Re: Stipples and scroll optimizations

[Po Lu]

Eli Zaretskii <eliz@gnu.org> writes:

> I think doing this is x_draw_glyph_string is too late, because that is
> called after the test for applicability of scrolling_window was
> already done, no?

I meant to do the test beforehand, i.e. to the glyphs in the "previous"
glyph matrix, and to use its results when comparing that matrix to the
desired matrix in scrolling_window.

> Is the fact that some of the glyphs in a glyph-row use stipple easily
> detectable by scanning the row's glyphs?  If so, update_window could
> do that, just before it calls scrolling_window, and refrain from doing
> so.

No, whether or not a stipple is actually used is only known with
complete certainty to x_draw_glyph_string (and some of the functions
that it calls.)