XML import/export

[j-bresson]

Todo:

• import
• export
• Menus in score editors

[j-bresson]

MusicXML Import done and commited in: c6fa2e9

[j-bresson]

Notes about MusicXML export

Most of the code is already there (in musicxml-export.lisp) but needs some cleanup and rewriting (and testing!).

In particular: the whole duration/subdivision system (e.g. for groups, beams, etc.) needs to be rewritten. There is no more extent/qvalue in OM# musical objects: in principle this is all more "flat" and simple, with the slots "symbolic-date" and "symbolic-dur" that are bound to chords and rests according to the tree at initializing/updating the voice.
The resulting code for export-musicxml should be much simpler / more readable than the current one.

[j-bresson]

Related threads:

• https://discussion.forum.ircam.fr/t/exporting-musicxml/20728/19
• Export MusicXML and CHORD-SEQ rhythm Segmentation/Quantization  om-sharp-users#19
• Export score to bach om-sharp-users#65

[smoge]

https://github.com/cac-t-u-s/om-sharp/issues/352

[j-bresson]

@smoge moving your comment and pointer here:

For reference, if the module is the same one from openmusic, this discussion is relevant, and points out some problems that need attention (for example: dorico supports musixml 3+, and some applications have problems with rationals, that would need to be checked again today)
https://discussion.forum.ircam.fr/t/xml-and-dorico/2449/3

[smoge]

Thanks. I think there is no point in "disputing" the correct implementation.

Since musicxml is a bad standard, one must be pragmatic. I think we should avoid using rational numbers, this way we avoid some problems. And also, it would be important to adopt the musicxml3 or musicxml4 standard, for dorico compatibility. I believe nested tuplets just works on musescore and dorico:

<measure number="23">
   <note>
      <pitch>
         <step>C</step>
         <octave>5</octave>
      </pitch>
      <duration>24</duration>
      <voice>1</voice>
      <type>quarter</type>
      <time-modification>
         <actual-notes>3</actual-notes>
         <normal-notes>2</normal-notes>
      </time-modification>
      <stem default-y="-50">down</stem>
      <notations>
         <tuplet bracket="yes" number="1" placement="above" type="start"/>
      </notations>
   </note>
   <note>
      <pitch>
         <step>B</step>
         <octave>4</octave>
      </pitch>
      <duration>24</duration>
      <voice>1</voice>
      <type>quarter</type>
      <time-modification>
         <actual-notes>3</actual-notes>
         <normal-notes>2</normal-notes>
      </time-modification>
      <stem default-y="-55">down</stem>
   </note>
   <note>
      <pitch>
         <step>A</step>
         <octave>4</octave>
      </pitch>
      <duration>8</duration>
      <voice>1</voice>
      <type>eighth</type>
      <time-modification>
         <actual-notes>9</actual-notes>
         <normal-notes>4</normal-notes>
         <normal-type>quarter</normal-type>
      </time-modification>
      <stem default-y="10">up</stem>
      <beam number="1">begin</beam>
      <notations>
         <tuplet number="2" bracket="no" placement="above" type="start">
            <tuplet-actual>
               <tuplet-number>3</tuplet-number>
               <tuplet-type>eighth</tuplet-type>
            </tuplet-actual>
            <tuplet-normal>
               <tuplet-number>1</tuplet-number>
               <tuplet-type>quarter</tuplet-type>
            </tuplet-normal>
         </tuplet>
      </notations>
   </note>
   <note>
      <pitch>
         <step>G</step>
         <octave>4</octave>
      </pitch>
      <duration>8</duration>
      <voice>1</voice>
      <type>eighth</type>
      <time-modification>
         <actual-notes>9</actual-notes>
         <normal-notes>4</normal-notes>
         <normal-type>quarter</normal-type>
      </time-modification>
      <stem default-y="8">up</stem>
      <beam number="1">continue</beam>
   </note>
   <note>
      <pitch>
         <step>F</step>
         <octave>4</octave>
      </pitch>
      <duration>8</duration>
      <voice>1</voice>
      <type>eighth</type>
      <time-modification>
         <actual-notes>9</actual-notes>
         <normal-notes>4</normal-notes>
         <normal-type>quarter</normal-type>
      </time-modification>
      <stem default-y="5">up</stem>
      <beam number="1">end</beam>
      <notations>
         <tuplet number="1" type="stop"/>
         <tuplet number="2" type="stop"/>
      </notations>
   </note>
</measure>