideas shaped our music representation: it is a compact format that can easily be typed by hand. It complex musical constructs from simple entities like notes and rests, in much the same way that one builds complex formulas from simple expressions such as numbers and mathematical operators. @node Example applications @section Example applications As programmers and hedonists we enjoy beauty in code, and code that produces beautiful typeset music, but nevertheless this program can applied to do useful things. In this section, we show a few small examples of what is possible. The simplest application, is printing just notes. @lilypond[relative=1] \time 2/4 c4 c g'4 g a4 a g2 @end lilypond To these notes, chord names and lyrics may be added @lilypond[raggedright] \score { < \context ChordNames \chords { c2 c f2 c } \notes \relative c' { \time 2/4 c4 c g'4 g a4 a g2 } \context Lyrics \lyrics { twin kle twin kle lit tle star } > } @end lilypond [TODO: need piano and tab example] The following example combines some more exotic uses of notation @lilypondfile{screech-boink.ly} @node About this manual @section About this manual The manual is divided into the following chapters @itemize @bullet @item The @emph{tutorial} (@ref{Tutorial}) gives a gentle introduction into typesetting music. First time users should start here. @item The @emph{notation manual} (@ref{Notation manual}), is a user manual that discusses topics grouped by notation construct. @item The @emph{technical manual} (@ref{Advanced topics}) discusses the general design of the program, and how to extend the functionality. @item The chapter on @emph{Invoking} (@ref{Invoking LilyPond}) explains how to run LilyPond and its helper programs. @end itemize Once you are experienced, you can simply use the manual as reference: there is an extensive index@footnote{If you are looking for something, and you cannot find it by using the index, that is considered a bug. In that case, please file a bug report}, but the document is also available in @ifnothtml One Big Page, @end ifnothtml @ifhtml @uref{One Big Page,../lilypond.html} @end ifhtml which is is available for text search using your browser's search facility. @cindex search in manual @cindex using the manual If you are familiar with music notation, and music terminology (especially if you are a foreigner), then it is advisable to consult the glossary as well. This documents explains many terms, and includes translations to various languages. It is a @ifhtml @uref{../glossary.html,separate document} @end ifhtml @ifnothtml separate document, and can be printed as well. @end ifnothtml @cindex idiom @cindex jargon @cindex terminology @cindex foreign languages @cindex language This manual is not complete without a number of other documents. They are not available in print, but should be included with the documentation package for your platform @itemize @bullet @item Generated internal documentation. @ifhtml available @uref{../lilypond-internals/lilypond-internals.html,here} @end ifhtml Almost all formatting functionality that is used internally, is available directly to the user. For example, all variables that control thicknesses, distances, etc, can be changed in input files. There are a huge number of formatting options, and it would be impossible to describe them all in a hand-written manual. The generated internal documentation is a heavily crosslinked HTML document, produced directly from the formatting definitions used. It documents the nit-gritty details of each and every LilyPond class, object and function. Each section of the reference manual has a @b{See also} subsection, with links (in the HTML document, at least) to the generated documentation. @item Templates @ifhtml (available @uref{../../../input/templates/out-www/collated-files.html,here}) @end ifhtml When you have gone through the tutorial, you theoretically should be able to start writing input files. However, this turns out to be a little intimidating. To give you a headstart, we have collected a number of often-used formats in example files. You can take one of these example files, and add notes in the appropriate places to generate output. @item Various input examples @ifhtml available @uref{../../../input/test/out-www/collated-files.html,here} @end ifhtml @cindex snippets These small files show various applications of lilypond, and are available as a big HTML document, with pictures and explanatory texts included. @item The regression test @ifhtml available @uref{../../../input/regression/out-www/collated-files.html,here} @end ifhtml We strive to test each feature in one test file. This collection of is primarily to help us debug problems, but it can be instructive to see how we excercise the program. The format is like the input examples. @end itemize The location of the documentation files that are mentioned here can vary from system to system. Throughout this manual, we refer to input files relative to the top-directory of the source archive. For example, @file{input/test/bla.ly} may refer to the file @file{lilypond-1.7.19/input/test/bla.ly}. On binary packages for the Unix platform, these can typically be found somewhere below @file{/usr/share/doc/lilypond/}. Initialization files, for example @file{scm/lily.scm}, or @file{ly/engraver-init.ly}, are usually found in the directory @file{/usr/share/lilypond/}. @cindex adjusting output @cindex variables @cindex properties @cindex lilypond-internals @cindex internal documentation @cindex Scheme @cindex extending lilypond @cindex bugreport @cindex index