convert GLSL shader to gnome wallpaper slideshow

shader-to-wallpaper.sh

#!/usr/bin/env bash

shader=$1 # first argument is path to shader
renderstart=0 # seconds
renderend=20

resolutionx=1920
resolutiony=1080
wallduration=20 # seconds, minimum 1

target_dir=`basename $shader`_wallpaper

rm -r $target_dir
mkdir $target_dir
cd $target_dir

# build & install from https://github.com/patriciogonzalezvivo/glslViewer
glslViewer $shader --headless -w $resolutionx -h $resolutiony -e sequence,$renderstart,$renderend -e q

# build & install from https://github.com/almet/gnome-background-generator
gnome-background-generator -d $wallduration -t 0 ./

# set the new background, forcing a config change
dconf write /org/gnome/desktop/background/picture-uri "'/dev/null'"
dconf write /org/gnome/desktop/background/picture-uri "'file://`pwd`/dynamic-wallpaper.xml'"