Re: master 77c3d41adc: Prevent text decorations from overwriting surrounding areas on X

[Po Lu]

Po Lu via Mailing list for Emacs changes <emacs-diffs@gnu.org> writes:

>     Prevent text decorations from overwriting surrounding areas on X
>     
>     * src/xterm.c (x_draw_underwave): New parameter
>     `decoration_width'.
>     (x_draw_glyph_string): Constrain decoration width to current
>     text area.

This happens on X because nothing actually clips the decoration to the
string's area when we draw the decoration.

You can test by running custom-set-faces on default, enabling an
underline or overline, and typing in a field that is extended to the end
of the line.

It doesn't happen on NS or Haiku -- but I have no idea if a similar
adjustment is needed on MS-Windows.