Felix Miata wrote:

> deloptes composed on 2016-12-01 22:08 (UTC+0100):
> 
>> Felix Miata wrote:
> 
>> If you change dpi and restart the window manager I would expect that
>> icons look different. Perhaps you can test that
> 
> Did you happen to load the images below? They show at least one at same
> size (Firefox), and three not (upper right), the latter of which I suppose
> are entirely different icons used on account of the elevated DPI, but also
> could be SVGs rather than bitmaps.
> 
> For my eyes, most icons are sized too small to describe their purpose
> (those in Gimp and LibreOffice are among the worst offenders), so that I
> either see them as flags, a target to hit with mouse pointer after seeing
> a tooltip that describes their purpose, or as a complete waste of space. I
> prefer meanings conveyed by words, but well recognize sometimes words
> simply cannot express that which is obvious in a picture.
> 

In the control panel there is option to select the icon size for the theme.
I prefer 48px - look there.

>>> As an additional exercise, compare the following (from separate sessions
>>> using configurations differing only in configured DPI (xrandr in startup
>>> script)). Note that the titlebar's right side's icons are larger, but
>>> not the left's (Firefox) icon, and that nothing within the application's
>>> web content area seems differently sized (movies, images and most web
>>> text are sized in px): http://fm.no-ip.com/SS/dt1680x108.png
>>> http://fm.no-ip.com/SS/dt1680x144.png
> 
> 
> 
>> Under look and feel -> fonts you can enforce the DPI
> 
> Not all environments make such an offer. I prefer that a DPI specification
> in most cases be made prior to, at, or as early as possible during Xorg
> initialization, in any event prior to a particular user's exposure to WM
> output.

Anyway - I think what we learned is that DPI must be set when X is starting.
The setting does not do anything different.

regards