Trill line playback always applies to voice 1
I'm not quite sure whether this would be called a bug report or a feature request; it feels like something unintended, but also something that can't be done with other line objects; a bit of both? Regardless, the problem is that trill lines from the line palette (and by extension wavy lines) apply their effects to a single voice in the measure. This is a problem in that you cannot actually set what voice the line modifies; it assumes voice 1 every time, and it takes no large effort to find an example that would contradict this. Sure, you could add a trill line, make it have no playback, then just add an invisible trill notation; but that's rather excessive considering that a trill line already functions for what we want it to do if it weren't for the voice restrictions.
Comments
I call it a bug :-)
To reproduce:
1) enter whole note "C" in voice 1
2) enter two half notes "A" in voice 2 (same measure)
3) attach trill to second half note "A"
4) play
Result: the "C" trills, not the second "A"
The trill itself lives in voice 1, which is probably the reason playback is off. Somehow the layout code doesn't seem to mind the line being in voice 1 even though it is attached to a note in voice 2, but they playback code isn't as happy. Not sure if we should consider actually putting the trill line into its proper voice or just make playback deal with it. Right now, there probably are assumptions in multiple places in the code that lines other than slurs live in voice 1.