[rygel/docs] renderer: Improve the Playbin.Renderer documentation.

[Murray Cumming <murrayc src gnome org>]

commit c04b2ae415ba5f72a9897565db1380973340e75a
Author: Murray Cumming <murrayc murrayc com>
Date:   Mon Sep 10 13:40:21 2012 +0200

    renderer: Improve the Playbin.Renderer documentation.
    
    Based on examples/standalone-renderer.c

 src/librygel-renderer/rygel-playbin-renderer.vala |   11 +++++++++++
 1 files changed, 11 insertions(+), 0 deletions(-)
---
diff --git a/src/librygel-renderer/rygel-playbin-renderer.vala b/src/librygel-renderer/rygel-playbin-renderer.vala
index 901c2c8..e30c73a 100644
--- a/src/librygel-renderer/rygel-playbin-renderer.vala
+++ b/src/librygel-renderer/rygel-playbin-renderer.vala
@@ -42,6 +42,17 @@ internal class Rygel.Playbin.WrappingPlugin : Rygel.MediaRendererPlugin {
  * changing the currently played URI, volume, pause/play etc., to UPnP.
  *
  * Likewise, the playbin can be modified externally using UPnP.
+ *
+ * You can retrieve the Gst.Playbin2 by calling rygel_playbin_player_get_playbin()
+ * on the default player - see rygel_playbin_player_get_default().
+ * You should then set the "video-sink" and "audio-sink" properties of the
+ * playbin.
+ *
+ * Call rygel_media_device_add_interface() on the Renderer to allow it
+ * to be controlled by a control point and to retrieve data streams via that
+ * network interface.
+ *
+ * See the standalone-renderer.c example.
  */
 public class Rygel.Playbin.Renderer : Rygel.MediaDevice {
     /**