When navigator is on the graphic update is very slow

• Mar 27, 2019 - 10:55
Reported version
S4 - Minor

Using Windows 7 on an i7 laptop, with version 3.0.5
1) Open or create a relatively long score (several pages)
2) Select Continuous view (in page view the problem is less severe)
2) Open navigator
3) Any attempt to drag the score lags or is sluggish


Frequency Many Once
Tags View Changes

Confirmed, navigator really seems to make a large difference in Continuous view.

"Frequency" refers mostly to a number of independent reports or mentions so I change that field to "once" for now.

Severity S4 - Minor S3 - Major
Reported version 3.5 3.6

I have also experienced this in 3.6. I would argue for higher Severity because the speed of Navigator updates affects any editing operation of the whole program. It can be pretty frustrating to edit notes when the score grows to a few hundred bars, unless the navigator window is closed.
Can navigator updates happen in a different thread? It won't matter if the view is a second or two behind, but interactive editing operations need to remain responsive.
Can layout recalculations be terminated early if the edit does not cause changes later in the document? i.e. if editing a note changes the length of a bar, this often won't affect the display any further ahead than the current stanza. Especially if there are explicit line breaks and page breaks later in the score.

Severity S3 - Major S4 - Minor
Type Graphical (UI) Performance
Workaround No Yes

We already have the code to do the partial layout, that's why editing can be fast when not using the navigator. So the question is, why doesn't the navigator do the same? Probably it should, but I'm not familiar with the navigator code.

Still, compared to other issues we identify as "major", this one is nowhere near as serious. The navigator isn't needed and probably used by only a small percentage of users (mostly ones who became accustomed to it many years ago when it was enabled by default), and remains unnecessary given all the other ways of navigating. And one can simply close it when not actively using it. So the workarounds are trivial.