added more background related stuff

home-manager/dotfiles/niri/background.sh

@@ -0,0 +1,28 @@
+#!/bin/sh
+# Changes the wallpaper to a randomly chosen image in a given directory
+# at a set interval.
+
+DEFAULT_INTERVAL=300 # In seconds
+
+if [ $# -lt 1 ] || [ ! -d "$1" ]; then
+  printf "Usage:\n\t\e[1m%s\e[0m \e[4mDIRECTORY\e[0m [\e[4mINTERVAL\e[0m]\n" "$0"
+  printf "\tChanges the wallpaper to a randomly chosen image in DIRECTORY every\n\tINTERVAL seconds (or every %d seconds if unspecified)." "$DEFAULT_INTERVAL"
+  exit 1
+fi
+
+# See swww-img(1)
+RESIZE_TYPE="fit"
+export SWWW_TRANSITION_FPS="${SWWW_TRANSITION_FPS:-60}"
+export SWWW_TRANSITION_STEP="${SWWW_TRANSITION_STEP:-2}"
+
+while true; do
+  find "$1" -type f |
+    while read -r img; do
+      echo "$(</dev/urandom tr -dc a-zA-Z0-9 | head -c 8):$img"
+    done |
+    sort -n | cut -d':' -f2- |
+    while read -r img; do
+      swww img --resize="$RESIZE_TYPE" "$img"
+      sleep "${2:-$DEFAULT_INTERVAL}"
+    done
+done