Re: Images disappear after Display Resolution Change

[Ondrej Florian]

This also happens (sometimes) when you attach external display.
It is certainly related to change of display resolution and easily reproducible 
by invoking xrandr.

I guess that GNUstep is caching some kind of data that needs to be invalidated.


On 2023-12-28 14:25:21 +0100 Sebastian Reitenbach 
<sebastia@l00-bugdead-prods.de> wrote:

> Hi,
> 
> On Tuesday, December 26, 2023 19:52 CET, Tom Sheffler 
> <tom.sheffler@gmail.com> wrote:
> 
>> I’ve recently installed gs-desktop (from github.com/onflapp/gs-desktop/ 
>> <http://github.com/onflapp/gs-desktop/>) on Debian 12 into a clean 
>> partition in a System76 laptop.  It all works very nicely as a desktop 
>> environment.
> 
>> I have noticed an annoying problem when I change resolutions - I seem to do 
>> this often: when I plug in an external monitor I size things one way, and 
>> when not connected I size the display another way.  I’ve investigated the 
>> problem, and do not have a good fix. I’m hoping that by sharing my 
>> experience here someone might be able to shed some light on the subject.
> 
> 
>> Upon resizing the main screen, icons and images disappear.  The commands I 
>> use are
> 
>>     - xrandr —output eDP-1 —mode 1400x1050
>>     - xrandr —output eDP-1 —mode 1600x900
> 
>> After changing resolutions, images and icons in the following apps have 
>> been seen to dissappear
>>    - GWorkspace
>>    - Gorm
>>    - nextspace/Preferences
>>    - gs-desktop/Applications/VolMon
>>    - gs-desktop/Applications/MountUp
> 
>> The picture below shows two versions of GWorkspace FileViewer.  The one on 
>> top is GWorkspace installed “as-is” and shown after changing the 
>> resolution of the display.  The large icons and the small icons are all 
>> gone.  They do not reappear after any amount of fiddling with controls or 
>> themes I attempt.
> 
>> The bottom FileViewer is a modified copy of GWorkspace that has been 
>> changed to add a new menu item called “Redraw” that does a couple of 
>> things.  It deletes image caches in various places and then calls [NSApp 
>> updateWindows].  This does not immediately fix the images, but after 
>> scolling around the images get refreshed as the caches are rebuilt.
>> The two “DIFF” files attached in this message show what code 
>> modifications I made to support the “Redraw” menu item.
> 
>> While clearing the caches helps fix the problem, I don’t really believe 
>> I’m on totally the right track for a permanent fix across applications. 
>> So I’m looking for suggestions or other insights.  Or at least that this 
>> info helps someone else one day.
> 
>> ===
> 
>> I”ve also investigated an entirely different track, changing the 
>> following line in NSImage.m
>>      _cacheMode = NSImageCacheDefault;
>> to
>>      _cacheMode = NSImageCacheNever;
> 
>> and rebuilding.  In GWorkspace, this fixes the Large icons, but breaks the 
>> Small icons.  It does, however, also fix the module images in the 
>> Nextspace/Preferences app so that they do not disappear upon resolution 
>> changes.
> 
>> Thanks,
>> T
> 
> just recently, a few weeks ago, I exchanged my desktops Nvidia card, with 2 
> monitors (2xHD), with a AMD based graphics car, and a single monitor UWQHD. 
> I'm on OpenBSD, using latest gnustep releases, and after suspend/resume 
> cycle, I see the same.
> Haven't had time to dig into it, thought might be because of graphics GPU 
> driver change, or resolution change etc.
> But it's only GNUstep applications that loose the images, most notably 
> GWorkspace.
> 
> Sebastian
> 
> 
> 
>