[Qemu-devel] [PATCH 6/8] gtk: add support for screen scaling and full screen (v2)

[Anthony Liguori <aliguori@us.ibm.com>]

Basic menu items to enter full screen mode and zoom in/out.  Unlike SDL, we
don't allow arbitrary scaling based on window resizing.  The current behavior
with SDL causes a lot of problems for me.

Sometimes I accidentally resize the window a tiny bit while trying to move it
(Ubuntu's 1-pixel window decorations don't help here).  After that, scaling is
now active and if the screen changes size again, badness ensues since the
aspect ratio is skewed.

Allowing zooming by 25% in and out should cover most use cases.  We can add a
more flexible scaling later but for now, I think this is a more friendly
behavior.

Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
---
v1 -> v2
 - fix scaling (Paolo)
 - use ctrl-alt-+ instead of ctrl-alt-= for zoom
---
 ui/gtk.c |   92 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 files changed, 88 insertions(+), 4 deletions(-)

diff --git a/ui/gtk.c b/ui/gtk.c
index 0dac807..578cb94 100644
--- a/ui/gtk.c
+++ b/ui/gtk.c
@@ -79,6 +79,9 @@ typedef struct GtkDisplayState
 
     GtkWidget *view_menu_item;
     GtkWidget *view_menu;
+    GtkWidget *full_screen_item;
+    GtkWidget *zoom_in_item;
+    GtkWidget *zoom_out_item;
     GtkWidget *grab_item;
     GtkWidget *vga_item;
 
@@ -99,6 +102,7 @@ typedef struct GtkDisplayState
 
     double scale_x;
     double scale_y;
+    gboolean full_screen;
 
     GdkCursor *null_cursor;
     Notifier mouse_mode_notifier;
@@ -123,7 +127,7 @@ static void gd_update_cursor(GtkDisplayState *s, gboolean override)
     on_vga = (gtk_notebook_get_current_page(GTK_NOTEBOOK(s->notebook)) == 0);
 
     if ((override || on_vga) &&
-        (kbd_mouse_is_absolute() || gd_is_grab_active(s))) {
+        (s->full_screen || kbd_mouse_is_absolute() || gd_is_grab_active(s))) {
 	gdk_window_set_cursor(window, s->null_cursor);
     } else {
 	gdk_window_set_cursor(window, NULL);
@@ -215,9 +219,11 @@ static void gd_resize(DisplayState *ds)
                                                      ds->surface->height,
                                                      ds->surface->linesize);
 
-    gtk_widget_set_size_request(s->drawing_area,
-                                ds->surface->width * s->scale_x,
-                                ds->surface->height * s->scale_y);
+    if (!s->full_screen) {
+        gtk_widget_set_size_request(s->drawing_area,
+                                    ds->surface->width * s->scale_x,
+                                    ds->surface->height * s->scale_y);
+    }
 }
 
 /** QEMU Events **/
@@ -474,6 +480,54 @@ static void gd_menu_show_tabs(GtkMenuItem *item, void *opaque)
     }
 }
 
+static void gd_menu_full_screen(GtkMenuItem *item, void *opaque)
+{
+    GtkDisplayState *s = opaque;
+
+    if (gtk_check_menu_item_get_active(GTK_CHECK_MENU_ITEM(s->full_screen_item))) {
+        gtk_notebook_set_show_tabs(GTK_NOTEBOOK(s->notebook), FALSE);
+        gtk_widget_set_size_request(s->menu_bar, 0, 0);
+        gtk_widget_set_size_request(s->drawing_area, -1, -1);
+        gtk_window_set_resizable(GTK_WINDOW(s->window), TRUE);
+        gtk_window_fullscreen(GTK_WINDOW(s->window));
+        gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item), TRUE);
+        s->full_screen = TRUE;
+    } else {
+        gtk_window_unfullscreen(GTK_WINDOW(s->window));
+        gd_menu_show_tabs(GTK_MENU_ITEM(s->show_tabs_item), s);
+        gtk_widget_set_size_request(s->menu_bar, -1, -1);
+        gtk_widget_set_size_request(s->drawing_area, s->ds->surface->width, s->ds->surface->height);
+        gtk_window_set_resizable(GTK_WINDOW(s->window), FALSE);
+        gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item), FALSE);
+        s->full_screen = FALSE;
+    }
+
+    gd_update_cursor(s, FALSE);
+}
+
+static void gd_menu_zoom_in(GtkMenuItem *item, void *opaque)
+{
+    GtkDisplayState *s = opaque;
+
+    s->scale_x += .25;
+    s->scale_y += .25;
+
+    gd_resize(s->ds);
+}
+
+static void gd_menu_zoom_out(GtkMenuItem *item, void *opaque)
+{
+    GtkDisplayState *s = opaque;
+
+    s->scale_x -= .25;
+    s->scale_y -= .25;
+
+    s->scale_x = MAX(s->scale_x, .25);
+    s->scale_y = MAX(s->scale_y, .25);
+
+    gd_resize(s->ds);
+}
+
 static void gd_menu_grab_input(GtkMenuItem *item, void *opaque)
 {
     GtkDisplayState *s = opaque;
@@ -523,6 +577,9 @@ static void gd_change_page(GtkNotebook *nb, gpointer arg1, guint arg2,
     if (!on_vga) {
         gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item),
                                        FALSE);
+    } else if (s->full_screen) {
+        gtk_check_menu_item_set_active(GTK_CHECK_MENU_ITEM(s->grab_item),
+                                       TRUE);
     }
 
     if (arg2 == 0) {
@@ -690,6 +747,12 @@ static void gd_connect_signals(GtkDisplayState *s)
 
     g_signal_connect(s->quit_item, "activate",
                      G_CALLBACK(gd_menu_quit), s);
+    g_signal_connect(s->full_screen_item, "activate",
+                     G_CALLBACK(gd_menu_full_screen), s);
+    g_signal_connect(s->zoom_in_item, "activate",
+                     G_CALLBACK(gd_menu_zoom_in), s);
+    g_signal_connect(s->zoom_out_item, "activate",
+                     G_CALLBACK(gd_menu_zoom_out), s);
     g_signal_connect(s->vga_item, "activate",
                      G_CALLBACK(gd_menu_switch_vc), s);
     g_signal_connect(s->grab_item, "activate",
@@ -721,6 +784,27 @@ static void gd_create_menus(GtkDisplayState *s)
     gtk_menu_set_accel_group(GTK_MENU(s->view_menu), accel_group);
     s->view_menu_item = gtk_menu_item_new_with_mnemonic("_View");
 
+    s->full_screen_item = gtk_check_menu_item_new_with_mnemonic("_Full Screen");
+    gtk_menu_item_set_accel_path(GTK_MENU_ITEM(s->full_screen_item),
+                                 "<QEMU>/View/Full Screen");
+    gtk_accel_map_add_entry("<QEMU>/View/Full Screen", GDK_KEY_f, GDK_CONTROL_MASK | GDK_MOD1_MASK);
+    gtk_menu_append(GTK_MENU(s->view_menu), s->full_screen_item);
+
+    separator = gtk_separator_menu_item_new();
+    gtk_menu_append(GTK_MENU(s->view_menu), separator);
+
+    s->zoom_in_item = gtk_image_menu_item_new_from_stock(GTK_STOCK_ZOOM_IN, NULL);
+    gtk_menu_item_set_accel_path(GTK_MENU_ITEM(s->zoom_in_item),
+                                 "<QEMU>/View/Zoom In");
+    gtk_accel_map_add_entry("<QEMU>/View/Zoom In", GDK_KEY_plus, GDK_CONTROL_MASK | GDK_MOD1_MASK);
+    gtk_menu_append(GTK_MENU(s->view_menu), s->zoom_in_item);
+
+    s->zoom_out_item = gtk_image_menu_item_new_from_stock(GTK_STOCK_ZOOM_OUT, NULL);
+    gtk_menu_item_set_accel_path(GTK_MENU_ITEM(s->zoom_out_item),
+                                 "<QEMU>/View/Zoom Out");
+    gtk_accel_map_add_entry("<QEMU>/View/Zoom Out", GDK_KEY_minus, GDK_CONTROL_MASK | GDK_MOD1_MASK);
+    gtk_menu_append(GTK_MENU(s->view_menu), s->zoom_out_item);
+
     separator = gtk_separator_menu_item_new();
     gtk_menu_append(GTK_MENU(s->view_menu), separator);
 
-- 
1.7.4.1