clean makefile, add transset script

Makefile

@@ -1,10 +1,9 @@
 PACKAGES = x11 xcomposite xfixes xdamage xrender
-LIBS = `pkg-config --libs ${PACKAGES}` -lm
-INCS = `pkg-config --cflags ${PACKAGES}`
+LIBS = `pkg-config --libs $(PACKAGES)` -lm
+INCS = `pkg-config --cflags $(PACKAGES)`
 CFLAGS = -Wall
 PREFIX = /usr/local
-MANDIR = ${PREFIX}/share/man/man1
-
+MANDIR = $(PREFIX)/share/man/man1
 OBJS = compton.o
 
 .c.o:
@@ -16,13 +15,13 @@ compton: $(OBJS)
 $(OBJS): compton.h
 
 install: compton
-	@cp -t ${PREFIX}/bin compton
-	@[ -d "${MANDIR}" ] \
-	  && cp -t "${MANDIR}" compton.1
+	@cp -t $(PREFIX)/bin compton
+	@[ -d "$(MANDIR)" ] \
+	  && cp -t "$(MANDIR)" compton.1
 
 uninstall:
-	@rm -f ${PREFIX}/bin/compton
-	@rm -f ${MANDIR}/compton.1
+	@rm -f $(PREFIX)/bin/compton
+	@rm -f $(MANDIR)/compton.1
 
 clean:
 	rm -f $(OBJS) compton

trans

@@ -0,0 +1,76 @@
+#!/bin/bash
+
+# transset in a bash script
+# copyright (c) 2011, christopher jeffrey
+
+# usage:
+# by window id
+#trans -w "$WINDOWID" -o 75
+# by name
+#trans -n "urxvt" -o 75
+# by current window
+#trans -c -o 75
+# by selection
+#trans -s -o 75
+
+[ -z "$(which xprop)" ] && \
+  echo "Please install x11-utils/xorg-xprop."
+
+window=
+opacity=
+cur=
+root=
+parent=
+active=
+
+while getopts "scn:w:o:" OPTION; do
+  case "$OPTION" in
+    s) window="" ;;
+    c)
+      active=$(xprop -root -notype \
+        | grep "_NET_ACTIVE_WINDOW:" \
+        | sed 's/^.*\(0x\S*\).*$/\1/')
+      window="-id $active"
+    ;;
+    n) window="-name $OPTARG" ;;
+    w) window="-id $OPTARG" ;;
+    o) opacity="$OPTARG" ;;
+  esac
+done
+
+# should probably use a while loop
+# to get the toplevel window
+
+parent=$(xwininfo -all $window \
+  | grep Parent \
+  | sed 's/^.*\(0x\S*\).*$/\1/')
+
+root=$(xwininfo -all -root \
+  | grep "Root window id" \
+  | sed 's/^.*\(0x\S*\).*$/\1/')
+
+if [ "$parent" != "$root" ]; then
+  window="-id $parent"
+fi
+
+inc=$(echo "$opacity" | sed 's/^\(+\|-\).*$\|^.*$/\1/')
+if [ -n "$inc" ]; then
+  cur=$(xprop $window -notype "_NET_WM_WINDOW_OPACITY" \
+    | sed 's/^.*\([0-9]\+\).*$\|^.*$/\1/')
+  [ -z "$cur" ] && cur=$((0xffffffff))
+  cur=$((cur*100/0xffffffff))
+  opacity=$(echo "$opacity" | sed 's/\(\+\|\-\)//')
+  if [ "$inc" = "+" ]; then
+    opacity=$((cur+opacity))
+  else
+    opacity=$((cur-opacity))
+  fi
+fi
+
+if [ -n "$opacity" ] && [ -n "$window" ]; then
+  [ $opacity -le 0 ] && opacity=0
+  [ $opacity -ge 100 ] && opacity=100
+  opacity=$((opacity*0xffffffff/100))
+  xprop $window -f _NET_WM_WINDOW_OPACITY 32c \
+    -set _NET_WM_WINDOW_OPACITY "$opacity"
+fi