Subject: bug#20432: GDK_SCALE=2 GDK_DPI_SCALE=0.5 destroys GTK+ 3 scroll bar

From: "Felix E. Klee" <[email-masked]>
Date: Thu, 14 May 2015 12:59:36 +0100

On Thu, May 14, 2015 at 12:34 PM, Jan Djärv <[email-masked]> wrote:
> This GTK feature is very poorly designed.

HiDPI scaling works beautifully in various other GTK+ 3 applications.

> We can not support it correctly, as we don't use Gtk+ exclusively.

Thanks for the explanation.

> Also, the Gtk+ code blindly multiplies anything with GTK_SCALE. So for
> example, given GTK_SCALE=2, if we have font size 15, it becomes 30.

That is what `GDK_DPI_SCALE` is for. Example:

    export GDK_SCALE=2
    export GDK_DPI_SCALE=0.5

> So there will be glitches, live with it.

It’s not for me. I set up a HiDPI machine for a friend who’s turning
eighty this year. While he has great vision given his age, some UI
elements are just too small without scaling. They are barely visible.

This is a big issue, not something that should be ignored. Get access to
a HiDPI screen, and you’ll see what I mean.

> But at least we draw things correctly in the trunk now.

Great!