Re: Color fonts
Behdad Esfahbod <[email protected]>
| Newsgroups | gmane.comp.lib.cairo,gmane.comp.gnome.gtk+.devel.general |
|---|---|
| Message-ID | <CAF63+7W8tWr6X_u3e9S-SViaZv7nkV9om97f93UrpQASJLeLzA@mail.gmail.com> |
Right. In the future we would want to make it show glyphs in the input order, ie. not separate color vs non-color. That's the order required by CSS for example. In a show-text-glyphs call with CAIRO_TEXT_CLUSTER_FLAG_BACKWARD, it might be desirable to show back-to-front. On Tue, Jul 18, 2017 at 1:59 PM, Matthias Clasen <[email protected]> wrote: > On Sat, Jul 15, 2017 at 4:05 AM, Uli Schlachter <[email protected]> wrote: > >> On 07.07.2017 15:23, Matthias Clasen wrote: >> > On Sat, Jul 1, 2017 at 2:25 AM, Uli Schlachter <[email protected]> wrote: >> >> On 30.06.2017 17:29, Behdad Esfahbod wrote: >> >>> On Jun 30, 2017 7:51 PM, "Matthias Clasen" <[email protected]> >> wrote: >> >>> On Fri, 2017-06-30 at 17:02 +0200, Uli Schlachter wrote: >> >>>> On 28.06.2017 14:23, Behdad Esfahbod wrote: >> >>>>> All of you have asked me about the status of color fonts in >> >>>>> cairo. There's >> >>>>> some discussion here: >> >>>> >> >>>> what was the solution to make this fit into cairo's drawing model? >> >>>> Text >> >>>> / glyphs are used as a mask and a mask does not have colors. >> >>>> >> >>> >> >>> There is no solution to that. The assumption in cairo's drawing model >> >>> about glyphs/fonts has simply been invalidated by reality. >> >>> >> >>> >> >>> Correct. >> >> >> >> Okay... so what is the new model? What happens when I draw a color >> glyph >> >> with operator XOR and a red source? >> > >> > >> > The red source is ignored for color glyphs because they are used as the >> > source. >> >> Hi again, >> >> I just came up with another question: How are overlapping glyphs handled? >> >> Let's say I have a red glyph and a blue glyph and I draw them in such a >> way that they overlap. Let's say this additionally overlaps with a >> non-colored glyph in the same position and I use a green source with 50% >> alpha (cairo_set_source_rgba(cr, 0, 1, 0, 0.5)). >> >> What's the visible result? >> >> > Here is what my implementation does: It renders the color glyphs, in > order, followed by the non-color glyphs. > > In practice, I don't think the case of mixed color and non-color glyphs in > the same call will be all that common. > Most apps will explicitly set a color font just for the emoji and they > won't render regular text with an emoji font, > with the result that runs of color glyphs and non-color glyphs will > typically be in separate calls. > -- behdad http://behdad.org/ -- cairo mailing list [email protected] https://lists.cairographics.org/mailman/listinfo/cairo