Glyph editor window: add a visual alignment indicator

Nobody has claimed this yet.

When a single point is selected and I'm moving it around with the arrow keys, I usually want visual feedback to see when other points are aligned with the selected point (have the same x or y position). Without this feature a lot of time is spent changing which point is selected and looking at the x/y position at the bottom of the window.

Other font editors will show a temporary alignment indicator that goes away after a few seconds.

For less geometric drawing styles, some people might want to turn this kind of feature off, since knowing when points are aligned can lead to less optically oriented decision making.


Start by locating the glyph editor's single-point selection and arrow-key movement entry points, then inspect how the selected point's x/y position is shown at the bottom of the window. Done means aligned points receive a temporary visual indicator during movement, the indicator disappears after a few seconds, and users can disable it.

Written by the indexing model from the issue text.