playbin2: allow dynamic swtiching of subtitles

When we have the textpad configured, enable and disable the subtitles by setting
the silent flag on the overlay element instead of trying to remove elements.
See #576187

diff --git a/gst/playback/gstplaysink.c b/gst/playback/gstplaysink.c
index cbd42c5..6f4365e 100644 (file)
--- a/gst/playback/gstplaysink.c
+++ b/gst/playback/gstplaysink.c
@@ -1434,7 +1434,7 @@ gst_play_sink_reconfigure (GstPlaySink * playsink)
       add_chain (GST_PLAY_CHAIN (playsink->videochain), TRUE);
       activate_chain (GST_PLAY_CHAIN (playsink->videochain), TRUE);
       /* if we are not part of vis or subtitles, set the ghostpad target */
-      if (!need_vis && !need_text) {
+      if (!need_vis && !need_text && playsink->text_pad == NULL) {
         GST_DEBUG_OBJECT (playsink, "ghosting video sinkpad");
         gst_ghost_pad_set_target (GST_GHOST_PAD_CAST (playsink->video_pad),
             playsink->videochain->sinkpad);
@@ -1458,8 +1458,8 @@ gst_play_sink_reconfigure (GstPlaySink * playsink)
           playsink->audio_tee_vissrc = NULL;
         }
         srcpad =
-            gst_element_get_static_pad (GST_ELEMENT_CAST (playsink->
-                vischain->chain.bin), "src");
+            gst_element_get_static_pad (GST_ELEMENT_CAST (playsink->vischain->
+                chain.bin), "src");
         gst_pad_unlink (srcpad, playsink->videochain->sinkpad);
       }
       add_chain (GST_PLAY_CHAIN (playsink->videochain), FALSE);
@@ -1484,14 +1484,24 @@ gst_play_sink_reconfigure (GstPlaySink * playsink)
           playsink->textchain->videosinkpad);
       gst_pad_link (playsink->textchain->srcpad, playsink->videochain->sinkpad);
       activate_chain (GST_PLAY_CHAIN (playsink->textchain), TRUE);
+      if (playsink->textchain->overlay)
+        g_object_set (playsink->textchain->overlay, "silent", FALSE, NULL);
     }
   } else {
     GST_DEBUG_OBJECT (playsink, "no text needed");
     /* we have no subtitles/text or we are requested to not show them */
     if (playsink->textchain) {
-      GST_DEBUG_OBJECT (playsink, "removing text chain");
-      add_chain (GST_PLAY_CHAIN (playsink->textchain), FALSE);
-      activate_chain (GST_PLAY_CHAIN (playsink->textchain), FALSE);
+      if (playsink->text_pad == NULL) {
+        /* no text pad, remove the chain entirely */
+        GST_DEBUG_OBJECT (playsink, "removing text chain");
+        add_chain (GST_PLAY_CHAIN (playsink->textchain), FALSE);
+        activate_chain (GST_PLAY_CHAIN (playsink->textchain), FALSE);
+      } else {
+        /* we have a chain and a textpad, turn the subtitles off */
+        GST_DEBUG_OBJECT (playsink, "turning off the text");
+        if (playsink->textchain->overlay)
+          g_object_set (playsink->textchain->overlay, "silent", TRUE, NULL);
+      }
     }
     if (!need_video && playsink->video_pad)
       gst_ghost_pad_set_target (GST_GHOST_PAD_CAST (playsink->video_pad), NULL);
@@ -1581,8 +1591,8 @@ gst_play_sink_reconfigure (GstPlaySink * playsink)
     if (playsink->vischain) {
       GST_DEBUG_OBJECT (playsink, "setting up vis chain");
       srcpad =
-          gst_element_get_static_pad (GST_ELEMENT_CAST (playsink->
-              vischain->chain.bin), "src");
+          gst_element_get_static_pad (GST_ELEMENT_CAST (playsink->vischain->
+              chain.bin), "src");
       add_chain (GST_PLAY_CHAIN (playsink->vischain), TRUE);
       activate_chain (GST_PLAY_CHAIN (playsink->vischain), TRUE);
       if (playsink->audio_tee_vissrc == NULL) {