1 files changed, 22 insertions, 3 deletions
diff --git a/gst-libs/gst/gl/win32/gstglcontext_wgl.c b/gst-libs/gst/gl/win32/gstglcontext_wgl.c
index 826ab44..88e35af 100644
--- a/gst-libs/gst/gl/win32/gstglcontext_wgl.c
+++ b/gst-libs/gst/gl/win32/gstglcontext_wgl.c
@@ -40,7 +40,7 @@ static gboolean gst_gl_context_wgl_choose_format (GstGLContext * context,
 static gboolean gst_gl_context_wgl_activate (GstGLContext * context,
     gboolean activate);
 static gboolean gst_gl_context_wgl_create_context (GstGLContext * context,
-    GstGLAPI gl_api, guintptr external_gl_context, GError ** error);
+    GstGLAPI gl_api, GstGLContext * other_context, GError ** error);
 static void gst_gl_context_wgl_destroy_context (GstGLContext * context);
 GstGLAPI gst_gl_context_wgl_get_gl_api (GstGLContext * context);
 static gpointer gst_gl_context_wgl_get_proc_address (GstGLContext * context,
@@ -84,23 +84,33 @@ gst_gl_context_wgl_new (void)
 
 static gboolean
 gst_gl_context_wgl_create_context (GstGLContext * context,
-    GstGLAPI gl_api, guintptr external_gl_context, GError ** error)
+    GstGLAPI gl_api, GstGLContext * other_context, GError ** error)
 {
   GstGLWindow *window;
   GstGLContextWGL *context_wgl;
+  GstGLContextWGL *other_wgl = NULL;
   HDC device;
 
   context_wgl = GST_GL_CONTEXT_WGL (context);
   window = gst_gl_context_get_window (context);
   device = (HDC) gst_gl_window_get_display (window);
 
+  if (other_context) {
+    if (!GST_GL_IS_CONTEXT_WGL (other_context)) {
+      g_set_error (error, GST_GL_WINDOW_ERROR, GST_GL_WINDOW_ERROR_WRONG_CONFIG,
+          "Cannot share context with a non-WGL context");
+      goto failure;
+    }
+    other_wgl = (GstGLContextWGL *) other_context;
+  }
+
   context_wgl->wgl_context = wglCreateContext (device);
   if (context_wgl->wgl_context)
     GST_DEBUG ("gl context created: %" G_GUINTPTR_FORMAT,
         (guintptr) context_wgl->wgl_context);
   else {
     g_set_error (error, GST_GL_WINDOW_ERROR, GST_GL_WINDOW_ERROR_CREATE_CONTEXT,
-        "failed to create glcontext:%lu", GetLastError ());
+        "failed to create glcontext:0x%x", (unsigned int) GetLastError ());
     goto failure;
   }
   g_assert (context_wgl->wgl_context);
@@ -108,6 +118,15 @@ gst_gl_context_wgl_create_context (GstGLContext * context,
   GST_LOG ("gl context id: %" G_GUINTPTR_FORMAT,
       (guintptr) context_wgl->wgl_context);
 
+  if (other_wgl) {
+    if (!wglShareLists (other_wgl->wgl_context, context_wgl->wgl_context)) {
+      g_set_error (error, GST_GL_WINDOW_ERROR,
+          GST_GL_WINDOW_ERROR_CREATE_CONTEXT, "failed to share contexts 0x%x",
+          (unsigned int) GetLastError ());
+      goto failure;
+    }
+  }
+
   gst_object_unref (window);
 
   return TRUE;