elm-abc2vextab

WORK IN PROGRESS

This is an Elm 0.18 utility which translates an AbcTune (defined in Abc.ParseTree) into VexTab and hence allows scores to be produced from ABC tunes.

VexTab is a pre-alpha release. There are various features of a score which almost any self-respecting tune will require but which currently remain unsupported. These include:

• First and second repeats
• Slurs (it seems as if these are supported in VexFlow but not yet available in VexTab syntax. The closest approach appears to be a bend which only associates two adjacent notes)
• Grace notes

There are some required features where it is unclear whether or not VexTab supports them:

• Changing time signature, key, clef mid-stave
• Textual attributes of the complete tune (title, tempo, composer etc.)

There are also some outstanding VexTab bugs which continue to bite us

• Quadruplets in triple time do not display properly. It looks to me as if tuplets in general only display properly in common time.
• No option to set a time signature 'quietly' so that it doesn't display in the stave but still takes effect (in order to drive auto-beaming etc.)

examples

scoreEditor.html is an interactive editor for ABC scores. As each edit is made to the ABC, then, (assuming it is valid), the amended score is displayed. It is built from ScoreEditor.elm. To build, cd to the examples directory and invoke compilee.sh.

abc2ScoreDebugger.html allows you to enter ABC text and then attempt to render it as a score by clicking on the render button. The intermediate VexTab text is also displayed, as are any error messages. It is built from Abc2ScoreDebugger.elm. To build, cd to the examples directory and invoke compiled.sh.

Progress

done

• staves - key signature, meter, (treble) clef
• modal keys
• bar lines
• notes
• tuplets
• rests
• basic chords
• broken rhythm pairs
• ties
• headers between stave lines
• Decorations (up and down bow, staccato, accent, fermata)

next things to do

• Inline headers - are they supported by VexTab?
• What happens if the tune has very low notes? How to detect a bass clef?
• Further decorations?

notes

• Although unsupported in VexTab, first and second repeats are 'hacked' using text decorations.