lyrics align is wrong on lyrics containing numbers and space

• Dec 10, 2018 - 09:31
Reported version
P1 - High
S2 - Critical

Lyrics with lyrics dash or melisma are getting left aligned to the notehead's left border.
Licurs with a (stanza) number (e.g. "1. While") are supposed to get left alinged so the 1st 'real' lyrics character is left aligned to the left border of the note head and are in 2.x
In 3.0 however they seem to align to that space, so are off by some 0.5sp


Workaround is to tweak the x-offset in Inspector. That does only work for odd lyrics though, see #279774: x-offsets applied to even lyrics lines don't stick (don't survice save/close/open)

Attachment Size
lyricvs-align.mscz 3.27 KB


But MuseScore 2.3.2 seems to do the same. Here is the screenshot:
Space bar seems to be not so wide but otherwise the result looks similar.

the difference is subtle, in 2.3.2 the left edge of the 1st letter after the space seems aligned to the left edge of the notehead, in 3.0 the left edge of the 1st letter after the space seems aligned to the center of the note head.
So a 0.5sp difference.
Not the case with melisma and lyrics dash, there it is left aligned, just like it should.
Possibly that this is due to a wider space.

Priority P0 - Critical P1 - High

Subtle but present. I suspect most people will live with it, but we do want to correct this soon to avoid people making manual adjustments that need to be revisited later.

Eventually I found that lyrics layout indeed does an attempt to adjust lyrics position according to the leading part width. However this width seems to be calculated not accurately as the calculation does not consider that the width of the given chunk of text may depend on which characters are placed next to the given part of the text line. At least whitespace seems to be wider when being in the middle of the line rather than in the end of the line. I tried to correct these calculations (this commit) and got something like this:

However this will probably work only for the case if font does not change during the lyrics syllable. This makes this issue somewhat related to #279376: Inconsistent underlining of tempo text: we seem to need a way to correctly calculate dimensions of any parts of text elements based on TextBase in order to be able to align them all correctly.

The original code to calculate the amount of "leading" space was kind of a hack, a compromise based on a series of discussions about what should be ignored and what shouldn't. Meanwhile, the treatment of verse numbers themselves also changed a couple of times - they were separate elements for a while, etc. Eventually we should probably really revisit this whole algorithm.

How about this?

diff --git a/libmscore/lyrics.cpp b/libmscore/lyrics.cpp
index 8df2d27f7..7bf3b8584 100644
--- a/libmscore/lyrics.cpp
+++ b/libmscore/lyrics.cpp
@@ -261,8 +261,8 @@ void Lyrics::layout()
                         Lyrics trailing(*this);
-                        leftAdjust = leading.width();
-                        centerAdjust = leading.width() - trailing.width();
+                        leftAdjust = leading.width() + symWidth(SymId::noteheadBlack) * 0.5;
+                        centerAdjust = leftAdjust - trailing.width();
                         if (!lp.isEmpty() && lp[0].isDigit())
                               hasNumber = true;

With that the above example looks the same as it did MuseScore 2.

I haven't gone through in detail, but that indeed looks like the right sort of adjustment to make, so if it works I'd say you got it! Did you try both melisma and non-melisma syllables, to catch both the left & center cases?

Status PR created fixed

Fixed in branch master, commit e129be0137

_fix #279770: fix aligning of lyrics with leading/trailing numbers

The previously used method did not take into account the fact that
width of some characters (e.g. whitespaces) may vary depending on
the surrounding context. This commit corrects leading/trailing parts
widths calculation by making use of TextBlock::xpos() function which
is used also for text cursor placement in text editing mode._

Fix version