Linebreak algorithm

[barbeque-squared]

In #26 I noted that the specific beats at which line breaks occured are (at the time of writing) ignored by the parser. Currently, the song format files have line breaks at specific beats, but other than saving some computation work, is it really that useful? It's probably not hard to add a little algorithm that, given two sentences A and B, computes the optimal line break beat.

Here's some pseudo algorithm, I've explicitly used the notes for start/endbeat here, there's a convenience method on the Sentence object as well which will do just that (the important thing to remember is that a Sentence doesn't have any "padding"):

• If (A.lastnote.endbeat >= B.firstnote.startbeat) return A.lastnote.endbeat
  (we can't really do anything useful in this situation)
• Else:
  • compute the midway (or 2/3 or something else) point between A.lastnote.endbeat and B.firstnote.startbeat, call it C for now. I checked some random songs and most seem to have it at around 60%
  • compute some A.lastnote.endbeat + (x seconds * BPM) and call it D for now. One second is probably fine.
  • If C < D ? return C : return D

Essentially, this will cause two equidistant sentences to always have the same (relative) linebreak beat.

[barbeque-squared]

This can probably be implemented the easiest in the MutableVoice.AddSentence function, by changing the List<Sentence> to List<MutableSentence> so that we can easily change the start of the current sentence and end of the previous sentence when a new one is added?

[basisbit]

linebreak timings are there for a reason. Sometimes you want a linebreak to happen very late, so the next line is a bit more of a surprise and other times - especially in more fast paced songs, you'll want the line breaks to happen earlier, so one still has enough time to read ahead.
I'd suggest for those files where linebreaks are earlier or later than the previous / next note, your suggested linebreak algorithm should be used whenever the txt file's linebreak information is trash..

[basisbit]

fyi, if you press t in the USDX editor and then press s to save, it will adjust all linebreaks to be two third between the first and last notes, if possible.

[barbeque-squared]

didn't know about the 't' in the editor, but after playing around with it for a bit, I find that setting them myself works just fine.
I'm also closing this because after some discussion, we decided that people should just fix their txt's instead of us trying to do it for them. The current state of the branch will reject invalid txt's, even if they could be 'fixed' by this feature request.