Re: Directional Images

You're right, drop shadows don't work well when flipped.

But I have three suggestions:

1. When widgets do enable perfect clean flipping, use it

2. When an app has two directional matching widgets, e.g. left and right
arrows, simply switch between then instead of fliping. This will
probably require an "matching image" object property

3. Add guidance to the Gnome devel docs, which explains how to write
just few extra simple lines which makes your app more RTL-ready, so that
we won't need to "hunt" and fix the same bugs again and again in each
new app/design/implementation/version

On ד', 2013-10-16 at 23:25 +0200, Dov Grobgeld wrote:
No, I don't think it is universally reasonable. Because in general an
icon may have a style that is broken when the image is flipped.
Imagine e.g. if the buttons in some style contains arrows that were
drawn with an elliptical pen slanted at 45 degrees to the right. In
such a case the left and the right arrow are not a mirror image of one
another. Another example is if the style contains a drawing with
dropshadow to the right. Horizontally flipping the image would put the
drop shadow to the left, which would be inconsistent with the rest of
the theme. You may claim that if this was done throughout the
application then it wouldn't make any difference, but if e.g. have an
embedded label with "Latin name: " and an LTR widget then it would be
inconsistant within the application. Even between applications that
have either LTR or RTL directionality on the desktop would look

Thus, imo there is no automatic solution, but you need to create
dedicated RTL images to make things look good in a RTL environment.


On Wed, Oct 16, 2013 at 11:58 PM, fr33domlover
<fr33domlover mailoo org> wrote:
        Hello Gtk+ developers,
        My native language is an RTL language. I've been examining
        several RTL
        problems in GNOME software recently, and I noticed some
        Some of them are related to text alignment and fonts, which I
        won't talk
        about this time because I haven't found a universal solutio.
        But I think
        I did find a solution for images.
        It is very common for images where the direction matters, such
        prev/next arrows, to be in the wrong direction when apps run
        in RTL
        locales. So far, a volunteer has been fixing these problems by
        hand by
        sending patches to all GNOME software containing the problem.
        example, the prev/next arrows in Epiphany and in Evolution's
        notification-bar bubble.
        Here are some related bugs:
        Instead of doing it by hand, or trying to teach developers how
        to make
        their apps direction-aware, I found a universal solution which
        a bit of work once, and will work after that without any
        The idea is: Directional Images.
        Example: An arrow is a directional image. The direction of the
        matters. When an arrow icon is rendered in RTL locales, it
        should be
        rendered horizontally flipped, so right becomes left and left
        A folder image is a non-directional image. Changing its
        doesn't make any sense or different in any direction or
        locale. The same
        is true for people's faces, an image of the Earth, a map of a
        city, etc.
        The solution I suggest is to add a "directional" boolean
        property to
        GTK's image class used for icons. The property will be stored
        as image
        metadata, and set by the designer of the image. After that,
        the code
        which renders the menu/toolbar icons will just need to check
        if the
        image is directional and the locale is RTL. If both are true,
        draw the
        image horizontally flipped. Otherwise, draw as usual.
        I believe it shouldn't take extra resources, because the
        drawing loop
        will simply need to fill pixels from the other side. No extra
        is required (unless computing "size - x" in each loop
        iteration is too
        much slower than just "x", which I doubt").
        Is it possible? Does it sound a reasonable approach?
        gtk-devel-list mailing list
        gtk-devel-list gnome org

[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]