This will show you how to enable the GL slideshow screensaver
To enable it go to:
System–>Preferences–>Screensaver–>GLSlideshow
Configure GLSlideshow
To change the path to the pictures edit ~/.xscreensaver
cd ~
echo "imageDirectory: /path/to/pictures" >> .xscreensaver
echo "chooseRandomImages: True" >> .xscreensaver
You can edit the options by changing the runtime arguments
sudo vi /usr/share/applications/screensavers/glslideshow.desktop
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# Exec=glslideshow -root
#Exec=glslideshow -root -duration 16 -pan 6 -fade 6 -zoom 60
Exec=/usr/lib/xscreensaver/glslideshow -root -duration 10 -pan 10 -fade 2 -zoom 75 -fps
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