Added rendering via Cario for semi-transparent window when using

compositing. Code is messy but works.

cb-openbox-logout.py

@@ -4,22 +4,37 @@ import gtk, os
 from PIL import Image, ImageFilter
 import ConfigParser
 import StringIO
+import logging
+import cairo
 
 class OpenboxLogout():
     def __init__(self, config=None):
         
         self.load_config(config)
-        
+               
         self.window = gtk.Window()        
         self.window.set_title("Log Out ..")
+        
         self.window.connect("destroy", self.quit)
         self.window.connect("key-press-event", self.on_keypress)
+        self.window.connect("window-state-event", self.on_window_state_change)
+        
+        if self.rendered_effects == False:     
+            if not self.window.is_composited():
+                logging.debug("No compositing, enabling rendered effects")
+                # Window isn't composited, enable rendered effects
+                self.rendered_effects = True
+            else:
+                # Link in Cairo rendering events
+                self.window.connect('expose-event', self.on_expose)
+                self.window.connect('screen-changed', self.on_screen_changed)
+                self.on_screen_changed(self.window)
+        
         self.window.set_size_request(620,200)
         self.window.modify_bg(gtk.STATE_NORMAL, gtk.gdk.color_parse("black"))
-        self.window.set_decorated(gtk.FALSE)
+                   
+        self.window.set_decorated(False)
         self.window.set_position(gtk.WIN_POS_CENTER)
-
-        self.window.connect("window-state-event", self.on_window_state_change)
         
         self.mainpanel = gtk.Fixed()
         self.window.add(self.mainpanel)
@@ -50,42 +65,51 @@ class OpenboxLogout():
         self.label_info.modify_fg(gtk.STATE_NORMAL, gtk.gdk.color_parse("white"))
         self.mainpanel.put(self.label_info, x+490, y+170)
         
-        w = gtk.gdk.get_default_root_window()
-        sz = w.get_size()
-        pb = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB,False,8,sz[0],sz[1])
-        pb = pb.get_from_drawable(w,w.get_colormap(),0,0,0,0,sz[0],sz[1])
+        if self.rendered_effects == True:
+        
+            logging.debug("Stepping though render path")
+            w = gtk.gdk.get_default_root_window()
+            sz = w.get_size()
+            pb = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB,False,8,sz[0],sz[1])
+            pb = pb.get_from_drawable(w,w.get_colormap(),0,0,0,0,sz[0],sz[1])
 
-        if self.blur_background == True:
-            # Convert Pixbuf to PIL Image
-            width,height = pb.get_width(),pb.get_height()
-            pilimg = Image.fromstring("RGB",(width,height),pb.get_pixels() )
+            logging.debug("Blur Enabled: %s" % self.blur_background)
+            if self.blur_background == True:
+                logging.debug("Rendering Blur")
+                # Convert Pixbuf to PIL Image
+                width,height = pb.get_width(),pb.get_height()
+                pilimg = Image.fromstring("RGB",(width,height),pb.get_pixels() )
 
-            # Blur the image
-            pilimg = pilimg.filter(ImageFilter.BLUR)
+                # Blur the image
+                pilimg = pilimg.filter(ImageFilter.BLUR)
     
-            # "Convert" the PIL to Pixbuf via PixbufLoader
-            buf = StringIO.StringIO()
-            pilimg.save(buf, "ppm")
-            del pilimg
-            loader = gtk.gdk.PixbufLoader("pnm")
-            loader.write(buf.getvalue())
-            pixbuf = loader.get_pixbuf()
+                # "Convert" the PIL to Pixbuf via PixbufLoader
+                buf = StringIO.StringIO()
+                pilimg.save(buf, "ppm")
+                del pilimg
+                loader = gtk.gdk.PixbufLoader("pnm")
+                loader.write(buf.getvalue())
+                pixbuf = loader.get_pixbuf()
 
-            # Cleanup IO
-            buf.close()
-            loader.close()
+                # Cleanup IO
+                buf.close()
+                loader.close()
+            else:
+                pixbuf = pb
+                del pb
+
+            pixmap, mask = pixbuf.render_pixmap_and_mask()
+            # width, height = pixmap.get_size()
         else:
-            pixbuf = pb
-
-        pixmap, mask = pixbuf.render_pixmap_and_mask()
-        # width, height = pixmap.get_size()
+            pixmap = None
+    
         self.window.set_app_paintable(True)
         self.window.resize(screen_x, screen_y)
         self.window.realize()
-        self.window.window.set_back_pixmap(pixmap, False)
+        if pixmap:
+            self.window.window.set_back_pixmap(pixmap, False)
         self.window.move(0,0)
-        del pixbuf
-        del pixmap                   
+                  
 
     def load_config(self, config):
     
@@ -95,7 +119,52 @@ class OpenboxLogout():
         parser = ConfigParser.SafeConfigParser()
         parser.read(config)
         
-        self.blur_background = parser.get("looks", "blurbackground")
+        self.blur_background = parser.getboolean("looks", "blur")
+        self.opacity = parser.getint("looks", "opacity")
+        
+        print self.blur_background
+        
+        if self.blur_background:
+            self.rendered_effects = True
+        else:
+            self.rendered_effects = False
+
+    def on_expose(self, widget, event):
+       
+        cr = widget.window.cairo_create()
+    
+        if self.supports_alpha == True:
+            cr.set_source_rgba(1.0, 1.0, 1.0, 0.0) # Transparent
+        else:
+            cr.set_source_rgb(1.0, 1.0, 1.0) # Opaque white
+    
+        # Draw the background
+        cr.set_operator(cairo.OPERATOR_SOURCE)
+        cr.paint()
+
+        (width, height) = widget.get_size()
+        cr.set_source_rgba(0, 0, 0, .5)
+       
+        cr.rectangle(0, 0, width, height)
+        cr.fill()
+        cr.stroke()
+        return False
+        
+    def on_screen_changed(self, widget, old_screen=None):
+       
+        # To check if the display supports alpha channels, get the colormap
+        screen = widget.get_screen()
+        colormap = screen.get_rgba_colormap()
+        if colormap == None:
+            logging.debug('Screen does not support alpha channels!')
+            colormap = screen.get_rgb_colormap()
+            self.supports_alpha = False
+        else:
+            logging.debug('Screen supports alpha channels!')
+            self.supports_alpha = True
+    
+        # Now we have a colormap appropriate for the screen, use it
+        widget.set_colormap(colormap)
 
     def on_window_state_change(self, widget, event, *args):
         if event.new_window_state & gtk.gdk.WINDOW_STATE_FULLSCREEN:
@@ -144,5 +213,7 @@ class OpenboxLogout():
         gtk.main()
 
 if __name__ == "__main__":
+
+     logging.basicConfig(level=logging.DEBUG)
      app = OpenboxLogout('openbox-logout.conf')
      app.run()