Do all display alignment in virt-viewer

Don't rely on spice-gtk to do any alignment of displays.  This patch sets the
disable-display-align property on the SpiceMainChannel, and makes the
VirtViewerSession in charge of doing all alignment. This means that every
display has to tell the VirtViewerSession when its "virtual monitor" has changed
configuration (and wants to reconfigure its display on the guest), rather than
sending it directly to the Main Channel.  The session will then align the
displays (if necessary), and the spice session will send down new configuration
for all displays at once. This solves a couple of problems:

1. It allows the session to send down absolute coordinates only in the case
   where *all* windows are fullscreen (so that we can still support
   vertically-stacked displays, etc).  But it auto-aligns displays if only a
   subset of the displays are in fullscreen mode. This solves the problem of
   overlapping regions on different displays when one monitor is in fullscreen
   because only one monitor's configuration was updated and the others were not
   aligned.
2. Allows us to always align based on the current position of each display. This
   contrasts with the earlier behavior where the position used for alignment was
   the window's position at the time when it was last resized. This caused
   displays to be arranged in a seemingly non-deterministic manner if one window
   was moved and then another window was resized (causing a display
   re-configuration).

Solves rhbz#1002156

1 files changed, 20 insertions, 5 deletions

diff --git a/src/virt-viewer-session-spice.c b/src/virt-viewer-session-spice.c
index 85d3895..d87fcd7 100644
--- a/src/virt-viewer-session-spice.c
+++ b/src/virt-viewer-session-spice.c
@@ -82,6 +82,7 @@ static void virt_viewer_session_spice_channel_destroy(SpiceSession *s,
 static void virt_viewer_session_spice_smartcard_insert(VirtViewerSession *session);
 static void virt_viewer_session_spice_smartcard_remove(VirtViewerSession *session);
 static gboolean virt_viewer_session_spice_fullscreen_auto_conf(VirtViewerSessionSpice *self);
+static void virt_viewer_session_spice_apply_monitor_geometry(VirtViewerSession *self, GdkRectangle *monitors, guint nmonitors);
 
 static void
 virt_viewer_session_spice_get_property(GObject *object, guint property_id,
@@ -157,6 +158,7 @@ virt_viewer_session_spice_class_init(VirtViewerSessionSpiceClass *klass)
     dclass->smartcard_insert = virt_viewer_session_spice_smartcard_insert;
     dclass->smartcard_remove = virt_viewer_session_spice_smartcard_remove;
     dclass->mime_type = virt_viewer_session_spice_mime_type;
+    dclass->apply_monitor_geometry = virt_viewer_session_spice_apply_monitor_geometry;
 
     g_type_class_add_private(klass, sizeof(VirtViewerSessionSpicePrivate));
 
@@ -675,6 +677,10 @@ virt_viewer_session_spice_channel_new(SpiceSession *s,
         g_signal_connect(channel, "channel-event",
                          G_CALLBACK(virt_viewer_session_spice_main_channel_event), self);
         self->priv->main_channel = SPICE_MAIN_CHANNEL(channel);
+        g_object_set(G_OBJECT(channel),
+                     "disable-display-position", FALSE,
+                     "disable-display-align", TRUE,
+                     NULL);
 
         g_signal_connect(channel, "notify::agent-connected", G_CALLBACK(agent_connected_changed), self);
     }
@@ -752,11 +758,6 @@ virt_viewer_session_spice_fullscreen_auto_conf(VirtViewerSessionSpice *self)
         return FALSE;
     }
 
-
-    g_object_set(G_OBJECT(cmain),
-                 "disable-display-position", FALSE,
-                 "disable-display-align", TRUE,
-                 NULL);
     spice_main_set_display_enabled(cmain, -1, FALSE);
 
     ndisplays = virt_viewer_app_get_n_initial_displays(app);
@@ -887,6 +888,20 @@ virt_viewer_session_spice_smartcard_remove(VirtViewerSession *session G_GNUC_UNU
     spice_smartcard_manager_remove_card(spice_smartcard_manager_get());
 }
 
+void
+virt_viewer_session_spice_apply_monitor_geometry(VirtViewerSession *session, GdkRectangle *monitors, guint nmonitors)
+{
+    guint i;
+    VirtViewerSessionSpice *self = VIRT_VIEWER_SESSION_SPICE(session);
+
+    for (i = 0; i < nmonitors; i++) {
+        GdkRectangle* rect = &monitors[i];
+
+        spice_main_set_display(self->priv->main_channel, i, rect->x,
+                               rect->y, rect->width, rect->height);
+    }
+}
+
 /*
  * Local variables:
  *  c-indent-level: 4