--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gst_plugins_base/gst-libs/gst/interfaces/xoverlay.c	Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,292 @@
+/* GStreamer X-based Overlay
+ * Copyright (C) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>
+ *
+ * x-overlay.c: X-based overlay interface design
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:gstxoverlay
+ * @short_description: Interface for setting/getting a Window on elements
+ * supporting it
+ *
+ * <refsect2>
+ * <para>
+ * The XOverlay interface is used for 2 main purposes :
+ * <itemizedlist>
+ * <listitem>
+ * <para>
+ * To get a grab on the Window where the video sink element is going to render.
+ * This is achieved by either being informed about the Window identifier that
+ * the video sink element generated, or by forcing the video sink element to use
+ * a specific Window identifier for rendering.
+ * </para>
+ * </listitem>
+ * <listitem>
+ * <para>
+ * To force a redrawing of the latest video frame the video sink element
+ * displayed on the Window. Indeed if the #GstPipeline is in #GST_STATE_PAUSED
+ * state, moving the Window around will damage its content. Application
+ * developers will want to handle the Expose events themselves and force the
+ * video sink element to refresh the Window's content.
+ * </para>
+ * </listitem>
+ * </itemizedlist>
+ * </para>
+ * <para>
+ * Using the Window created by the video sink is probably the simplest scenario,
+ * in some cases, though, it might not be flexible enough for application
+ * developers if they need to catch events such as mouse moves and button
+ * clicks.
+ * </para>
+ * <para>
+ * Setting a specific Window identifier on the video sink element is the most
+ * flexible solution but it has some issues. Indeed the application needs to set
+ * its Window identifier at the right time to avoid internal Window creation
+ * from the video sink element. To solve this issue a #GstMessage is posted on
+ * the bus to inform the application that it should set the Window identifier
+ * immediately. Here is an example on how to do that correctly:
+ * <programlisting>
+ * static GstBusSyncReply
+ * create_window (GstBus * bus, GstMessage * message, GstPipeline * pipeline)
+ * {
+ *  // ignore anything but 'prepare-xwindow-id' element messages
+ *  if (GST_MESSAGE_TYPE (message) != GST_MESSAGE_ELEMENT)
+ *    return GST_BUS_PASS;
+ *  
+ *  if (!gst_structure_has_name (message-&gt;structure, "prepare-xwindow-id"))
+ *    return GST_BUS_PASS;
+ *  
+ *  win = XCreateSimpleWindow (disp, root, 0, 0, 320, 240, 0, 0, 0);
+ *  
+ *  XSetWindowBackgroundPixmap (disp, win, None);
+ *  
+ *  XMapRaised (disp, win);
+ *  
+ *  XSync (disp, FALSE);
+ *   
+ *  gst_x_overlay_set_xwindow_id (GST_X_OVERLAY (GST_MESSAGE_SRC (message)),
+ *      win);
+ *   
+ *  gst_message_unref (message);
+ *   
+ *  return GST_BUS_DROP;
+ * }
+ * ...
+ * int
+ * main (int argc, char **argv)
+ * {
+ * ...
+ *  bus = gst_pipeline_get_bus (GST_PIPELINE (pipeline));
+ *  gst_bus_set_sync_handler (bus, (GstBusSyncHandler) create_window, pipeline);
+ * ...
+ * }
+ * </programlisting>
+ * </para>
+ * </refsect2>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "xoverlay.h"
+
+static void gst_x_overlay_base_init (gpointer g_class);
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+GType
+gst_x_overlay_get_type (void)
+{
+  static GType gst_x_overlay_type = 0;
+
+  if (!gst_x_overlay_type) {
+    static const GTypeInfo gst_x_overlay_info = {
+      sizeof (GstXOverlayClass),
+      gst_x_overlay_base_init,
+      NULL,
+      NULL,
+      NULL,
+      NULL,
+      0,
+      0,
+      NULL,
+    };
+
+    gst_x_overlay_type = g_type_register_static (G_TYPE_INTERFACE,
+        "GstXOverlay", &gst_x_overlay_info, 0);
+    g_type_interface_add_prerequisite (gst_x_overlay_type,
+        GST_TYPE_IMPLEMENTS_INTERFACE);
+  }
+
+  return gst_x_overlay_type;
+}
+
+static void
+gst_x_overlay_base_init (gpointer g_class)
+{
+  GstXOverlayClass *overlay_class = (GstXOverlayClass *) g_class;
+
+  overlay_class->set_xwindow_id = NULL;
+}
+
+/**
+ * gst_x_overlay_set_xwindow_id:
+ * @overlay: a #GstXOverlay to set the XWindow on.
+ * @xwindow_id: a #XID referencing the XWindow.
+ *
+ * This will call the video overlay's set_xwindow_id method. You should
+ * use this method to tell to a XOverlay to display video output to a
+ * specific XWindow. Passing 0 as the xwindow_id will tell the overlay to
+ * stop using that window and create an internal one.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_x_overlay_set_xwindow_id (GstXOverlay * overlay, gulong xwindow_id)
+{
+  GstXOverlayClass *klass;
+
+  g_return_if_fail (overlay != NULL);
+  g_return_if_fail (GST_IS_X_OVERLAY (overlay));
+
+  klass = GST_X_OVERLAY_GET_CLASS (overlay);
+
+  if (klass->set_xwindow_id) {
+    klass->set_xwindow_id (overlay, xwindow_id);
+  }
+}
+
+/**
+ * gst_x_overlay_got_xwindow_id:
+ * @overlay: a #GstXOverlay which got a XWindow.
+ * @xwindow_id: a #XID referencing the XWindow.
+ *
+ * This will post a "have-xwindow-id" element message on the bus.
+ *
+ * This function should only be used by video overlay plugin developers.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_x_overlay_got_xwindow_id (GstXOverlay * overlay, gulong xwindow_id)
+{
+  GstStructure *s;
+  GstMessage *msg;
+
+  g_return_if_fail (overlay != NULL);
+  g_return_if_fail (GST_IS_X_OVERLAY (overlay));
+
+  GST_LOG_OBJECT (GST_OBJECT (overlay), "xwindow_id = %lu", xwindow_id);
+  s = gst_structure_new ("have-xwindow-id", "xwindow-id", G_TYPE_ULONG,
+      xwindow_id, NULL);
+  msg = gst_message_new_element (GST_OBJECT (overlay), s);
+  gst_element_post_message (GST_ELEMENT (overlay), msg);
+}
+
+/**
+ * gst_x_overlay_prepare_xwindow_id:
+ * @overlay: a #GstXOverlay which does not yet have an XWindow.
+ *
+ * This will post a "prepare-xwindow-id" element message on the bus
+ * to give applications an opportunity to call 
+ * gst_x_overlay_set_xwindow_id() before a plugin creates its own
+ * window.
+ *
+ * This function should only be used by video overlay plugin developers.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_x_overlay_prepare_xwindow_id (GstXOverlay * overlay)
+{
+  GstStructure *s;
+  GstMessage *msg;
+
+  g_return_if_fail (overlay != NULL);
+  g_return_if_fail (GST_IS_X_OVERLAY (overlay));
+
+  GST_LOG_OBJECT (GST_OBJECT (overlay), "prepare xwindow_id");
+  s = gst_structure_new ("prepare-xwindow-id", NULL);
+  msg = gst_message_new_element (GST_OBJECT (overlay), s);
+  gst_element_post_message (GST_ELEMENT (overlay), msg);
+}
+
+/**
+ * gst_x_overlay_expose:
+ * @overlay: a #GstXOverlay to expose.
+ *
+ * Tell an overlay that it has been exposed. This will redraw the current frame
+ * in the drawable even if the pipeline is PAUSED.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_x_overlay_expose (GstXOverlay * overlay)
+{
+  GstXOverlayClass *klass;
+
+  g_return_if_fail (overlay != NULL);
+  g_return_if_fail (GST_IS_X_OVERLAY (overlay));
+
+  klass = GST_X_OVERLAY_GET_CLASS (overlay);
+
+  if (klass->expose) {
+    klass->expose (overlay);
+  }
+}
+
+/**
+ * gst_x_overlay_handle_events:
+ * @overlay: a #GstXOverlay to expose.
+ * @handle_events: a #gboolean indicating if events should be handled or not.
+ *
+ * Tell an overlay that it should handle events from the window system. These
+ * events are forwared upstream as navigation events. In some window system,
+ * events are not propagated in the window hierarchy if a client is listening
+ * for them. This method allows you to disable events handling completely
+ * from the XOverlay.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+void
+gst_x_overlay_handle_events (GstXOverlay * overlay, gboolean handle_events)
+{
+  GstXOverlayClass *klass;
+
+  g_return_if_fail (overlay != NULL);
+  g_return_if_fail (GST_IS_X_OVERLAY (overlay));
+
+  klass = GST_X_OVERLAY_GET_CLASS (overlay);
+
+  if (klass->handle_events) {
+    klass->handle_events (overlay, handle_events);
+  }
+}