[gnome-flashback] display-config: set the underscan border properties, too

[Alberts Muktupāvels <muktupavels src gnome org>]

commit 8ff3f5233cb6f6a5b3b5b452676fc3c36c13196f
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Mon Apr 27 17:23:56 2015 -0700

    display-config: set the underscan border properties, too

 .../libdisplay-config/flashback-monitor-manager.c  |   25 +++++++++++++++++++-
 1 files changed, 24 insertions(+), 1 deletions(-)
---
diff --git a/gnome-flashback/libdisplay-config/flashback-monitor-manager.c 
b/gnome-flashback/libdisplay-config/flashback-monitor-manager.c
index 22c41cd..c770707 100644
--- a/gnome-flashback/libdisplay-config/flashback-monitor-manager.c
+++ b/gnome-flashback/libdisplay-config/flashback-monitor-manager.c
@@ -1235,7 +1235,6 @@ output_set_underscanning_xrandr (FlashbackMonitorManagerPrivate *priv,
 
   prop = XInternAtom (priv->xdisplay, "underscan", False);
 
-  /* XXX: Also implement underscan border */
   value = underscanning ? "on" : "off";
   valueatom = XInternAtom (priv->xdisplay, value, False);
 
@@ -1244,6 +1243,30 @@ output_set_underscanning_xrandr (FlashbackMonitorManagerPrivate *priv,
                            prop,
                            XA_ATOM, 32, PropModeReplace,
                            (unsigned char*) &valueatom, 1);
+
+  /* Configure the border at the same time. Currently, we use a
+   * 5% of the width/height of the mode. In the future, we should
+   * make the border configurable. */
+  if (underscanning)
+    {
+      uint32_t border_value;
+
+      prop = XInternAtom (priv->xdisplay, "underscan hborder", False);
+      border_value = output->crtc->current_mode->width * 0.05;
+      XRRChangeOutputProperty (priv->xdisplay,
+                               (XID)output->winsys_id,
+                               prop,
+                               XA_INTEGER, 32, PropModeReplace,
+                               (unsigned char *) &border_value, 1);
+
+      prop = XInternAtom (priv->xdisplay, "underscan vborder", False);
+      border_value = output->crtc->current_mode->height * 0.05;
+      XRRChangeOutputProperty (priv->xdisplay,
+                               (XID)output->winsys_id,
+                               prop,
+                               XA_INTEGER, 32, PropModeReplace,
+                               (unsigned char *) &border_value, 1);
+    }
 }
 
 void