[gnome-settings-daemon/randr-hotplug: 10/13] Implement autoconfiguration of the outputs

[Federico Mena Quintero <federico src gnome org>]

commit be513b3c7d80d0b7013d79ce46d7eeca929705cc
Author: Federico Mena Quintero <federico novell com>
Date:   Sun May 31 13:56:37 2009 -0500

    Implement autoconfiguration of the outputs
    
    This is similar in spirit to 'xrandr --auto', but we disfavor selecting clone modes.
    Instead, we lay out the outputs left-to-right.
    
    Signed-off-by: Federico Mena Quintero <federico novell com>
---
 plugins/xrandr/gsd-xrandr-manager.c |   96 ++++++++++++++++++++++++++++++++++-
 1 files changed, 95 insertions(+), 1 deletions(-)

diff --git a/plugins/xrandr/gsd-xrandr-manager.c b/plugins/xrandr/gsd-xrandr-manager.c
index cd8e5c3..f4e18ed 100644
--- a/plugins/xrandr/gsd-xrandr-manager.c
+++ b/plugins/xrandr/gsd-xrandr-manager.c
@@ -906,7 +906,101 @@ refresh_tray_icon_menu_if_active (GsdXrandrManager *manager, guint32 timestamp)
 static void
 auto_configure_outputs (GsdXrandrManager *manager, guint32 timestamp)
 {
-        /* FMQ: implement */
+        GsdXrandrManagerPrivate *priv = manager->priv;
+        GnomeRRConfig *config;
+        int i;
+        GList *just_turned_on;
+        GList *l;
+        int x;
+        GError *error;
+
+        config = gnome_rr_config_new_current (priv->rw_screen);
+
+        /* For outputs that are connected and on (i.e. they have a CRTC assigned
+         * to them, so they are getting a signal), we leave them as they are
+         * with their current modes.
+         *
+         * For other outputs, we will turn on connected-but-off outputs and turn
+         * off disconnected-but-on outputs.
+         *
+         * FIXME: If an output remained connected+on, it would be nice to ensure
+         * that the output's CRTCs still has a reasonable mode (think of
+         * changing one monitor for another with different capabilities).
+         */
+
+        just_turned_on = NULL;
+
+        for (i = 0; config->outputs[i] != NULL; i++) {
+                GnomeOutputInfo *output = config->outputs[i];
+
+                if (output->connected && !output->on) {
+                        output->on = TRUE;
+                        output->rotation = GNOME_RR_ROTATION_0;
+                        just_turned_on = g_list_prepend (just_turned_on, GINT_TO_POINTER (i));
+                } else if (!output->connected && output->on)
+                        output->on = FALSE;
+        }
+
+        /* Now, lay out the outputs from left to right.  Put first the outputs
+         * which remained on; put last the outputs that were newly turned on.
+         */
+
+        x = 0;
+
+        /* First, outputs that remained on */
+
+        for (i = 0; config->outputs[i] != NULL; i++) {
+                GnomeOutputInfo *output = config->outputs[i];
+
+                if (g_list_find (just_turned_on, GINT_TO_POINTER (i)))
+                        continue;
+
+                if (output->on) {
+                        g_assert (output->connected);
+
+                        output->x = x;
+                        output->y = 0;
+
+                        x += output->width;
+                }
+        }
+
+        /* Second, outputs that were newly-turned on */
+
+        for (l = just_turned_on; l; l = l->next) {
+                GnomeOutputInfo *output;
+
+                i = GPOINTER_TO_INT (l->data);
+                output = config->outputs[i];
+
+                g_assert (output->on && output->connected);
+
+                output->x = x;
+                output->y = 0;
+
+                /* since the output was off, use its preferred width/height (it doesn't have a real width/height yet) */
+                output->width = output->pref_width;
+                output->height = output->pref_height;
+
+                x += output->width;
+        }
+
+        /* Apply the configuration! */
+
+        error = NULL;
+        if (!gnome_rr_config_apply_with_time (config, priv->rw_screen, timestamp, &error)) {
+                error_message (manager, _("Could not switch the monitor configuration"), error, NULL);
+                g_error_free (error);
+        }
+
+        g_list_free (just_turned_on);
+        gnome_rr_config_free (config);
+
+        /* Finally, even though we did a best-effort job in sanitizing the
+         * outputs, we don't know the physical layout of the monitors.  We'll
+         * start the display capplet so that the user can tweak things to his
+         * liking.
+         */
 }
 
 static void