A technical support community for Apple Logic Pro users.

 
Lars L
Topic Author
Posts: 10
Joined: Mon May 03, 2021 2:43 am

Bug: Auto-slurs merged into single slur when exporting to MusicXML

Tue May 04, 2021 3:21 am

Version: Logic Pro 10.6.2
OS: macOS 10.15.7
Computer: MacBook Pro Retina, 15 inch, late 2013

Description:
Exporting a score to MusicXML will not correctly preserve all auto-slurs. When there are consecutive auto-slurs in the same region, without any notes inbetween the slurs, exporting to MusicXML will merge together the slurs into a single slur, spanning from the beginning of the first auto-slur to the end of the last auto-slur.

Steps to reproduce:
  1. Create a software instrument and a MIDI region in it.
  2. Add four notes in the piano roll or score editor, for example C3, D3, E3, F3 on successive beats (filling each beat). The specific notes or note lengths should not matter, however.
    Before adding auto-slur.png
    Before adding auto-slur.png (13.11 KiB) Viewed 720 times
  3. In the score editor, add an auto-slur between C3–D3 and an auto-slur between E3–F4.
    After adding auto-slur.png
    After adding auto-slur.png (14.02 KiB) Viewed 720 times
  4. Export to MusicXML.

Expected behavior:
The exported MusicXML file should preserve the slurs between C3–D3 and E3–F3, so that there are two slurs in the exported file.

Actual behavior:
The exported MusicXML file has merged the slurs together into a single slur, between C3–F3. Importing the file into Logic or another note editor will therefore not preserve the original slurs. Result after importing:
After importing.png
After importing.png (12.66 KiB) Viewed 720 times

Technical details:
Inspecting the MusicXML file shows that the error lies in the export from Logic. The file contains the following data for the notes:
<note>
   <pitch>
      <step>C</step>
      <octave>4</octave>
   </pitch>
   <duration>1</duration>
   <voice>1</voice>
   <type>quarter</type>
   <stem>up</stem>
   <staff>1</staff>
   <notations>
      <slur number="1" type="start"/>
   </notations>
</note>
<note>
   <pitch>
      <step>D</step>
      <octave>4</octave>
   </pitch>
   <duration>1</duration>
   <voice>1</voice>
   <type>quarter</type>
   <stem>up</stem>
   <staff>1</staff>
</note>
<note>
   <pitch>
      <step>E</step>
      <octave>4</octave>
   </pitch>
   <duration>1</duration>
   <voice>1</voice>
   <type>quarter</type>
   <stem>up</stem>
   <staff>1</staff>
</note>
<note>
   <pitch>
      <step>F</step>
      <octave>4</octave>
   </pitch>
   <duration>1</duration>
   <voice>1</voice>
   <type>quarter</type>
   <stem>up</stem>
   <staff>1</staff>
   <notations>
      <slur number="1" type="stop"/>
   </notations>
</note>

Only the first and last note contain <slur> elements. These elements should be present in each note, with proper start/stop pairs according to the score.

Workarounds:
Change the slurs from auto-slurs to manual slurs. Consecutive manual slurs are preserved correctly when exporting to MusicXML.