rename settrans to compton-trans, add manpage.

bin/compton-trans

@@ -0,0 +1,92 @@
+#!/bin/bash
+
+# transset in a bash script
+# Copyright (c) 2011-2012, Christopher Jeffrey
+
+# Usage:
+# by window id
+#   settrans -w "$WINDOWID" -o 75
+# by name
+#   settrans -n "urxvt" -o 75
+# by current window
+#   settrans -c -o 75
+# by selection
+#   settrans -s -o 75
+# increment current window 5%
+#   settrans -c -o +5
+
+if test -z "$(which xprop)" -o -z "$(which xwininfo)"; then
+  echo "Please install x11-utils/xorg-xprop/xorg-xwininfo." >& 2
+  exit 1
+fi
+
+window=
+opacity=
+cur=
+root=
+parent=
+active=
+i=
+
+while getopts "scn:w:o:" option; do
+  case "$option" in
+    s) window="" ;;
+    c)
+      active=$(xprop -root -notype "_NET_ACTIVE_WINDOW" \
+        | sed 's/^.*\(0x\S*\).*$/\1/')
+      window="-id $active"
+    ;;
+    n) window="-name $OPTARG" ;;
+    w) window="-id $OPTARG" ;;
+    o) opacity="$OPTARG" ;;
+  esac
+done
+
+root=$(xwininfo -all -root \
+  | grep "Root window id" \
+  | sed 's/^.*\(0x\S*\).*$/\1/')
+
+parent=$window
+i=0
+while true; do
+  parent=$(xwininfo -all $parent \
+    | grep Parent \
+    | sed 's/^.*\(0x\S*\).*$/\1/')
+
+  if test "$parent" = "$root"; then
+    break
+  fi
+
+  parent="-id $parent"
+  window=$parent
+
+  i=$((i+1))
+  if test $i -ge 1000; then
+    echo "An error occurred while traversing up the window tree." >& 2
+    echo "Please report this to https://github.com/chjj/compton/issues." >& 2
+    echo "Please mention your WM and versions of xwininfo/xprop." >& 2
+    exit 1
+  fi
+done
+
+inc=$(echo "$opacity" | sed 's/^\(+\|-\).*$\|^.*$/\1/')
+if test -n "$inc"; then
+  cur=$(xprop $window -notype "_NET_WM_WINDOW_OPACITY" \
+    | sed 's/^.*\b\([0-9]\+\).*$\|^.*$/\1/')
+  test -z "$cur" && cur=$((0xffffffff))
+  cur=$((cur*100/0xffffffff))
+  opacity=$(echo "$opacity" | sed 's/\(\+\|\-\)//')
+  if test "$inc" = "+"; then
+    opacity=$((cur+opacity))
+  else
+    opacity=$((cur-opacity))
+  fi
+fi
+
+if test -n "$opacity" -a -n "$window"; then
+  test $opacity -lt 0 && opacity=0
+  test $opacity -gt 100 && opacity=100
+  opacity=$((opacity*0xffffffff/100))
+  xprop $window -f _NET_WM_WINDOW_OPACITY 32c \
+    -set _NET_WM_WINDOW_OPACITY "$opacity"
+fi