I’ve found with the latest development branch of pyqtgraph (well, latest as of sometime last week at least) that it is rather difficult to position the mouse properly to move a PolyLineROI. What it looks like is if the cursor is at all close to any of the lines, only the line it is closest to get selected, rather than the entire ROI (as would be needed to move the ROI).
In digging into this, I found I could “fix" the behavior by removing the entire hoverEvent() method from the _PolyLineSegment class, but I’m sure this isn’t the right fix - it was just quick and dirty.
I don’t recall having issues like this with an earlier version of PyQtGraph, however, so perhaps this is something that has changed in the last few months?
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Israel Brewster
Software Engineer
Alaska Volcano Observatory
Geophysical Institute - UAF
2156 Koyukuk Drive
Fairbanks AK 99775-7320