glmixer: override the caps query in order to 'convert' capsfeatures

Otherwise, it is only possible for the sink pads and the src pads to
have the exact same caps features.  We can convert from any feature
to another feature so support that.

diff --git a/ext/gl/gstglmixer.c b/ext/gl/gstglmixer.c
index da6ba67..a80d2b7 100644 (file)
--- a/ext/gl/gstglmixer.c
+++ b/ext/gl/gstglmixer.c
@@ -287,6 +287,37 @@ gst_gl_mixer_pad_sink_acceptcaps (GstPad * pad, GstGLMixer * mix,
   return ret;
 }
 
+static GstCaps *
+gst_gl_mixer_pad_sink_getcaps (GstPad * pad, GstGLMixer * mix, GstCaps * filter)
+{
+  GstCaps *srccaps;
+  GstCaps *template_caps;
+  GstCaps *filtered_caps;
+  GstCaps *returned_caps;
+  gboolean had_current_caps = TRUE;
+
+  template_caps = gst_pad_get_pad_template_caps (pad);
+
+  srccaps = gst_pad_get_current_caps (pad);
+  if (srccaps == NULL) {
+    had_current_caps = FALSE;
+    srccaps = template_caps;
+  }
+
+  filtered_caps = srccaps;
+  if (filter)
+    filtered_caps = gst_caps_intersect (srccaps, filter);
+  returned_caps = gst_caps_intersect (filtered_caps, template_caps);
+
+  gst_caps_unref (srccaps);
+  if (filter)
+    gst_caps_unref (filtered_caps);
+  if (had_current_caps)
+    gst_caps_unref (template_caps);
+
+  return returned_caps;
+}
+
 static gboolean
 gst_gl_mixer_sink_query (GstAggregator * agg, GstAggregatorPad * bpad,
     GstQuery * query)
@@ -297,6 +328,17 @@ gst_gl_mixer_sink_query (GstAggregator * agg, GstAggregatorPad * bpad,
   GST_TRACE ("QUERY %" GST_PTR_FORMAT, query);
 
   switch (GST_QUERY_TYPE (query)) {
+    case GST_QUERY_CAPS:
+    {
+      GstCaps *filter, *caps;
+
+      gst_query_parse_caps (query, &filter);
+      caps = gst_gl_mixer_pad_sink_getcaps (GST_PAD (bpad), mix, filter);
+      gst_query_set_caps_result (query, caps);
+      gst_caps_unref (caps);
+      ret = TRUE;
+      break;
+    }
     case GST_QUERY_ACCEPT_CAPS:
     {
       GstCaps *caps;