Add API for getting properties of the ClutterBackend

Add functions to retrieve some of the properties of the screen used by
the backend, like its dimensions (also physical, in millimeters); the
number of screens. Also add setters and getters for the double click
time (in milliseconds) and distance.

clutter/clutter-backend.c

@@ -224,3 +224,85 @@ clutter_backend_put_event (ClutterBackend *backend,
 
   _clutter_event_queue_push (backend, clutter_event_copy (event));
 }
+
+gint
+clutter_backend_get_width (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), -1);
+
+  return backend->res_width;
+}
+
+gint
+clutter_backend_get_height (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), -1);
+
+  return backend->res_height;
+}
+
+gint
+clutter_backend_get_width_mm (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), -1);
+
+  return backend->mm_width;
+}
+
+gint
+clutter_backend_get_height_mm (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), -1);
+
+  return backend->mm_height;
+}
+
+gint
+clutter_backend_get_screen_number (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), -1);
+
+  return backend->screen_n;
+}
+
+gdouble
+clutter_backend_get_resolution (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), 0.0);
+
+  return (gdouble) backend->res_width / (gdouble) backend->res_height;
+}
+
+void
+clutter_backend_set_double_click_time (ClutterBackend *backend,
+                                       guint           msec)
+{
+  g_return_if_fail (CLUTTER_IS_BACKEND (backend));
+
+  backend->double_click_time = msec;
+}
+
+guint
+clutter_backend_get_double_click_time (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), 0);
+
+  return backend->double_click_time;
+}
+
+void
+clutter_backend_set_double_click_distance (ClutterBackend *backend,
+                                           guint           distance)
+{
+  g_return_if_fail (CLUTTER_IS_BACKEND (backend));
+  
+  backend->double_click_distance = distance;
+}
+
+guint
+clutter_backend_get_double_click_distance (ClutterBackend *backend)
+{
+  g_return_val_if_fail (CLUTTER_IS_BACKEND (backend), 0);
+
+  return backend->double_click_distance;
+}

clutter/clutter-backend.h

@@ -47,6 +47,12 @@ struct _ClutterBackend
   GObject parent_instance;
 
   /*< private >*/
+  gint mm_width;
+  gint mm_height;
+  gint res_width;
+  gint res_height;
+
+  gint screen_n;
 
   /* events queue: every backend must implement one */
   GQueue *events_queue;
@@ -90,6 +96,19 @@ ClutterEvent *  clutter_backend_peek_event  (ClutterBackend *backend);
 void          clutter_backend_put_event  (ClutterBackend *backend,
                                           ClutterEvent   *event);
 
+gint clutter_backend_get_width         (ClutterBackend *backend);
+gint clutter_backend_get_height        (ClutterBackend *backend);
+gint clutter_backend_get_width_mm      (ClutterBackend *backend);
+gint clutter_backend_get_height_mm     (ClutterBackend *backend);
+gint clutter_backend_get_screen_number (ClutterBackend *backend);
+
+void  clutter_backend_set_double_click_time     (ClutterBackend *backend,
+                                                 guint           msec);
+guint clutter_backend_get_double_click_time     (ClutterBackend *backend);
+void  clutter_backend_set_double_click_distance (ClutterBackend *backend,
+                                                 guint           distance);
+guint clutter_backend_get_double_click_distance (ClutterBackend *backend);
+
 G_END_DECLS
 
 #endif /* __CLUTTER_BACKEND_H__ */

clutter/glx/clutter-backend-glx.c

@@ -95,19 +95,24 @@ clutter_backend_glx_post_parse (ClutterBackend  *backend,
       CLUTTER_NOTE (MISC, "Getting the X screen");
 
       if (clutter_screen == 0)
-        backend_glx->xscreen = DefaultScreen (backend_glx->xdpy);
+        backend_glx->xscreen = DefaultScreenOfDisplay (backend_glx->xdpy);
       else
-        {
+        backend_glx->xscreen = ScreenOfDisplay (backend_glx->xdpy,
-          Screen *xscreen;
+                                                clutter_screen);
       
-          xscreen = ScreenOfDisplay (backend_glx->xdpy, clutter_screen);
+      backend_glx->xscreen_num = XScreenNumberOfScreen (backend_glx->xscreen);
-          backend_glx->xscreen = XScreenNumberOfScreen (xscreen);
-        }
 
       backend_glx->xwin_root = RootWindow (backend_glx->xdpy,
-                                           backend_glx->xscreen);
+                                           backend_glx->xscreen_num);
       
       backend_glx->display_name = g_strdup (clutter_display_name);
+
+      /* generic backend properties */
+      backend->res_width = WidthOfScreen (backend_glx->xscreen);
+      backend->res_height = HeightOfScreen (backend_glx->xscreen);
+      backend->mm_width = WidthMMOfScreen (backend_glx->xscreen);
+      backend->mm_height = HeightMMOfScreen (backend_glx->xscreen);
+      backend->screen_n = ScreenCount (backend_glx->xdpy);
     }
 
   g_free (clutter_display_name);
@@ -115,7 +120,7 @@ clutter_backend_glx_post_parse (ClutterBackend  *backend,
   CLUTTER_NOTE (MISC, "X Display `%s' [%p] opened (screen:%d, root:%u)",
                 backend_glx->display_name,
                 backend_glx->xdpy,
-                backend_glx->xscreen,
+                backend_glx->xscreen_num,
                 (unsigned int) backend_glx->xwin_root);
 
   return TRUE;
@@ -146,7 +151,7 @@ clutter_backend_glx_init_stage (ClutterBackend  *backend,
       stage_glx = CLUTTER_STAGE_GLX (stage);
       stage_glx->xdpy = backend_glx->xdpy;
       stage_glx->xwin_root = backend_glx->xwin_root;
-      stage_glx->xscreen = backend_glx->xscreen;
+      stage_glx->xscreen = backend_glx->xscreen_num;
 
       CLUTTER_NOTE (MISC, "GLX stage created (display:%p, screen:%d, root:%u)",
                     stage_glx->xdpy,
@@ -302,6 +307,10 @@ clutter_backend_glx_init (ClutterBackendGlx *backend_glx)
   backend->button_x[0] = backend->button_x[1] = 0;
   backend->button_y[0] = backend->button_y[1] = 0;
 
+  backend->res_width = backend->res_height = -1;
+  backend->mm_width = backend->mm_height = -1;
+  backend->screen_n = 0;
+
   /* FIXME - find a way to set this stuff from XSettings */
   backend->double_click_time = 250;
   backend->double_click_distance = 5;
@@ -392,7 +401,7 @@ clutter_glx_get_default_screen (void)
       return -1;
     }
 
-  return backend_singleton->xscreen;
+  return backend_singleton->xscreen_num;
 }
 
 /**
@@ -415,5 +424,3 @@ clutter_glx_get_root_window (void)
 
   return backend_singleton->xwin_root;
 }
-
-

clutter/glx/clutter-backend-glx.h

@@ -48,7 +48,8 @@ struct _ClutterBackendGlx
 
   Display *xdpy;
   Window xwin_root;
-  int xscreen;
+  Screen *xscreen;
+  int xscreen_num;
   gchar *display_name;
 
   /* main stage singleton */