Stop moving stuff onscreen when the screen size changes
[mikachu/openbox.git] / openbox / screen.c
index 5246d34..a6551cf 100644 (file)
@@ -38,7 +38,6 @@
 #include "obt/display.h"
 #include "obt/xqueue.h"
 #include "obt/prop.h"
-#include "obt/mainloop.h"
 
 #include <X11/Xlib.h>
 #ifdef HAVE_UNISTD_H
 
 static gboolean screen_validate_layout(ObDesktopLayout *l);
 static gboolean replace_wm(void);
-static void     screen_tell_ksplash(void);
+//static void     screen_tell_ksplash(void);
 static void     screen_fallback_focus(void);
 
-guint           screen_num_desktops;
-guint           screen_num_monitors;
-guint           screen_desktop;
-guint           screen_last_desktop;
-gboolean        screen_showing_desktop;
-ObDesktopLayout screen_desktop_layout;
-gchar         **screen_desktop_names;
-Window          screen_support_win;
-Time            screen_desktop_user_time = CurrentTime;
+guint                  screen_num_desktops;
+guint                  screen_num_monitors;
+guint                  screen_desktop;
+guint                  screen_last_desktop;
+ObScreenShowDestopMode screen_show_desktop_mode;
+ObDesktopLayout        screen_desktop_layout;
+gchar                **screen_desktop_names;
+Window                 screen_support_win;
+Time                   screen_desktop_user_time = CurrentTime;
 
 static Size     screen_physical_size;
 static guint    screen_old_desktop;
 static gboolean screen_desktop_timeout = TRUE;
+static guint    screen_desktop_timer = 0;
 /*! An array of desktops, holding an array of areas per monitor */
 static Rect  *monitor_area = NULL;
 /*! An array of desktops, holding an array of struts */
@@ -80,11 +80,12 @@ static GSList *struts_right = NULL;
 static GSList *struts_bottom = NULL;
 
 static ObPagerPopup *desktop_popup;
+static guint         desktop_popup_timer = 0;
 static gboolean      desktop_popup_perm;
 
 /*! The number of microseconds that you need to be on a desktop before it will
   replace the remembered "last desktop" */
-#define REMEMBER_LAST_DESKTOP_TIME 750000
+#define REMEMBER_LAST_DESKTOP_TIME 750
 
 static gboolean replace_wm(void)
 {
@@ -168,7 +169,7 @@ gboolean screen_annex(void)
 
     /* create the netwm support window */
     attrib.override_redirect = TRUE;
-    attrib.event_mask = PropertyChangeMask;
+    attrib.event_mask = PropertyChangeMask | KeyPressMask | KeyReleaseMask;
     screen_support_win = XCreateWindow(obt_display, obt_root(ob_screen),
                                        -100, -100, 1, 1, 0,
                                        CopyFromParent, InputOutput,
@@ -205,7 +206,7 @@ gboolean screen_annex(void)
                    NET_SUPPORTING_WM_CHECK, WINDOW, screen_support_win);
 
     /* set properties on the supporting window */
-    OBT_PROP_SETS(screen_support_win, NET_WM_NAME, utf8, "Openbox");
+    OBT_PROP_SETS(screen_support_win, NET_WM_NAME, "Openbox");
     OBT_PROP_SET32(screen_support_win, NET_SUPPORTING_WM_CHECK,
                    WINDOW, screen_support_win);
 
@@ -248,6 +249,7 @@ gboolean screen_annex(void)
     supported[i++] = OBT_PROP_ATOM(NET_WM_WINDOW_TYPE_DIALOG);
     supported[i++] = OBT_PROP_ATOM(NET_WM_WINDOW_TYPE_NORMAL);
     supported[i++] = OBT_PROP_ATOM(NET_WM_ALLOWED_ACTIONS);
+    supported[i++] = OBT_PROP_ATOM(NET_WM_WINDOW_OPACITY);
     supported[i++] = OBT_PROP_ATOM(NET_WM_ACTION_MOVE);
     supported[i++] = OBT_PROP_ATOM(NET_WM_ACTION_RESIZE);
     supported[i++] = OBT_PROP_ATOM(NET_WM_ACTION_MINIMIZE);
@@ -292,17 +294,21 @@ gboolean screen_annex(void)
     supported[i++] = OBT_PROP_ATOM(KDE_NET_WM_FRAME_STRUT);
     supported[i++] = OBT_PROP_ATOM(KDE_NET_WM_WINDOW_TYPE_OVERRIDE);
 
+    supported[i++] = OBT_PROP_ATOM(OB_FOCUS);
     supported[i++] = OBT_PROP_ATOM(OB_WM_ACTION_UNDECORATE);
     supported[i++] = OBT_PROP_ATOM(OB_WM_STATE_UNDECORATED);
     supported[i++] = OBT_PROP_ATOM(OPENBOX_PID);
     supported[i++] = OBT_PROP_ATOM(OB_THEME);
     supported[i++] = OBT_PROP_ATOM(OB_CONFIG_FILE);
+    supported[i++] = OBT_PROP_ATOM(OB_LAST_DESKTOP);
     supported[i++] = OBT_PROP_ATOM(OB_CONTROL);
     supported[i++] = OBT_PROP_ATOM(OB_VERSION);
     supported[i++] = OBT_PROP_ATOM(OB_APP_ROLE);
     supported[i++] = OBT_PROP_ATOM(OB_APP_TITLE);
     supported[i++] = OBT_PROP_ATOM(OB_APP_NAME);
     supported[i++] = OBT_PROP_ATOM(OB_APP_CLASS);
+    supported[i++] = OBT_PROP_ATOM(OB_APP_GROUP_NAME);
+    supported[i++] = OBT_PROP_ATOM(OB_APP_GROUP_CLASS);
     supported[i++] = OBT_PROP_ATOM(OB_APP_TYPE);
     g_assert(i == num_support);
 
@@ -310,14 +316,14 @@ gboolean screen_annex(void)
                     NET_SUPPORTED, ATOM, supported, num_support);
     g_free(supported);
 
-    OBT_PROP_SETS(RootWindow(obt_display, ob_screen), OB_VERSION, utf8,
+    OBT_PROP_SETS(RootWindow(obt_display, ob_screen), OB_VERSION,
                   OPENBOX_VERSION);
 
-    screen_tell_ksplash();
+    //screen_tell_ksplash();
 
     return TRUE;
 }
-
+#if 0
 static void screen_tell_ksplash(void)
 {
     XEvent e;
@@ -351,7 +357,7 @@ static void screen_tell_ksplash(void)
     XSendEvent(obt_display, obt_root(ob_screen),
                False, SubstructureNotifyMask, &e);
 }
-
+#endif
 void screen_startup(gboolean reconfig)
 {
     gchar **names = NULL;
@@ -374,7 +380,7 @@ void screen_startup(gboolean reconfig)
     screen_resize();
 
     /* have names already been set for the desktops? */
-    if (OBT_PROP_GETSS(obt_root(ob_screen), NET_DESKTOP_NAMES, utf8, &names)) {
+    if (OBT_PROP_GETSS_UTF8(obt_root(ob_screen), NET_DESKTOP_NAMES, &names)) {
         g_strfreev(names);
         namesexist = TRUE;
     }
@@ -396,7 +402,7 @@ void screen_startup(gboolean reconfig)
 
         /* set the root window property */
         OBT_PROP_SETSS(obt_root(ob_screen),
-                       NET_DESKTOP_NAMES, utf8, (const gchar**)names);
+                       NET_DESKTOP_NAMES, (const gchar*const*)names);
 
         g_strfreev(names);
     }
@@ -438,12 +444,16 @@ void screen_startup(gboolean reconfig)
     else
         screen_set_desktop(MIN(config_screen_firstdesk,
                                screen_num_desktops) - 1, FALSE);
-    screen_last_desktop = screen_desktop;
+    OBT_PROP_GET32(obt_root(ob_screen), OB_LAST_DESKTOP, CARDINAL, &screen_last_desktop);
+    if (screen_last_desktop < 0 || screen_last_desktop >= screen_num_desktops) {
+        screen_last_desktop = screen_desktop;
+        OBT_PROP_SET32(obt_root(ob_screen), OB_LAST_DESKTOP, CARDINAL, screen_last_desktop);
+    }
 
     /* don't start in showing-desktop mode */
-    screen_showing_desktop = FALSE;
+    screen_show_desktop_mode = SCREEN_SHOW_DESKTOP_NO;
     OBT_PROP_SET32(obt_root(ob_screen),
-                   NET_SHOWING_DESKTOP, CARDINAL, screen_showing_desktop);
+                   NET_SHOWING_DESKTOP, CARDINAL, screen_showing_desktop());
 
     if (session_desktop_layout_present &&
         screen_validate_layout(&session_desktop_layout))
@@ -478,7 +488,6 @@ void screen_shutdown(gboolean reconfig)
 
 void screen_resize(void)
 {
-    static gint oldw = 0, oldh = 0;
     gint w, h;
     GList *it;
     gulong geometry[2];
@@ -486,10 +495,6 @@ void screen_resize(void)
     w = WidthOfScreen(ScreenOfDisplay(obt_display, ob_screen));
     h = HeightOfScreen(ScreenOfDisplay(obt_display, ob_screen));
 
-    if (w == oldw && h == oldh) return;
-
-    oldw = w; oldh = h;
-
     /* Set the _NET_DESKTOP_GEOMETRY hint */
     screen_physical_size.width = geometry[0] = w;
     screen_physical_size.height = geometry[1] = h;
@@ -499,11 +504,14 @@ void screen_resize(void)
     if (ob_state() != OB_STATE_RUNNING)
         return;
 
-    screen_update_areas();
+    /* this calls screen_update_areas(), which we need ! */
     dock_configure();
 
-    for (it = client_list; it; it = g_list_next(it))
-        client_move_onscreen(it->data, FALSE);
+    // bug: this is done in screen_update_areas() already
+//    for (it = client_list; it; it = g_list_next(it)) {
+//        client_move_onscreen(it->data, FALSE);
+//        client_reconfigure(it->data, FALSE);
+//    }
 }
 
 void screen_set_num_desktops(guint num)
@@ -601,7 +609,9 @@ static void screen_fallback_focus(void)
 static gboolean last_desktop_func(gpointer data)
 {
     screen_desktop_timeout = TRUE;
-    return FALSE;
+    OBT_PROP_SET32(obt_root(ob_screen), OB_LAST_DESKTOP, CARDINAL, screen_last_desktop);
+    screen_desktop_timer = 0;
+    return FALSE; /* don't repeat */
 }
 
 void screen_set_desktop(guint num, gboolean dofocus)
@@ -683,9 +693,9 @@ void screen_set_desktop(guint num, gboolean dofocus)
         }
     }
     screen_desktop_timeout = FALSE;
-    obt_main_loop_timeout_remove(ob_main_loop, last_desktop_func);
-    obt_main_loop_timeout_add(ob_main_loop, REMEMBER_LAST_DESKTOP_TIME,
-                              last_desktop_func, NULL, NULL, NULL);
+    if (screen_desktop_timer) g_source_remove(screen_desktop_timer);
+    screen_desktop_timer = g_timeout_add(REMEMBER_LAST_DESKTOP_TIME,
+                                         last_desktop_func, NULL);
 
     ob_debug("Moving to desktop %d", num+1);
 
@@ -937,6 +947,7 @@ static guint translate_row_col(guint r, guint c)
 static gboolean hide_desktop_popup_func(gpointer data)
 {
     pager_popup_hide(desktop_popup);
+    desktop_popup_timer = 0;
     return FALSE; /* don't repeat */
 }
 
@@ -959,21 +970,21 @@ void screen_show_desktop_popup(guint d, gboolean perm)
                           MAX(a->width/3, POPUP_WIDTH));
     pager_popup_show(desktop_popup, screen_desktop_names[d], d);
 
-    obt_main_loop_timeout_remove(ob_main_loop, hide_desktop_popup_func);
+    if (desktop_popup_timer) g_source_remove(desktop_popup_timer);
+    desktop_popup_timer = 0;
     if (!perm && !desktop_popup_perm)
         /* only hide if its not already being show permanently */
-        obt_main_loop_timeout_add(ob_main_loop,
-                                  config_desktop_popup_time * 1000,
-                                  hide_desktop_popup_func, desktop_popup,
-                                  g_direct_equal, NULL);
+        desktop_popup_timer = g_timeout_add(config_desktop_popup_time,
+                                            hide_desktop_popup_func,
+                                            desktop_popup);
     if (perm)
         desktop_popup_perm = TRUE;
 }
 
 void screen_hide_desktop_popup(void)
 {
-    obt_main_loop_timeout_remove_data(ob_main_loop, hide_desktop_popup_func,
-                                      desktop_popup, FALSE);
+    if (desktop_popup_timer) g_source_remove(desktop_popup_timer);
+    desktop_popup_timer = 0;
     pager_popup_hide(desktop_popup);
     desktop_popup_perm = FALSE;
 }
@@ -1179,7 +1190,7 @@ void screen_update_desktop_names(void)
     screen_desktop_names = NULL;
 
     if (OBT_PROP_GETSS(obt_root(ob_screen),
-                       NET_DESKTOP_NAMES, utf8, &screen_desktop_names))
+                       NET_DESKTOP_NAMES, &screen_desktop_names))
         for (i = 0; screen_desktop_names[i] && i < screen_num_desktops; ++i);
     else
         i = 0;
@@ -1206,7 +1217,7 @@ void screen_update_desktop_names(void)
         /* if we changed any names, then set the root property so we can
            all agree on the names */
         OBT_PROP_SETSS(obt_root(ob_screen), NET_DESKTOP_NAMES,
-                       utf8, (const gchar**)screen_desktop_names);
+                       (const gchar*const*)screen_desktop_names);
     }
 
     /* resize the pager for these names */
@@ -1215,15 +1226,33 @@ void screen_update_desktop_names(void)
                                       screen_num_desktops);
 }
 
-void screen_show_desktop(gboolean show, ObClient *show_only)
+void screen_show_desktop(ObScreenShowDestopMode show_mode, ObClient *show_only)
 {
     GList *it;
 
-    if (show == screen_showing_desktop) return; /* no change */
+    ObScreenShowDestopMode before_mode = screen_show_desktop_mode;
 
-    screen_showing_desktop = show;
+    gboolean showing_before = screen_showing_desktop();
+    screen_show_desktop_mode = show_mode;
+    gboolean showing_after = screen_showing_desktop();
 
-    if (show) {
+    if (showing_before == showing_after) {
+        /* No change. */
+        screen_show_desktop_mode = before_mode;
+        return;
+    }
+
+    if (screen_show_desktop_mode == SCREEN_SHOW_DESKTOP_UNTIL_TOGGLE &&
+        show_only != NULL)
+    {
+        /* If we're showing the desktop until the show-mode is toggled, we
+           don't allow breaking out of showing-desktop mode unless we're
+           showing all the windows again. */
+        screen_show_desktop_mode = before_mode;
+        return;
+    }
+
+    if (showing_after) {
         /* hide windows bottom to top */
         for (it = g_list_last(stacking_list); it; it = g_list_previous(it)) {
             if (WINDOW_IS_CLIENT(it->data)) {
@@ -1247,7 +1276,7 @@ void screen_show_desktop(gboolean show, ObClient *show_only)
         }
     }
 
-    if (show) {
+    if (showing_after) {
         /* focus the desktop */
         for (it = focus_order; it; it = g_list_next(it)) {
             ObClient *c = it->data;
@@ -1272,8 +1301,23 @@ void screen_show_desktop(gboolean show, ObClient *show_only)
         }
     }
 
-    show = !!show; /* make it boolean */
-    OBT_PROP_SET32(obt_root(ob_screen), NET_SHOWING_DESKTOP, CARDINAL, show);
+    OBT_PROP_SET32(obt_root(ob_screen),
+                   NET_SHOWING_DESKTOP,
+                   CARDINAL,
+                   !!showing_after);
+}
+
+gboolean screen_showing_desktop()
+{
+    switch (screen_show_desktop_mode) {
+    case SCREEN_SHOW_DESKTOP_NO:
+        return FALSE;
+    case SCREEN_SHOW_DESKTOP_UNTIL_WINDOW:
+    case SCREEN_SHOW_DESKTOP_UNTIL_TOGGLE:
+        return TRUE;
+    }
+    g_assert_not_reached();
+    return FALSE;
 }
 
 void screen_install_colormap(ObClient *client, gboolean install)
@@ -1324,8 +1368,9 @@ typedef struct {
 static void get_xinerama_screens(Rect **xin_areas, guint *nxin)
 {
     guint i;
-    gint n, l, r, t, b;
+    gint l, r, t, b;
 #ifdef XINERAMA
+    gint n;
     XineramaScreenInfo *info;
 #endif
 
@@ -1368,13 +1413,28 @@ static void get_xinerama_screens(Rect **xin_areas, guint *nxin)
         b = MAX(b, (*xin_areas)[i].y + (*xin_areas)[i].height - 1);
     }
     RECT_SET((*xin_areas)[*nxin], l, t, r - l + 1, b - t + 1);
+
+    for (i = 0; i < *nxin; ++i)
+        ob_debug("Monitor %d @ %d,%d %dx%d\n", i,
+                 (*xin_areas)[i].x, (*xin_areas)[i].y,
+                 (*xin_areas)[i].width, (*xin_areas)[i].height);
+    ob_debug("Full desktop @ %d,%d %dx%d\n",
+             (*xin_areas)[i].x, (*xin_areas)[i].y,
+             (*xin_areas)[i].width, (*xin_areas)[i].height);
 }
 
 void screen_update_areas(void)
 {
     guint i;
     gulong *dims;
-    GList *it;
+    GList *it, *onscreen;
+
+    /* collect the clients that are on screen */
+    onscreen = NULL;
+    for (it = client_list; it; it = g_list_next(it)) {
+        if (client_monitor(it->data) != screen_num_monitors)
+            onscreen = g_list_prepend(onscreen, it->data);
+    }
 
     g_free(monitor_area);
     get_xinerama_screens(&monitor_area, &screen_num_monitors);
@@ -1448,7 +1508,7 @@ void screen_update_areas(void)
                     dims, 4 * screen_num_desktops);
 
     /* the area has changed, adjust all the windows if they need it */
-    for (it = client_list; it; it = g_list_next(it))
+    for (it = onscreen; it; it = g_list_next(it))
         client_reconfigure(it->data, FALSE);
 
     g_free(dims);
@@ -1620,28 +1680,153 @@ Rect* screen_area(guint desktop, guint head, Rect *search)
     return a;
 }
 
+typedef struct {
+    Rect r;
+    gboolean subtract;
+} RectArithmetic;
+
 guint screen_find_monitor(const Rect *search)
 {
     guint i;
-    guint most = screen_num_monitors;
-    guint mostv = 0;
+    guint mostpx_index = screen_num_monitors;
+    glong mostpx = 0;
+    guint closest_distance_index = screen_num_monitors;
+    guint closest_distance = G_MAXUINT;
+    GSList *counted = NULL;
+
+    /* we want to count the number of pixels search has on each monitor, but not
+       double count.  so if a pixel is counted on monitor A then we should not
+       count it again on monitor B. in the end we want to return the monitor
+       that had the most pixels counted under this scheme.
+
+       this assumes that monitors earlier in the list are more desirable to be
+       considered the search area's monitor.  we try the configured primary
+       monitor first, so it gets the highest preference.
+
+       if we have counted an area A, then we want to subtract the intersection
+       of A with the area on future monitors.
+       but now consider if we count an area B that intersects A. we want to
+       subtract the area B from that counted on future monitors, but not
+       subtract the intersection of A and B twice! so we would add the
+       intersection of A and B back, to account for it being subtracted both
+       for A and B.
+
+       this is the idea behind the algorithm.  we always subtract the full area
+       for monitor M intersected with the search area. we'll call that AREA.
+       but then we go through the list |counted| and for each rectangle in
+       the list that is being subtracted from future monitors, we insert a
+       request to add back the intersection of the subtracted rect with AREA.
+       vice versa for a rect in |counted| that is getting added back.
+    */
+
+    if (config_primary_monitor_index < screen_num_monitors) {
+        const Rect *monitor;
+        Rect on_current_monitor;
+        glong area;
+
+        monitor = screen_physical_area_monitor(config_primary_monitor_index);
+
+        if (RECT_INTERSECTS_RECT(*monitor, *search)) {
+            RECT_SET_INTERSECTION(on_current_monitor, *monitor, *search);
+            area = RECT_AREA(on_current_monitor);
+
+            if (area > mostpx) {
+                mostpx = area;
+                mostpx_index = config_primary_monitor_index;
+            }
+
+            /* add the intersection rect on the current monitor to the
+               counted list. that's easy for the first one, we just mark it for
+               subtraction */
+            {
+                RectArithmetic *ra = g_slice_new(RectArithmetic);
+                ra->r = on_current_monitor;
+                ra->subtract = TRUE;
+                counted = g_slist_prepend(counted, ra);
+            }
+        }
+    }
 
     for (i = 0; i < screen_num_monitors; ++i) {
-        const Rect *area = screen_physical_area_monitor(i);
-        if (RECT_INTERSECTS_RECT(*area, *search)) {
-            Rect r;
-            guint v;
+        const Rect *monitor;
+        Rect on_current_monitor;
+        glong area;
+        GSList *it;
 
-            RECT_SET_INTERSECTION(r, *area, *search);
-            v = r.width * r.height;
+        monitor = screen_physical_area_monitor(i);
 
-            if (v > mostv) {
-                mostv = v;
-                most = i;
+        if (!RECT_INTERSECTS_RECT(*monitor, *search)) {
+            /* If we don't intersect then find the distance between the search
+               rect and the monitor. We'll use the closest monitor from this
+               metric if none of the monitors intersect. */
+            guint distance = rect_manhatten_distance(*monitor, *search);
+
+            if (distance < closest_distance) {
+                closest_distance = distance;
+                closest_distance_index = i;
             }
+            continue;
+        }
+
+        if (i == config_primary_monitor_index)
+            continue;  /* already did this one */
+
+        RECT_SET_INTERSECTION(on_current_monitor, *monitor, *search);
+        area = RECT_AREA(on_current_monitor);
+
+        /* remove pixels we already counted on any previous monitors. */
+        for (it = counted; it; it = g_slist_next(it)) {
+            RectArithmetic *ra = it->data;
+            Rect intersection;
+
+            RECT_SET_INTERSECTION(intersection, ra->r, *search);
+            if (ra->subtract) area -= RECT_AREA(intersection);
+            else area += RECT_AREA(intersection);
+        }
+
+        if (area > mostpx) {
+            mostpx = area;
+            mostpx_index = i;
+        }
+
+        /* add the intersection rect on the current monitor I to the counted
+           list.
+           but now we need to compensate for every rectangle R already in the
+           counted list, and add a new rect R' that is the intersection of
+           R and I, but with the reverse subtraction/addition operation.
+        */
+        for (it = counted; it; it = g_slist_next(it)) {
+            RectArithmetic *saved = it->data;
+
+            if (!RECT_INTERSECTS_RECT(saved->r, on_current_monitor))
+                continue;
+            /* we are going to subtract our rect from future monitors, but
+               part of it may already be being subtracted/added, so compensate
+               to not double add/subtract. */
+            RectArithmetic *reverse = g_slice_new(RectArithmetic);
+            RECT_SET_INTERSECTION(reverse->r, saved->r, on_current_monitor);
+            reverse->subtract = !saved->subtract;
+            /* prepend so we can continue thru the list uninterupted */
+            counted = g_slist_prepend(counted, reverse);
+        }
+        {
+            RectArithmetic *ra = g_slice_new(RectArithmetic);
+            ra->r = on_current_monitor;
+            ra->subtract = TRUE;
+            counted = g_slist_prepend(counted, ra);
         }
     }
-    return most;
+
+    while (counted) {
+        g_slice_free(RectArithmetic, counted->data);
+        counted = g_slist_delete_link(counted, counted);
+    }
+
+    if (mostpx_index < screen_num_monitors)
+        return mostpx_index;
+
+    g_assert(closest_distance_index < screen_num_monitors);
+    return closest_distance_index;
 }
 
 const Rect* screen_physical_area_all_monitors(void)
@@ -1703,7 +1888,7 @@ void screen_set_root_cursor(void)
 {
     if (sn_app_starting())
         XDefineCursor(obt_display, obt_root(ob_screen),
-                      ob_cursor(OB_CURSOR_BUSYPOINTER));
+                      ob_cursor(OB_CURSOR_BUSY));
     else
         XDefineCursor(obt_display, obt_root(ob_screen),
                       ob_cursor(OB_CURSOR_POINTER));
@@ -1742,3 +1927,39 @@ gboolean screen_pointer_pos(gint *x, gint *y)
     }
     return ret;
 }
+
+gboolean screen_compare_desktops(guint a, guint b)
+{
+    if (a == DESKTOP_ALL)
+        a = screen_desktop;
+    if (b == DESKTOP_ALL)
+        b = screen_desktop;
+    return a == b;
+}
+
+void screen_apply_gravity_point(gint *x, gint *y, gint width, gint height,
+                                const GravityPoint *position, const Rect *area)
+{
+    if (position->x.center)
+        *x = area->width / 2 - width / 2;
+    else {
+        *x = position->x.pos;
+        if (position->x.denom)
+            *x = (*x * area->width) / position->x.denom;
+        if (position->x.opposite)
+            *x = area->width - width - *x;
+    }
+
+    if (position->y.center)
+        *y = area->height / 2 - height / 2;
+    else {
+        *y = position->y.pos;
+        if (position->y.denom)
+            *y = (*y * area->height) / position->y.denom;
+        if (position->y.opposite)
+            *y = area->height - height - *y;
+    }
+
+    *x += area->x;
+    *y += area->y;
+}