A simple gnome desktop background changer even given time

gnome-bg-carrousel.sh

#!/usr/bin/env bash

# author: Erich Nascimento <[email protected]>
# created: 2014-07-26 01:25
# TODO: Implements transitions maybe using gsettings ... picture-opacity
#
# references: 
#   - Inspiration: http://askubuntu.com/a/69500/184517
#   - Scripting approach: https://github.com/visionmedia/n/blob/master/bin/n
#   - Sleep: http://www.cyberciti.biz/faq/linux-unix-sleep-bash-scripting/
#   - Default param: http://www.tldp.org/LDP/abs/html/parameter-substitution.html
#   - Loop over files: http://www.cyberciti.biz/faq/bash-loop-over-file/
#
# Sorry my poor english. LOL

#
# Usage
#

# You can export 2 vars in your ~/.bash_profile :

# Define image dir to iterate. Default /usr/share/backgrounds
# export GNOME_BG_CARROUSEL_DIR=~/Pictures

# Define duration time. Default 10s
#export GNOME_BG_CARROUSEL_DURATION=30s



#
# Initialize
#

IMAGES_DIR=${GNOME_BG_CARROUSEL_DIR-/usr/share/backgrounds}

DURATION=${GNOME_BG_CARROUSEL_DURATION-10s}

#
# Ensure we have gsettings installed
#

GSETTINGS=

command -v gsettings > /dev/null && GSETTINGS="gsettings"

test -z "$GSETTINGS" && printf "\n \033[31mError: gsettings is required :( \033[0m\n\n" && exit 1

# Infinite looping
while true; do
	for file in $IMAGES_DIR/* 
	do
		[ -f "$file" ] && gsettings set org.gnome.desktop.background picture-uri "file://$file"
		sleep $DURATION
	done
done