remove enable_real_transparency setting and instead attempt to determine it based on the actual capabilities of the current display

doc/terminator_config.5

@@ -36,10 +36,6 @@ These are the options Terminator currently supports in the global_config section
 Control how focus is given to terminals. 'click' means the focus only moves to a terminal after you click in it. 'sloppy' means the focus will follow the mouse pointer. 'system' means the focus will match that used by a GNOME window manager.
 Default value: \fBclick\fR
 .TP
-.B enable_real_transparency\fR (boolean)
-If true, Terminator will try to use real transparency if possible.
-Default value: \fBFalse\fR
-.TP
 .B handle_size
 Controls the width of the separator between terminals. Anything outside the range 0-5 (inclusive) will be ignored and use your default theme value.
 Default value: \fB-1\fR

terminatorlib/config.py

@@ -77,7 +77,6 @@ except ImportError:
 DEFAULTS = {
         'global_config':   {
             'focus'                 : 'click',
-            'enable_real_transparency'  : True,
             'handle_size'           : -1,
             'geometry_hinting'      : True,
             'window_state'          : 'normal',

terminatorlib/terminal.py

@@ -613,10 +613,23 @@ for %s (%s)' % (name, urlplugin.__class__.__name__))
             dbg('setting opacity: %d' % opacity)
             self.vte.set_opacity(opacity)
 
-        if self.config['background_type'] == 'transparent' and \
-                self.config['enable_real_transparency'] == False:
-            dbg('setting background_transparent=True')
-            self.vte.set_background_transparent(True)
+        # This is quite hairy, but the basic explanation is that we should
+        # set_background_transparent(True) when we have no compositing and want
+        # fake background transparency, otherwise it should be False.
+        if not self.composite_support:
+            # We have no compositing support, fake background only
+            background_transparent = True
+        else:
+            if self.vte.is_composited() == False:
+                # We have compositing and it's enabled. no fake background.
+                background_transparent = True
+            else:
+                # We have compositing, but it's not enabled. fake background
+                background_transparent = False
+
+        if self.config['background_type'] == 'transparent':
+            dbg('setting background_transparent=%s' % background_transparent)
+            self.vte.set_background_transparent(background_transparent)
         else:
             dbg('setting background_transparent=False')
             self.vte.set_background_transparent(False)