untested hack for AU multi-bus outputs which are not explicitly listed

diff --git a/libs/ardour/audio_unit.cc b/libs/ardour/audio_unit.cc
index 74e0cc280036fffde6c6f9e6007d53c8d6917b9b..c9c5565e3bbad09009520ba85a91d11f1b3f0cfa 100644 (file)
--- a/libs/ardour/audio_unit.cc
+++ b/libs/ardour/audio_unit.cc
@@ -1275,6 +1275,24 @@ AUPlugin::can_support_io_configuration (const ChanCount& in, ChanCount& out, Cha
                }
        }
 
+       if (output_elements > 1) {
+               const vector<pair<int,int> >& ioc (pinfo->cache.io_configs);
+               for (vector<pair<int,int> >::const_iterator i = ioc.begin(); i != ioc.end(); ++i) {
+                       int32_t possible_in = i->first;
+                       int32_t possible_out = i->second;
+                       if (possible_in < 1 || possible_out < 1) {
+                               continue;
+                       }
+                       for (uint32_t i = 1; i < output_elements; ++i) {
+                               int32_t c = bus_outputs[i];
+                               for (uint32_t j = 1; j < i; ++j) {
+                                       c += bus_outputs [j];
+                               }
+                               io_configs.push_back (pair<int,int> (possible_in, possible_out + c));
+                       }
+               }
+       }
+
        DEBUG_TRACE (DEBUG::AudioUnits, string_compose ("%1 has %2 IO configurations, looking for %3 in, %4 out\n",
                                                        name(), io_configs.size(), in, out));