Added embedding functions

go.mod

@@ -1,3 +1,4 @@
 module github.com/notedit/gst
 
 go 1.12
+

go.sum

@@ -0,0 +1,2 @@
+github.com/BurntSushi/xgb v0.0.0-20200324125942-20f126ea2843 h1:3iF31c7rp7nGZVDv7YQ+VxOgpipVfPKotLXykjZmwM8=
+github.com/BurntSushi/xgb v0.0.0-20200324125942-20f126ea2843/go.mod h1:IVnqGOEym/WlBOVXweHU+Q+/VP0lqqI8lqeDx9IjBqo=

gst.h

@@ -7,6 +7,7 @@
 
 
 
+
 typedef struct ElementUserData {
     guint64 callbackId;
 } ElementUserData;

overlay.go

@@ -0,0 +1,37 @@
+package gst
+
+/*
+#cgo pkg-config: gstreamer-1.0 gstreamer-video-1.0
+#include "gst.h"
+#include <glib.h>
+#include <gst/video/videooverlay.h>
+*/
+import (
+	"C"
+)
+import "unsafe"
+
+// VideoOverlaySetWindowHandle will call the video overlay's set_window_handle method.
+// You should use this method to tell to an overlay to display video output to a specific window
+// (e.g. an XWindow on X11). Passing 0 as the handle will tell the overlay to stop using that
+// window and create an internal one. registers the windowID for video output of the element.
+func (e *Element) VideoOverlaySetWindowHandle(windowID uintptr) {
+	C.gst_video_overlay_set_window_handle((*C.GstVideoOverlay)(unsafe.Pointer(e.GstElement)), (C.guintptr)(windowID))
+}
+
+// VideoOverlayExpose tells an overlay that it has been exposed. This will redraw the current frame in the drawable even if the pipeline is PAUSED.
+func (e *Element) VideoOverlayExpose() {
+	C.gst_video_overlay_expose((*C.GstVideoOverlay)(unsafe.Pointer(e.GstElement)))
+}
+
+// VideoOverlayHandleEvents tells an overlay that it should handle events from the window system.
+// These events are forwarded 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 GstVideoOverlay.
+func (e *Element) VideoOverlayHandleEvents(handleEvents bool) {
+	bInt := int(0)
+	if handleEvents {
+		bInt = 1
+	}
+	C.gst_video_overlay_handle_events((*C.GstVideoOverlay)(unsafe.Pointer(e.GstElement)), (C.gboolean)(bInt))
+}