Re: Proportional font display is corrupted after cursor moves away from them

[Jason Rumney]

address@hidden (Kim F. Storm) writes:

> In the scratch buffer, drag the mouse cursor from the middle of the
> first line to the third line, and back -- do that several times while
> holding down the mouse-1 button.  When I do that, the text on the
> second and third line moves one pixel to the left when highlighted,
> and back again when not highlighted.
>
> I don't know if those problems are related, but there is an
> off-by-one-pixel error somewhere.

The "off-by-one-pixel" error is called Cleartype (sub-pixel antialiasing).
In previous versions we disabled it, because we often ended up with
one pixel wide garbage when scrolling or editing, in the current
version we make sure we clip to the character's reported width to
avoid the one pixel error on some fonts. Whichever way we do it,
someone will complain.

> Another issue, when I move the mouse cursor side-ways over the toolbar,
> it flickers like crazy...

That's a real problem we should solve. There have been problems due to
excessive redrawing on Windows since 21.1. I've never been able to
figure out why it is redrawing more often on Windows.