diff --git a/bin/compton-trans b/bin/compton-trans
index f813433..6beeabf 100755
--- a/bin/compton-trans
+++ b/bin/compton-trans
@@ -7,6 +7,7 @@
 #
 
 # Usage:
+#  $ compton-trans [options] [+|-]opacity
 # By window id
 #   $ compton-trans -w "$WINDOWID" 75
 # By name
@@ -18,117 +19,190 @@
 #   $ compton-trans -s 75
 # Increment current window 5%
 #   $ compton-trans -c +5
+# Delete current window's opacity
+#   $ compton-trans -c --delete
+# Reset all windows
+#   $ compton-trans --reset
 
 # "command" is a shell built-in, faster than "which"
 if test -z "$(command -v xprop)" -o -z "$(command -v xwininfo)"; then
-  echo "Please install x11-utils/xorg-xprop/xorg-xwininfo." >& 2
+  echo 'Please install x11-utils/xorg-xprop/xorg-xwininfo.' >& 2
   exit 1
 fi
 
+# Variables
+active=
+wprefix=
 window=
 opacity=
 cur=
-i=
+action=
+treeout=
+wid=
+topmost=
+lineno=
+option=
+v=
 
-# Read options
-while getopts "scn:w:o:" option; do
-  case "$option" in
-    s) wprefix=''; window='' ;;
-    c)
-      active=$(xprop -root -notype "_NET_ACTIVE_WINDOW" \
-        | sed 's/^.*\(0x\S*\).*$/\1/')
-      wprefix='-id '; window="$active"
-    ;;
-    n) wprefix='-name '; window="$OPTARG" ;;
-    w) wprefix='-id '; window="$OPTARG" ;;
-    o) opacity="$OPTARG" ;;
-    \?) exit 1;;
-  esac
+# Workaround: replace '-5' with '~5' so as not to confuse getopts.
+for v in "$@"; do
+  shift && set -- "$@" "$(echo "$v" | sed 's/^-\([0-9]\+%\?\)$/~\1/')"
 done
 
-# Read positional arguments
-shift $(($OPTIND - 1))
-[ -n "$1" ] && opacity="$1"
+# This takes into account the fact that getopts stops on
+# any argument it doesn't recongize or errors on. This
+# allows for things like `compton-trans -5` as well
+# as `compton-trans -c +5 -s` (contrived example).
+while test $# -gt 0; do
+  # Reset option index
+  OPTIND=1
+
+  # Read options
+  while getopts 'scrdgn:w:o:-:' option "$@"; do
+    if test "$option" = '-'; then
+      case "$OPTARG" in
+        select | current | reset | delete | get)
+          v=''
+        ;;
+        name | window | opacity)
+          eval v=\$$OPTIND
+          OPTIND=$((OPTIND + 1))
+        ;;
+        name=* | window=* | opacity=*)
+          v=$(echo "$OPTARG" | sed 's/^[^=]\+=//')
+        ;;
+        *)
+          echo "$0: illegal option $OPTARG" >& 2
+          exit 1
+        ;;
+      esac
+      option=$(echo "$OPTARG" | cut -c 1)
+      OPTARG=$v
+    fi
+    case "$option" in
+      s) wprefix=''; window='' ;;
+      c)
+        active=$(xprop -root -notype _NET_ACTIVE_WINDOW \
+          | sed 's/^.*\(0x\S*\).*$/\1/')
+        wprefix='-id'; window=$active
+      ;;
+      r) action='reset' ;;
+      d) action='delete' ;;
+      g) action='get' ;;
+      n) wprefix='-name'; window=$OPTARG ;;
+      w) wprefix='-id'; window=$OPTARG ;;
+      o) opacity=$OPTARG ;;
+      \?) exit 1 ;;
+    esac
+  done
+
+  # Read positional arguments
+  shift $((OPTIND - 1))
+  test -n "$1" && opacity=$1 && shift
+done
+
+# clean up opacity. xargs == a poor man's trim.
+opacity=$(echo "$opacity" | xargs | sed 's/%//g' | sed 's/^~\([0-9]\+\)$/-\1/')
 
 # Validate opacity value
-if [ -z "$opacity" ]; then
-  echo "No opacity specified."
+if test -z "$action" && ! echo "$opacity" | grep -q '^[+-]\?[0-9]\+$'; then
+  echo "Invalid opacity specified: $opacity."
   exit 1
 fi
 
-opacity="$(echo "$opacity" \
-  | sed -rn 's/^[[:space:]]*([+-]?[[:digit:]]+)[[:space:]]*$/\1/p')"
-
-if [ -z "$opacity" ]; then
-  echo "Invalid opacity value."
-  exit 1
+# Reset opacity for all windows
+if test x"$action" = x'reset'; then
+  xwininfo -root -tree \
+  | sed -n 's/^     \(0x[[:xdigit:]]*\).*/\1/p' \
+  | while IFS=$'\n' read wid; do
+    xprop -id "$wid" -remove _NET_WM_WINDOW_OPACITY
+  done
+  exit 0
 fi
 
 # Get ID of the target window
-if [ -z "$wprefix" ]; then
+if test -z "$wprefix"; then
   treeout=$(xwininfo -children -frame)
 else
-  treeout=$(xwininfo -children $wprefix"$window")
+  test "$wprefix" = '-id' \
+    && ! echo "$window" | grep -q '^\(0x\)\?[0-9a-fA-F]\+$' \
+    && echo 'Bad window ID.' && exit 1
+  treeout=$(xwininfo -children $wprefix "$window")
 fi
 
 wid=$(echo "$treeout" | sed -n 's/^xwininfo:.*: \(0x[[:xdigit:]]*\).*$/\1/p')
 
-if [ -z "$wid" ]; then
-  echo "Failed to find window."
+if test -z "$wid"; then
+  echo 'Failed to find window.'
   exit 1
 fi
 
 # Make sure it's not root window
-if echo "$treeout" | fgrep "Parent window id: 0x0" > /dev/null; then
-  echo "Cannot set opacity on root window."
+if echo "$treeout" | fgrep -q 'Parent window id: 0x0'; then
+  echo 'Cannot set opacity on root window.'
   exit 1
 fi
 
 # If it's already the topmost window
-if echo "$treeout" | grep "Parent window id: 0x[[:xdigit:]]* (the root window)" > /dev/null; then
-  topmost="$wid"
+if echo "$treeout" | grep -q 'Parent window id: 0x[[:xdigit:]]* (the root window)'; then
+  topmost=$wid
 else
   # Get the whole window tree
-  treeout="$(xwininfo -root -tree)"
+  treeout=$(xwininfo -root -tree)
 
-  if [ -z "$treeout" ]; then
-    echo "Failed to get root window tree."
+  if test -z "$treeout"; then
+    echo 'Failed to get root window tree.'
     exit 1
   fi
 
   # Find the line number of the target window in the window tree
-  lineno="$(echo -n "$treeout" | grep -nw "$wid" | head -n1 | cut -d ':' -f 1)"
+  lineno=$(echo -n "$treeout" | grep -nw "$wid" | head -n1 | cut -d ':' -f 1)
 
-  if [ -z "$lineno" ]; then
-    echo "Failed to find window in window tree."
+  if test -z "$lineno"; then
+    echo 'Failed to find window in window tree.'
     exit 1
   fi
 
   # Find the highest ancestor of the target window below
-  topmost=$(echo -n "$treeout" | head -n $(($lineno + 1)) | sed -n 's/^     \(0x[[:xdigit:]]*\).*/\1/p' | tail -n1)
+  topmost=$(echo -n "$treeout" \
+    | head -n $((lineno + 1)) \
+    | sed -n 's/^     \(0x[[:xdigit:]]*\).*/\1/p' \
+    | tail -n 1)
 fi
 
-if [ -z "$topmost" ]; then
-  echo "Failed to find the highest parent window below root of the" \
-    "selected window."
+if test -z "$topmost"; then
+  echo 'Failed to find the highest parent window below root of the' \
+    'selected window.'
   exit 1
 fi
 
-# Calculate the desired opacity
-if echo "$opacity" | grep '^[+-]' > /dev/null; then
-  sign=$(echo "$opacity" | cut -b1)
-  cur=$(xprop -id "$topmost" -notype "_NET_WM_WINDOW_OPACITY" \
-    | sed 's/^.*\b\([0-9]\+\).*$\|^.*$/\1/')
-  [ -z "$cur" ] && cur=0xffffffff
-  cur=$((cur * 100 / 0xffffffff))
-  opacity="$(echo "$opacity" | sed 's/^[+-]//')"
-    opacity=$(($cur $sign $opacity))
+# Remove the opacity property.
+if test x"$action" = x'delete'; then
+  xprop -id "$topmost" -remove _NET_WM_WINDOW_OPACITY
+  exit 0
 fi
 
-[ $opacity -lt 0 ] && opacity=0
-[ $opacity -gt 100 ] && opacity=100
+# Get current opacity.
+cur=$(xprop -id "$topmost" -notype _NET_WM_WINDOW_OPACITY \
+  | sed 's/^.*\b\([0-9]\+\).*$\|^.*$/\1/')
+test -z "$cur" && cur=0xffffffff
+cur=$((cur * 100 / 0xffffffff))
+
+# Output current opacity.
+if test x"$action" = x'get'; then
+  echo "$cur"
+  exit 0
+fi
+
+# Calculate the desired opacity
+if echo "$opacity" | grep -q '^[+-]'; then
+  opacity=$((cur + opacity))
+fi
+
+test $opacity -lt 0 && opacity=0
+test $opacity -gt 100 && opacity=100
 
 # Set opacity
-opacity=$(($opacity * 0xffffffff / 100))
+opacity=$((opacity * 0xffffffff / 100))
 xprop -id "$topmost" -f _NET_WM_WINDOW_OPACITY 32c \
   -set _NET_WM_WINDOW_OPACITY "$opacity"