Support more music notation

[cecilios]

Currently Lomse does not support a large number of elements of musical notation, only the most common. But supporting a new element requires to add it in several places:

• To the LDP language (the source language that is used for representing scores is specific for LenMus and developed as part of the project).
• To the algorithms for layouting scores (that is, the algorithms for deciding what symbols to use for each musical element of a source file and where to position them on the screen to create a picture of the score).
• To related areas: LDP compiler, LDP exporter, internal model, graphic model).

Engraving is a very complex area, which has many problems and lends itself to many research papers and dissertations. It is an area of work for a student or graduate student who want to get started on doing research and publishing articles. LenMus software provides a very good code base for someone who wants to use it as a starting point.

It is necessary to contine advancing by adding support for more elements:

• full measure rests (i.e. MozartTrio.xml: measure 7, first instr.) (issue #8):

        <rest measure="yes"/>
        <duration>18</duration>

• Multi-measure rests
• All MusicXML accidentals
• more note types, maxima, 512th, 1024th --> Moved to issue #29
• repetition brackets (Saltarello.xml, ) --> Moved to issue #79
• other barline types: dashed, dotted, heavy, heavy-heavy, tick, short, (none?) (46a-Barlines.xml, Chant.xml)
• more key signatures and non-standard key signatures
• grace and cue notes
• editorial and cautionary acccidentals in notes
• groups of instruments. Done PR#47 & PR#49
• More MIDI information in instruments: volume, pan. Done PR#86
• Titles and meta-information in scores
• Compound time signatures
• lyrics. Commit 27301ae added support for lyrics, but need to improve spacing algorithm PR#222 fixes this
• dynamic marks. Done

[cecilios]

Closing this as it it is not updated (most of the items in the list are now supported) and it is too generic. If necessary, please open a new issue for each specific required notation.