Re: Mouse highlighting and fonts

[Chong Yidong]

Chong Yidong <address@hidden> writes:

> With the current CVS code, the mouse highlight preserves the size of the
> underlying face, which avoids the meta-stability problem I mentioned a
> few weeks ago.  However, mouse highlighting of the glyph background
> still doesn't work right when the underlying font size varies across the
> highlighted region.

BTW, another mouse-highlighting bug I reported earlier is still present.
Under certain circumstances, the area to the left and/or right of the
physical cursor doesn't acquire the proper mouse-face.

This appears to be a long-standing bug, but one that didn't show up
until the new font code.  That's because it arises as follows: when the
cursor glyph has a nonzero lbearing or rbearing (i.e., it overlaps with
its neighbors), the neighboring glyphs are redrawn, and this can
overwrite the mouse-face highlight.  See xdisp.c:19934.  This didn't
show up because previously, overlapping glyphs were generally not
encountered.

I'll try to fix this once I get the time, unless someone else fixes it
first.