finally get to the bottom of where NO_PLUGIN_STATE needs to be in order to be useful
[ardour.git] / libs / ardour / lv2_plugin.cc
index cc03f9b193c9641d8c159d4018b48ca2b55d881f..5ea76934a5ffe85923ee5be67d6c052aaacb45c5 100644 (file)
@@ -1,5 +1,5 @@
 /*
-    Copyright (C) 2008-2011 Paul Davis
+    Copyright (C) 2008-2012 Paul Davis
     Author: David Robillard
 
     This program is free software; you can redistribute it and/or modify
     You should have received a copy of the GNU General Public License
     along with this program; if not, write to the Free Software
     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
-
 */
 
 #include <string>
 #include <vector>
+#include <limits>
 
 #include <cmath>
 #include <cstdlib>
 #include <cstring>
 
-#include <glibmm.h>
 #include <giomm/file.h>
+#include <glib/gprintf.h>
+#include <glibmm.h>
 
 #include <boost/utility.hpp>
 
+#include "pbd/pathscanner.h"
 #include "pbd/compose.h"
 #include "pbd/error.h"
-#include "pbd/pathscanner.h"
-#include "pbd/stl_delete.h"
 #include "pbd/xml++.h"
 
 #include "libardour-config.h"
 
-#include "ardour/ardour.h"
 #include "ardour/audio_buffer.h"
 #include "ardour/audioengine.h"
 #include "ardour/debug.h"
-#include "ardour/lv2_event_buffer.h"
 #include "ardour/lv2_plugin.h"
-#include "ardour/lv2_state.h"
 #include "ardour/session.h"
+#include "ardour/tempo.h"
+#include "ardour/types.h"
+#include "ardour/utils.h"
+#include "ardour/worker.h"
+#include "ardour/lv2_bundled_search_path.h"
 
 #include "i18n.h"
 #include <locale.h>
 
 #include <lilv/lilv.h>
 
+#include "lv2/lv2plug.in/ns/ext/atom/atom.h"
+#include "lv2/lv2plug.in/ns/ext/atom/forge.h"
+#include "lv2/lv2plug.in/ns/ext/log/log.h"
+#include "lv2/lv2plug.in/ns/ext/midi/midi.h"
+#include "lv2/lv2plug.in/ns/ext/port-props/port-props.h"
+#include "lv2/lv2plug.in/ns/ext/presets/presets.h"
 #include "lv2/lv2plug.in/ns/ext/state/state.h"
-#include "rdff.h"
+#include "lv2/lv2plug.in/ns/ext/time/time.h"
+#include "lv2/lv2plug.in/ns/ext/worker/worker.h"
+#include "lv2/lv2plug.in/ns/ext/resize-port/resize-port.h"
+#include "lv2/lv2plug.in/ns/extensions/ui/ui.h"
+#ifdef HAVE_NEW_LV2
+#include "lv2/lv2plug.in/ns/ext/buf-size/buf-size.h"
+#include "lv2/lv2plug.in/ns/ext/options/options.h"
+#endif
+
+#include "lv2_evbuf.h"
+
 #ifdef HAVE_SUIL
 #include <suil/suil.h>
 #endif
 
-#define NS_DC    "http://dublincore.org/documents/dcmi-namespace/"
-#define NS_LV2   "http://lv2plug.in/ns/lv2core#"
-#define NS_PSET  "http://lv2plug.in/ns/dev/presets#"
-#define NS_UI    "http://lv2plug.in/ns/extensions/ui#"
+/** The number of MIDI buffers that will fit in a UI/worker comm buffer.
+    This needs to be roughly the number of cycles the UI will get around to
+    actually processing the traffic.  Lower values are flakier but save memory.
+*/
+static const size_t NBUFS = 4;
 
 using namespace std;
 using namespace ARDOUR;
 using namespace PBD;
 
 URIMap LV2Plugin::_uri_map;
-uint32_t LV2Plugin::_midi_event_type = _uri_map.uri_to_id(
-        "http://lv2plug.in/ns/ext/event",
-        "http://lv2plug.in/ns/ext/midi#MidiEvent");
-uint32_t LV2Plugin::_state_path_type = _uri_map.uri_to_id(
-        NULL, LV2_STATE_PATH_URI);
+
+LV2Plugin::URIDs LV2Plugin::urids = {
+       _uri_map.uri_to_id(LV2_ATOM__Chunk),
+       _uri_map.uri_to_id(LV2_ATOM__Path),
+       _uri_map.uri_to_id(LV2_ATOM__Sequence),
+       _uri_map.uri_to_id(LV2_ATOM__eventTransfer),
+       _uri_map.uri_to_id(LV2_LOG__Error),
+       _uri_map.uri_to_id(LV2_LOG__Note),
+       _uri_map.uri_to_id(LV2_LOG__Warning),
+       _uri_map.uri_to_id(LV2_MIDI__MidiEvent),
+       _uri_map.uri_to_id(LV2_TIME__Position),
+       _uri_map.uri_to_id(LV2_TIME__bar),
+       _uri_map.uri_to_id(LV2_TIME__barBeat),
+       _uri_map.uri_to_id(LV2_TIME__beatUnit),
+       _uri_map.uri_to_id(LV2_TIME__beatsPerBar),
+       _uri_map.uri_to_id(LV2_TIME__beatsPerMinute),
+       _uri_map.uri_to_id(LV2_TIME__frame),
+       _uri_map.uri_to_id(LV2_TIME__speed)
+};
 
 class LV2World : boost::noncopyable {
 public:
        LV2World ();
        ~LV2World ();
 
+       void load_bundled_plugins();
+
        LilvWorld* world;
-       LilvNode*  input_class;      ///< Input port
-       LilvNode*  output_class;     ///< Output port
-       LilvNode*  audio_class;      ///< Audio port
-       LilvNode*  control_class;    ///< Control port
-       LilvNode*  event_class;      ///< Event port
-       LilvNode*  midi_class;       ///< MIDI event
-       LilvNode*  in_place_broken;
-       LilvNode*  integer;
-       LilvNode*  toggled;
-       LilvNode*  srate;
-       LilvNode*  gtk_gui;
-       LilvNode*  external_gui;
-       LilvNode*  logarithmic;
+
+       LilvNode* atom_AtomPort;
+       LilvNode* atom_Chunk;
+       LilvNode* atom_Sequence;
+       LilvNode* atom_bufferType;
+       LilvNode* atom_eventTransfer;
+       LilvNode* atom_supports;
+       LilvNode* ev_EventPort;
+       LilvNode* ext_logarithmic;
+       LilvNode* ext_notOnGUI;
+       LilvNode* lv2_AudioPort;
+       LilvNode* lv2_ControlPort;
+       LilvNode* lv2_InputPort;
+       LilvNode* lv2_OutputPort;
+       LilvNode* lv2_enumeration;
+       LilvNode* lv2_freewheeling;
+       LilvNode* lv2_inPlaceBroken;
+       LilvNode* lv2_integer;
+       LilvNode* lv2_reportsLatency;
+       LilvNode* lv2_sampleRate;
+       LilvNode* lv2_toggled;
+       LilvNode* midi_MidiEvent;
+       LilvNode* rdfs_comment;
+       LilvNode* rsz_minimumSize;
+       LilvNode* time_Position;
+       LilvNode* ui_GtkUI;
+       LilvNode* ui_external;
+
+private:
+       bool _bundle_checked;
 };
 
 static LV2World _world;
 
+/* worker extension */
+
+/** Called by the plugin to schedule non-RT work. */
+static LV2_Worker_Status
+work_schedule(LV2_Worker_Schedule_Handle handle,
+              uint32_t                   size,
+              const void*                data)
+{
+       LV2Plugin* plugin = (LV2Plugin*)handle;
+       if (plugin->session().engine().freewheeling()) {
+               // Freewheeling, do the work immediately in this (audio) thread
+               return (LV2_Worker_Status)plugin->work(size, data);
+       } else {
+               // Enqueue message for the worker thread
+               return plugin->worker()->schedule(size, data) ?
+                       LV2_WORKER_SUCCESS : LV2_WORKER_ERR_UNKNOWN;
+       }
+}
+
+/** Called by the plugin to respond to non-RT work. */
+static LV2_Worker_Status
+work_respond(LV2_Worker_Respond_Handle handle,
+             uint32_t                  size,
+             const void*               data)
+{
+       LV2Plugin* plugin = (LV2Plugin*)handle;
+       if (plugin->session().engine().freewheeling()) {
+               // Freewheeling, respond immediately in this (audio) thread
+               return (LV2_Worker_Status)plugin->work_response(size, data);
+       } else {
+               // Enqueue response for the worker
+               return plugin->worker()->respond(size, data) ?
+                       LV2_WORKER_SUCCESS : LV2_WORKER_ERR_UNKNOWN;
+       }
+}
+
+/* log extension */
+
+static int
+log_vprintf(LV2_Log_Handle /*handle*/,
+            LV2_URID       type,
+            const char*    fmt,
+            va_list        args)
+{
+       char* str = NULL;
+       const int ret = g_vasprintf(&str, fmt, args);
+       if (type == LV2Plugin::urids.log_Error) {
+               error << str << endmsg;
+       } else if (type == LV2Plugin::urids.log_Warning) {
+               warning << str << endmsg;
+       } else if (type == LV2Plugin::urids.log_Note) {
+               info << str << endmsg;
+       }
+       // TODO: Toggleable log:Trace message support
+       return ret;
+}
+
+static int
+log_printf(LV2_Log_Handle handle,
+           LV2_URID       type,
+           const char*    fmt, ...)
+{
+       va_list args;
+       va_start(args, fmt);
+       const int ret = log_vprintf(handle, type, fmt, args);
+       va_end(args);
+       return ret;
+}
+
 struct LV2Plugin::Impl {
-       Impl() : plugin(0), ui(0), ui_type(0), name(0), author(0), instance(0) {}
-       LilvPlugin*     plugin;
-       const LilvUI*   ui;
-       const LilvNode* ui_type;
-       LilvNode*       name;
-       LilvNode*       author;
-       LilvInstance*   instance;
+       Impl() : plugin(0), ui(0), ui_type(0), name(0), author(0), instance(0)
+              , work_iface(0)
+              , state(0)
+       {}
+
+       /** Find the LV2 input port with the given designation.
+        * If found, bufptrs[port_index] will be set to bufptr.
+        */
+       const LilvPort* designated_input (const char* uri, void** bufptrs[], void** bufptr);
+
+       const LilvPlugin*           plugin;
+       const LilvUI*               ui;
+       const LilvNode*             ui_type;
+       LilvNode*                   name;
+       LilvNode*                   author;
+       LilvInstance*               instance;
+       const LV2_Worker_Interface* work_iface;
+       LilvState*                  state;
+       LV2_Atom_Forge              forge;
 };
 
 LV2Plugin::LV2Plugin (AudioEngine& engine,
                       Session&     session,
-                      void*        c_plugin,
+                      const void*  c_plugin,
                       framecnt_t   rate)
-       : Plugin(engine, session)
+       : Plugin (engine, session)
+       , Workee ()
        , _impl(new Impl())
        , _features(NULL)
+       , _worker(NULL)
        , _insert_id("0")
 {
        init(c_plugin, rate);
 }
 
 LV2Plugin::LV2Plugin (const LV2Plugin& other)
-       : Plugin(other)
+       : Plugin (other)
+       , Workee ()
        , _impl(new Impl())
        , _features(NULL)
+       , _worker(NULL)
        , _insert_id(other._insert_id)
 {
        init(other._impl->plugin, other._sample_rate);
@@ -134,56 +271,83 @@ LV2Plugin::LV2Plugin (const LV2Plugin& other)
 }
 
 void
-LV2Plugin::init(void* c_plugin, framecnt_t rate)
+LV2Plugin::init(const void* c_plugin, framecnt_t rate)
 {
        DEBUG_TRACE(DEBUG::LV2, "init\n");
 
-       _impl->plugin         = (LilvPlugin*)c_plugin;
-       _impl->ui             = NULL;
-       _impl->ui_type        = NULL;
-       _control_data         = 0;
-       _shadow_data          = 0;
-       _latency_control_port = 0;
-       _was_activated        = false;
+       _impl->plugin           = (const LilvPlugin*)c_plugin;
+       _impl->ui               = NULL;
+       _impl->ui_type          = NULL;
+       _to_ui                  = NULL;
+       _from_ui                = NULL;
+       _control_data           = 0;
+       _shadow_data            = 0;
+       _atom_ev_buffers        = 0;
+       _ev_buffers             = 0;
+       _bpm_control_port       = 0;
+       _freewheel_control_port = 0;
+       _latency_control_port   = 0;
+       _next_cycle_start       = std::numeric_limits<framepos_t>::max();
+       _next_cycle_speed       = 1.0;
+       _block_length           = _engine.frames_per_cycle();
+       _seq_size               = _engine.raw_buffer_size(DataType::MIDI);
+       _state_version          = 0;
+       _was_activated          = false;
+       _has_state_interface    = false;
 
        _instance_access_feature.URI = "http://lv2plug.in/ns/ext/instance-access";
        _data_access_feature.URI     = "http://lv2plug.in/ns/ext/data-access";
-       _map_path_feature.URI        = LV2_STATE_MAP_PATH_URI;
-       _make_path_feature.URI       = LV2_STATE_MAKE_PATH_URI;
-
-       LilvPlugin* plugin = _impl->plugin;
-
-       LilvNode* state_iface_uri = lilv_new_uri(_world.world, LV2_STATE_INTERFACE_URI);
-#ifdef lilv_plugin_has_extension_data
-       _has_state_interface = lilv_plugin_has_extension_data(plugin, state_iface_uri);
+       _make_path_feature.URI       = LV2_STATE__makePath;
+       _log_feature.URI             = LV2_LOG__log;
+       _work_schedule_feature.URI   = LV2_WORKER__schedule;
+       _work_schedule_feature.data  = NULL;
+       _def_state_feature.URI       = LV2_STATE_PREFIX "loadDefaultState";  // Post LV2-1.2.0
+       _def_state_feature.data      = NULL;
+
+       const LilvPlugin* plugin = _impl->plugin;
+
+       LilvNode* state_iface_uri = lilv_new_uri(_world.world, LV2_STATE__interface);
+       LilvNode* state_uri       = lilv_new_uri(_world.world, LV2_STATE_URI);
+       _has_state_interface =
+               // What plugins should have (lv2:extensionData state:Interface)
+               lilv_plugin_has_extension_data(plugin, state_iface_uri)
+               // What some outdated/incorrect ones have
+               || lilv_plugin_has_feature(plugin, state_uri);
+       lilv_node_free(state_uri);
        lilv_node_free(state_iface_uri);
-#else
-       LilvNode* lv2_extensionData = lilv_new_uri(_world.world, NS_LV2 "extensionData");
-       LilvNodes* extdatas = lilv_plugin_get_value(plugin, lv2_extensionData);
-       LILV_FOREACH(nodes, i, extdatas) {
-               if (lilv_node_equals(lilv_nodes_get(extdatas, i), state_iface_uri)) {
-                       _has_state_interface = true;
-                       break;
-               }
-       }
-#endif
 
-       _features    = (LV2_Feature**)malloc(sizeof(LV2_Feature*) * 8);
+       _features    = (LV2_Feature**)calloc(11, sizeof(LV2_Feature*));
        _features[0] = &_instance_access_feature;
        _features[1] = &_data_access_feature;
-       _features[2] = &_map_path_feature;
-       _features[3] = &_make_path_feature;
-       _features[4] = _uri_map.uri_map_feature();
-       _features[5] = _uri_map.urid_map_feature();
-       _features[6] = _uri_map.urid_unmap_feature();
-       _features[7] = NULL;
-
-       LV2_State_Map_Path* map_path = (LV2_State_Map_Path*)malloc(
-               sizeof(LV2_State_Map_Path));
-       map_path->handle = this;
-       map_path->abstract_path = &lv2_state_abstract_path;
-       map_path->absolute_path = &lv2_state_absolute_path;
-       _map_path_feature.data = map_path;
+       _features[2] = &_make_path_feature;
+       _features[3] = _uri_map.uri_map_feature();
+       _features[4] = _uri_map.urid_map_feature();
+       _features[5] = _uri_map.urid_unmap_feature();
+       _features[6] = &_log_feature;
+
+       unsigned n_features = 7;
+#ifdef HAVE_NEW_LV2
+       _features[n_features++] = &_def_state_feature;
+#endif
+
+       lv2_atom_forge_init(&_impl->forge, _uri_map.urid_map());
+
+#ifdef HAVE_NEW_LV2
+       LV2_URID atom_Int = _uri_map.uri_to_id(LV2_ATOM__Int);
+       LV2_Options_Option options[] = {
+               { LV2_OPTIONS_INSTANCE, 0, _uri_map.uri_to_id(LV2_BUF_SIZE__minBlockLength),
+                 sizeof(int32_t), atom_Int, &_block_length },
+               { LV2_OPTIONS_INSTANCE, 0, _uri_map.uri_to_id(LV2_BUF_SIZE__maxBlockLength),
+                 sizeof(int32_t), atom_Int, &_block_length },
+               { LV2_OPTIONS_INSTANCE, 0, _uri_map.uri_to_id(LV2_BUF_SIZE__sequenceSize),
+                 sizeof(int32_t), atom_Int, &_seq_size },
+               { LV2_OPTIONS_INSTANCE, 0, 0, 0, 0, NULL }
+       };
+
+       _options_feature.URI    = LV2_OPTIONS__options;
+       _options_feature.data   = options;
+       _features[n_features++] = &_options_feature;
+#endif
 
        LV2_State_Make_Path* make_path = (LV2_State_Make_Path*)malloc(
                sizeof(LV2_State_Make_Path));
@@ -191,6 +355,25 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
        make_path->path = &lv2_state_make_path;
        _make_path_feature.data = make_path;
 
+       LV2_Log_Log* log = (LV2_Log_Log*)malloc(sizeof(LV2_Log_Log));
+       log->handle  = this;
+       log->printf  = &log_printf;
+       log->vprintf = &log_vprintf;
+       _log_feature.data = log;
+
+       LilvNode* worker_schedule = lilv_new_uri(_world.world, LV2_WORKER__schedule);
+       if (lilv_plugin_has_feature(plugin, worker_schedule)) {
+               LV2_Worker_Schedule* schedule = (LV2_Worker_Schedule*)malloc(
+                       sizeof(LV2_Worker_Schedule));
+               size_t buf_size = _session.engine().raw_buffer_size(DataType::MIDI) * NBUFS;
+               _worker                     = new Worker(this, buf_size);
+               schedule->handle            = this;
+               schedule->schedule_work     = work_schedule;
+               _work_schedule_feature.data = schedule;
+               _features[n_features++]     = &_work_schedule_feature;
+       }
+       lilv_node_free(worker_schedule);
+
        _impl->instance = lilv_plugin_instantiate(plugin, rate, _features);
        _impl->name     = lilv_plugin_get_name(plugin);
        _impl->author   = lilv_plugin_get_author_name(plugin);
@@ -204,7 +387,14 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
        _data_access_extension_data.extension_data = _impl->instance->lv2_descriptor->extension_data;
        _data_access_feature.data                  = &_data_access_extension_data;
 
-       if (lilv_plugin_has_feature(plugin, _world.in_place_broken)) {
+       LilvNode* worker_iface_uri = lilv_new_uri(_world.world, LV2_WORKER__interface);
+       if (lilv_plugin_has_extension_data(plugin, worker_iface_uri)) {
+               _impl->work_iface = (const LV2_Worker_Interface*)extension_data(
+                       LV2_WORKER__interface);
+       }
+       lilv_node_free(worker_iface_uri);
+
+       if (lilv_plugin_has_feature(plugin, _world.lv2_inPlaceBroken)) {
                error << string_compose(
                    _("LV2: \"%1\" cannot be used, since it cannot do inplace processing"),
                    lilv_node_as_string(_impl->name)) << endmsg;
@@ -213,17 +403,93 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
                throw failed_constructor();
        }
 
+#ifdef HAVE_NEW_LILV
+       // Load default state
+       LilvState* state = lilv_state_new_from_world(
+               _world.world, _uri_map.urid_map(), lilv_plugin_get_uri(_impl->plugin));
+       if (state && _has_state_interface) {
+               lilv_state_restore(state, _impl->instance, NULL, NULL, 0, NULL);
+       }
+#endif
+
        _sample_rate = rate;
 
-       const uint32_t num_ports    = this->num_ports();
-       const bool     latent       = lilv_plugin_has_latency(plugin);
-       const uint32_t latency_port = (latent)
-           ? lilv_plugin_get_latency_port_index(plugin)
-               : 0;
+       const uint32_t num_ports = this->num_ports();
+       for (uint32_t i = 0; i < num_ports; ++i) {
+               const LilvPort* port  = lilv_plugin_get_port_by_index(_impl->plugin, i);
+               PortFlags       flags = 0;
+               size_t          minimumSize = 0;
+
+               if (lilv_port_is_a(_impl->plugin, port, _world.lv2_OutputPort)) {
+                       flags |= PORT_OUTPUT;
+               } else if (lilv_port_is_a(_impl->plugin, port, _world.lv2_InputPort)) {
+                       flags |= PORT_INPUT;
+               } else {
+                       error << string_compose(
+                               "LV2: \"%1\" port %2 is neither input nor output",
+                               lilv_node_as_string(_impl->name), i) << endmsg;
+                       throw failed_constructor();
+               }
+
+               if (lilv_port_is_a(_impl->plugin, port, _world.lv2_ControlPort)) {
+                       flags |= PORT_CONTROL;
+               } else if (lilv_port_is_a(_impl->plugin, port, _world.lv2_AudioPort)) {
+                       flags |= PORT_AUDIO;
+               } else if (lilv_port_is_a(_impl->plugin, port, _world.ev_EventPort)) {
+                       flags |= PORT_EVENT;
+                       flags |= PORT_MIDI;  // We assume old event API ports are for MIDI
+               } else if (lilv_port_is_a(_impl->plugin, port, _world.atom_AtomPort)) {
+                       LilvNodes* buffer_types = lilv_port_get_value(
+                               _impl->plugin, port, _world.atom_bufferType);
+                       LilvNodes* atom_supports = lilv_port_get_value(
+                               _impl->plugin, port, _world.atom_supports);
+
+                       if (lilv_nodes_contains(buffer_types, _world.atom_Sequence)) {
+                               flags |= PORT_SEQUENCE;
+                               if (lilv_nodes_contains(atom_supports, _world.midi_MidiEvent)) {
+                                       flags |= PORT_MIDI;
+                               }
+                               if (lilv_nodes_contains(atom_supports, _world.time_Position)) {
+                                       flags |= PORT_POSITION;
+                               }
+                       }
+                       LilvNodes* min_size_v = lilv_port_get_value(_impl->plugin, port, _world.rsz_minimumSize);
+                       LilvNode* min_size = min_size_v ? lilv_nodes_get_first(min_size_v) : NULL;
+                       if (min_size && lilv_node_is_int(min_size)) {
+                               minimumSize = lilv_node_as_int(min_size);
+                       }
+                       lilv_nodes_free(min_size_v);
+                       lilv_nodes_free(buffer_types);
+                       lilv_nodes_free(atom_supports);
+               } else {
+                       error << string_compose(
+                               "LV2: \"%1\" port %2 has no known data type",
+                               lilv_node_as_string(_impl->name), i) << endmsg;
+                       throw failed_constructor();
+               }
+
+               _port_flags.push_back(flags);
+               _port_minimumSize.push_back(minimumSize);
+       }
 
        _control_data = new float[num_ports];
        _shadow_data  = new float[num_ports];
        _defaults     = new float[num_ports];
+       _ev_buffers   = new LV2_Evbuf*[num_ports];
+       memset(_ev_buffers, 0, sizeof(LV2_Evbuf*) * num_ports);
+
+       const bool     latent        = lilv_plugin_has_latency(plugin);
+       const uint32_t latency_index = (latent)
+               ? lilv_plugin_get_latency_port_index(plugin)
+               : 0;
+
+       // Build an array of pointers to special parameter buffers
+       void*** params = new void**[num_ports];
+       for (uint32_t i = 0; i < num_ports; ++i) {
+               params[i] = NULL;
+       }
+       _impl->designated_input (LV2_TIME__beatsPerMinute, params, (void**)&_bpm_control_port);
+       _impl->designated_input (LV2_CORE__freeWheeling, params, (void**)&_freewheel_control_port);
 
        for (uint32_t i = 0; i < num_ports; ++i) {
                const LilvPort* port = lilv_plugin_get_port_by_index(plugin, i);
@@ -237,26 +503,31 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
                        LilvNode* def;
                        lilv_port_get_range(plugin, port, &def, NULL, NULL);
                        _defaults[i] = def ? lilv_node_as_float(def) : 0.0f;
-                       if (lilv_port_has_property (plugin, port, _world.srate)) {
+                       if (lilv_port_has_property (plugin, port, _world.lv2_sampleRate)) {
                                _defaults[i] *= _session.frame_rate ();
                        }
                        lilv_node_free(def);
 
                        lilv_instance_connect_port(_impl->instance, i, &_control_data[i]);
 
-                       if (latent && ( i == latency_port) ) {
+                       if (latent && i == latency_index) {
                                _latency_control_port  = &_control_data[i];
                                *_latency_control_port = 0;
                        }
 
                        if (parameter_is_input(i)) {
                                _shadow_data[i] = default_value(i);
+                               if (params[i]) {
+                                       *params[i] = (void*)&_shadow_data[i];
+                               }
                        }
                } else {
                        _defaults[i] = 0.0f;
                }
        }
 
+       delete[] params;
+
        LilvUIs* uis = lilv_plugin_get_uis(plugin);
        if (lilv_uis_size(uis) > 0) {
 #ifdef HAVE_SUIL
@@ -266,7 +537,7 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
                        const LilvNode* this_ui_type = NULL;
                        if (lilv_ui_is_supported(this_ui,
                                                 suil_ui_supported,
-                                                _world.gtk_gui,
+                                                _world.ui_GtkUI,
                                                 &this_ui_type)) {
                                // TODO: Multiple UI support
                                _impl->ui      = this_ui;
@@ -278,9 +549,9 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
                // Look for Gtk native UI
                LILV_FOREACH(uis, i, uis) {
                        const LilvUI* ui = lilv_uis_get(uis, i);
-                       if (lilv_ui_is_a(ui, _world.gtk_gui)) {
+                       if (lilv_ui_is_a(ui, _world.ui_GtkUI)) {
                                _impl->ui      = ui;
-                               _impl->ui_type = _world.gtk_gui;
+                               _impl->ui_type = _world.ui_GtkUI;
                                break;
                        }
                }
@@ -290,15 +561,16 @@ LV2Plugin::init(void* c_plugin, framecnt_t rate)
                if (!_impl->ui) {
                        LILV_FOREACH(uis, i, uis) {
                                const LilvUI* ui = lilv_uis_get(uis, i);
-                               if (lilv_ui_is_a(ui, _world.external_gui)) {
+                               if (lilv_ui_is_a(ui, _world.ui_external)) {
                                        _impl->ui      = ui;
-                                       _impl->ui_type = _world.external_gui;
+                                       _impl->ui_type = _world.ui_external;
                                        break;
                                }
                        }
                }
        }
 
+       allocate_atom_event_buffers();
        latency_compute_run();
 }
 
@@ -313,8 +585,26 @@ LV2Plugin::~LV2Plugin ()
        lilv_node_free(_impl->name);
        lilv_node_free(_impl->author);
 
+       free(_features);
+       free(_make_path_feature.data);
+       free(_work_schedule_feature.data);
+
+       delete _to_ui;
+       delete _from_ui;
+       delete _worker;
+
+       if (_atom_ev_buffers) {
+               LV2_Evbuf**  b = _atom_ev_buffers;
+               while (*b) {
+                       free(*b);
+                       b++;
+               }
+               free(_atom_ev_buffers);
+       }
+
        delete [] _control_data;
        delete [] _shadow_data;
+       delete [] _ev_buffers;
 }
 
 bool
@@ -323,7 +613,27 @@ LV2Plugin::is_external_ui() const
        if (!_impl->ui) {
                return false;
        }
-       return lilv_ui_is_a(_impl->ui, _world.external_gui);
+       return lilv_ui_is_a(_impl->ui, _world.ui_external);
+}
+
+bool
+LV2Plugin::ui_is_resizable () const
+{
+       const LilvNode* s   = lilv_ui_get_uri(_impl->ui);
+       LilvNode*       p   = lilv_new_uri(_world.world, LV2_CORE__optionalFeature);
+       LilvNode*       fs  = lilv_new_uri(_world.world, LV2_UI__fixedSize);
+       LilvNode*       nrs = lilv_new_uri(_world.world, LV2_UI__noUserResize);
+
+       LilvNodes* fs_matches = lilv_world_find_nodes(_world.world, s, p, fs);
+       LilvNodes* nrs_matches = lilv_world_find_nodes(_world.world, s, p, nrs);
+
+       lilv_nodes_free(nrs_matches);
+       lilv_nodes_free(fs_matches);
+       lilv_node_free(nrs);
+       lilv_node_free(fs);
+       lilv_node_free(p);
+
+       return !fs_matches && !nrs_matches;
 }
 
 string
@@ -386,6 +696,18 @@ LV2Plugin::port_symbol(uint32_t index) const
        return lilv_node_as_string(sym);
 }
 
+uint32_t
+LV2Plugin::port_index (const char* symbol) const
+{
+       const map<string, uint32_t>::const_iterator i = _port_indices.find(symbol);
+       if (i != _port_indices.end()) {
+               return  i->second;
+       } else {
+               warning << string_compose(_("LV2: Unknown port %1"), symbol) << endmsg;
+               return (uint32_t)-1;
+       }
+}
+
 void
 LV2Plugin::set_parameter(uint32_t which, float val)
 {
@@ -393,6 +715,10 @@ LV2Plugin::set_parameter(uint32_t which, float val)
                            "%1 set parameter %2 to %3\n", name(), which, val));
 
        if (which < lilv_plugin_get_num_ports(_impl->plugin)) {
+               if (get_parameter (which) == val) {
+                       return;
+               }
+
                _shadow_data[which] = val;
        } else {
                warning << string_compose(
@@ -415,6 +741,36 @@ LV2Plugin::get_parameter(uint32_t which) const
        return 0.0f;
 }
 
+std::string
+LV2Plugin::get_docs() const
+{
+       LilvNodes* comments = lilv_plugin_get_value(_impl->plugin, _world.rdfs_comment);
+       if (comments) {
+               const std::string docs(lilv_node_as_string(lilv_nodes_get_first(comments)));
+               lilv_nodes_free(comments);
+               return docs;
+       }
+
+       return "";
+}
+
+std::string
+LV2Plugin::get_parameter_docs(uint32_t which) const
+{
+       LilvNodes* comments = lilv_port_get_value(
+               _impl->plugin,
+               lilv_plugin_get_port_by_index(_impl->plugin, which),
+               _world.rdfs_comment);
+
+       if (comments) {
+               const std::string docs(lilv_node_as_string(lilv_nodes_get_first(comments)));
+               lilv_nodes_free(comments);
+               return docs;
+       }
+
+       return "";
+}
+
 uint32_t
 LV2Plugin::nth_parameter(uint32_t n, bool& ok) const
 {
@@ -432,166 +788,74 @@ LV2Plugin::nth_parameter(uint32_t n, bool& ok) const
 }
 
 const void*
-LV2Plugin::extension_data (const char* uri) const
+LV2Plugin::extension_data(const char* uri) const
 {
        return lilv_instance_get_extension_data(_impl->instance, uri);
 }
 
-void*
-LV2Plugin::c_plugin ()
+const void*
+LV2Plugin::c_plugin()
 {
        return _impl->plugin;
 }
 
-void*
-LV2Plugin::c_ui ()
+const void*
+LV2Plugin::c_ui()
 {
-       return (void*)_impl->ui;
+       return (const void*)_impl->ui;
 }
 
-void*
-LV2Plugin::c_ui_type ()
+const void*
+LV2Plugin::c_ui_type()
 {
-       return (void*)_impl->ui_type;
+       return (const void*)_impl->ui_type;
 }
 
+/** Directory for all plugin state. */
 const std::string
-LV2Plugin::state_dir() const
+LV2Plugin::plugin_dir() const
 {
-       return Glib::build_filename(_session.plugins_dir(),
-                                   _insert_id.to_s());
+       return Glib::build_filename(_session.plugins_dir(), _insert_id.to_s());
 }
 
-int
-LV2Plugin::lv2_state_store_callback(LV2_State_Handle handle,
-                                    uint32_t         key,
-                                    const void*      value,
-                                    size_t           size,
-                                    uint32_t         type,
-                                    uint32_t         flags)
+/** Directory for files created by the plugin (except during save). */
+const std::string
+LV2Plugin::scratch_dir() const
 {
-       DEBUG_TRACE(DEBUG::LV2, string_compose(
-                           "state store %1 (size: %2, type: %3, flags: %4)\n",
-                           _uri_map.id_to_uri(NULL, key),
-                           size,
-                           _uri_map.id_to_uri(NULL, type),
-                           flags));
-
-       LV2State* state = (LV2State*)handle;
-       state->add_uri(key,  _uri_map.id_to_uri(NULL, key));
-       state->add_uri(type, _uri_map.id_to_uri(NULL, type));
-
-       if (type == _state_path_type) {
-               const LV2Plugin&    me = state->plugin;
-               LV2_State_Map_Path* mp = (LV2_State_Map_Path*)me._map_path_feature.data;
-               return state->add_value(
-                       key,
-                       lv2_state_abstract_path(mp->handle, (const char*)value),
-                       size, type, flags);
-       } else if ((flags & LV2_STATE_IS_POD) && (flags & LV2_STATE_IS_PORTABLE)) {
-               return state->add_value(key, value, size, type, flags);
-       } else {
-               PBD::warning << "LV2 plugin attempted to store non-portable property." << endl;
-               return -1;
-       }
+       return Glib::build_filename(plugin_dir(), "scratch");
 }
 
-const void*
-LV2Plugin::lv2_state_retrieve_callback(LV2_State_Handle host_data,
-                                       uint32_t         key,
-                                       size_t*          size,
-                                       uint32_t*        type,
-                                       uint32_t*        flags)
-{
-       LV2State* state = (LV2State*)host_data;
-       LV2State::Values::const_iterator i = state->values.find(key);
-       if (i == state->values.end()) {
-               warning << "LV2 plugin attempted to retrieve nonexistent key: "
-                       << _uri_map.id_to_uri(NULL, key) << endmsg;
-               return NULL;
-       }
-       *size  = i->second.size;
-       *type  = i->second.type;
-       *flags = LV2_STATE_IS_POD | LV2_STATE_IS_PORTABLE;
-       DEBUG_TRACE(DEBUG::LV2, string_compose(
-                           "state retrieve %1 = %2 (size: %3, type: %4)\n",
-                           _uri_map.id_to_uri(NULL, key),
-                           i->second.value, *size, *type));
-       if (*type == _state_path_type) {
-               const LV2Plugin&    me = state->plugin;
-               LV2_State_Map_Path* mp = (LV2_State_Map_Path*)me._map_path_feature.data;
-               return lv2_state_absolute_path(mp->handle, (const char*)i->second.value);
-       } else {
-               return i->second.value;
-       }
-}
-
-char*
-LV2Plugin::lv2_state_abstract_path(LV2_State_Map_Path_Handle handle,
-                                   const char*               absolute_path)
+/** Directory for snapshots of files in the scratch directory. */
+const std::string
+LV2Plugin::file_dir() const
 {
-       LV2Plugin* me = (LV2Plugin*)handle;
-       if (me->_insert_id == PBD::ID("0")) {
-               return g_strdup(absolute_path);
-       }
-
-       const std::string state_dir = me->state_dir();
-
-       char* ret = NULL;
-       if (strncmp(absolute_path, state_dir.c_str(), state_dir.length())) {
-               // Path outside state directory, make symbolic link
-               const std::string       name = Glib::path_get_basename(absolute_path);
-               const std::string       path = Glib::build_filename(state_dir, name);
-               Gio::File::create_for_path(path)->make_symbolic_link(absolute_path);
-               ret = g_strndup(path.c_str(), path.length());
-       } else {
-               // Path inside the state directory, return relative path
-               const std::string path(absolute_path + state_dir.length() + 1);
-               ret = g_strndup(path.c_str(), path.length());
-       }
-
-       DEBUG_TRACE(DEBUG::LV2, string_compose("abstract path %1 => %2\n",
-                                              absolute_path, ret));
-
-       return ret;
+       return Glib::build_filename(plugin_dir(), "files");
 }
 
-char*
-LV2Plugin::lv2_state_absolute_path(LV2_State_Map_Path_Handle handle,
-                                   const char*               abstract_path)
+/** Directory to save state snapshot version @c num into. */
+const std::string
+LV2Plugin::state_dir(unsigned num) const
 {
-       LV2Plugin* me = (LV2Plugin*)handle;
-       if (me->_insert_id == PBD::ID("0")) {
-               return g_strdup(abstract_path);
-       }
-
-       char* ret = NULL;
-       if (g_path_is_absolute(abstract_path)) {
-               ret = g_strdup(abstract_path);
-       } else {
-               const std::string apath(abstract_path);
-               const std::string path = Glib::build_filename(me->state_dir(), apath);
-               ret = g_strndup(path.c_str(), path.length());
-       }
-
-       DEBUG_TRACE(DEBUG::LV2, string_compose("absolute path %1 => %2\n",
-                                              abstract_path, ret));
-
-       return ret;
+       return Glib::build_filename(plugin_dir(), string_compose("state%1", num));
 }
 
+/** Implementation of state:makePath for files created at instantiation time.
+ * Note this is not used for files created at save time (Lilv deals with that).
+ */
 char*
 LV2Plugin::lv2_state_make_path(LV2_State_Make_Path_Handle handle,
                                const char*                path)
 {
        LV2Plugin* me = (LV2Plugin*)handle;
        if (me->_insert_id == PBD::ID("0")) {
+               warning << string_compose(
+                       "File path \"%1\" requested but LV2 %2 has no insert ID",
+                       path, me->name()) << endmsg;
                return g_strdup(path);
        }
 
-       const std::string abs_path = Glib::build_filename(me->state_dir(), path);
+       const std::string abs_path = Glib::build_filename(me->scratch_dir(), path);
        const std::string dirname  = Glib::path_get_dirname(abs_path);
-
        g_mkdir_with_parents(dirname.c_str(), 0744);
 
        DEBUG_TRACE(DEBUG::LV2, string_compose("new file path %1 => %2\n",
@@ -604,9 +868,10 @@ static void
 remove_directory(const std::string& path)
 {
        if (!Glib::file_test(path, Glib::FILE_TEST_IS_DIR)) {
+               warning << string_compose("\"%1\" is not a directory", path) << endmsg;
                return;
        }
-       
+
        Glib::RefPtr<Gio::File>           dir = Gio::File::create_for_path(path);
        Glib::RefPtr<Gio::FileEnumerator> e   = dir->enumerate_children();
        Glib::RefPtr<Gio::FileInfo>       fi;
@@ -640,41 +905,42 @@ LV2Plugin::add_state(XMLNode* root) const
        }
 
        if (_has_state_interface) {
-               // Create state directory for this plugin instance
-               cerr << "Create statefile name from ID " << _insert_id << endl;
-               const std::string state_filename = _insert_id.to_s() + ".rdff";
-               const std::string state_path     = Glib::build_filename(
-                       _session.plugins_dir(), state_filename);
-
-               cout << "Saving LV2 plugin state to " << state_path << endl;
-
-               // Get LV2 State extension data from plugin instance
-               LV2_State_Interface* state_iface = (LV2_State_Interface*)extension_data(
-                       LV2_STATE_INTERFACE_URI);
-               if (!state_iface) {
-                       warning << string_compose(
-                           _("Plugin \"%1\% failed to return LV2 state interface"),
-                           unique_id());
-                       return;
+               // Provisionally increment state version and create directory
+               const std::string new_dir = state_dir(++_state_version);
+               g_mkdir_with_parents(new_dir.c_str(), 0744);
+
+               LilvState* state = lilv_state_new_from_instance(
+                       _impl->plugin,
+                       _impl->instance,
+                       _uri_map.urid_map(),
+                       scratch_dir().c_str(),
+                       file_dir().c_str(),
+                       _session.externals_dir().c_str(),
+                       new_dir.c_str(),
+                       NULL,
+                       const_cast<LV2Plugin*>(this),
+                       0,
+                       NULL);
+
+               if (!_impl->state || !lilv_state_equals(state, _impl->state)) {
+                       lilv_state_save(_world.world,
+                                       _uri_map.urid_map(),
+                                       _uri_map.urid_unmap(),
+                                       state,
+                                       NULL,
+                                       new_dir.c_str(),
+                                       "state.ttl");
+
+                       lilv_state_free(_impl->state);
+                       _impl->state = state;
+               } else {
+                       // State is identical, decrement version and nuke directory
+                       lilv_state_free(state);
+                       remove_directory(new_dir);
+                       --_state_version;
                }
 
-               // Remove old state directory (FIXME: should this be preserved?)
-               remove_directory(state_dir());
-
-               // Save plugin state to state object
-               LV2State state(*this, _uri_map);
-               state_iface->save(_impl->instance->lv2_handle,
-                                 &LV2Plugin::lv2_state_store_callback,
-                                 &state,
-                                 LV2_STATE_IS_POD|LV2_STATE_IS_PORTABLE,
-                                 NULL);
-
-               // Write state object to RDFF file
-               RDFF file = rdff_open(state_path.c_str(), true);
-               state.write(file);
-               rdff_close(file);
-
-               root->add_property("state-file", state_filename);
+               root->add_property("state-dir", string_compose("state%1", _state_version));
        }
 }
 
@@ -688,69 +954,144 @@ get_value(LilvWorld* world, const LilvNode* subject, const LilvNode* predicate)
 void
 LV2Plugin::find_presets()
 {
-       LilvNode* dc_title       = lilv_new_uri(_world.world, NS_DC   "title");
-       LilvNode* pset_hasPreset = lilv_new_uri(_world.world, NS_PSET "hasPreset");
+       LilvNode* lv2_appliesTo = lilv_new_uri(_world.world, LV2_CORE__appliesTo);
+       LilvNode* pset_Preset   = lilv_new_uri(_world.world, LV2_PRESETS__Preset);
+       LilvNode* rdfs_label    = lilv_new_uri(_world.world, LILV_NS_RDFS "label");
 
-       LilvNodes* presets = lilv_plugin_get_value(_impl->plugin, pset_hasPreset);
+       LilvNodes* presets = lilv_plugin_get_related(_impl->plugin, pset_Preset);
        LILV_FOREACH(nodes, i, presets) {
                const LilvNode* preset = lilv_nodes_get(presets, i);
-               const LilvNode* name   = get_value(_world.world, preset, dc_title);
+               lilv_world_load_resource(_world.world, preset);
+               const LilvNode* name = get_value(_world.world, preset, rdfs_label);
                if (name) {
                        _presets.insert(std::make_pair(lilv_node_as_string(preset),
-                                                      PresetRecord(
-                                                          lilv_node_as_string(preset),
-                                                          lilv_node_as_string(name))));
+                                                      Plugin::PresetRecord(
+                                                              lilv_node_as_string(preset),
+                                                              lilv_node_as_string(name))));
                } else {
                        warning << string_compose(
-                           _("Plugin \"%1\% preset \"%2%\" is missing a dc:title\n"),
-                           unique_id(), lilv_node_as_string(preset));
+                           _("Plugin \"%1\% preset \"%2%\" is missing a label\n"),
+                           lilv_node_as_string(lilv_plugin_get_uri(_impl->plugin)),
+                           lilv_node_as_string(preset)) << endmsg;
                }
        }
        lilv_nodes_free(presets);
 
-       lilv_node_free(pset_hasPreset);
-       lilv_node_free(dc_title);
+       lilv_node_free(rdfs_label);
+       lilv_node_free(pset_Preset);
+       lilv_node_free(lv2_appliesTo);
+}
+
+static void
+set_port_value(const char* port_symbol,
+               void*       user_data,
+               const void* value,
+               uint32_t    /*size*/,
+               uint32_t    type)
+{
+       LV2Plugin* self = (LV2Plugin*)user_data;
+       if (type != 0 && type != self->_uri_map.uri_to_id(LV2_ATOM__Float)) {
+               return;  // TODO: Support non-float ports
+       }
+
+       const uint32_t port_index = self->port_index(port_symbol);
+       if (port_index != (uint32_t)-1) {
+               self->set_parameter(port_index, *(const float*)value);
+       }
 }
 
 bool
 LV2Plugin::load_preset(PresetRecord r)
 {
-       Plugin::load_preset(r);
-
-       LilvNode* lv2_port   = lilv_new_uri(_world.world, NS_LV2 "port");
-       LilvNode* lv2_symbol = lilv_new_uri(_world.world, NS_LV2 "symbol");
-       LilvNode* pset_value = lilv_new_uri(_world.world, NS_PSET "value");
-       LilvNode* preset     = lilv_new_uri(_world.world, r.uri.c_str());
-
-       LilvNodes* ports = lilv_world_find_nodes(_world.world, preset, lv2_port, NULL);
-       LILV_FOREACH(nodes, i, ports) {
-               const LilvNode* port   = lilv_nodes_get(ports, i);
-               const LilvNode* symbol = get_value(_world.world, port, lv2_symbol);
-               const LilvNode* value  = get_value(_world.world, port, pset_value);
-               if (value && lilv_node_is_float(value)) {
-                       set_parameter(_port_indices[lilv_node_as_string(symbol)],
-                                     lilv_node_as_float(value));
-               }
+       LilvWorld* world = _world.world;
+       LilvNode*  pset  = lilv_new_uri(world, r.uri.c_str());
+       LilvState* state = lilv_state_new_from_world(world, _uri_map.urid_map(), pset);
+
+       if (state) {
+               lilv_state_restore(state, _impl->instance, set_port_value, this, 0, NULL);
+               lilv_state_free(state);
        }
-       lilv_nodes_free(ports);
 
-       lilv_node_free(preset);
-       lilv_node_free(pset_value);
-       lilv_node_free(lv2_symbol);
-       lilv_node_free(lv2_port);
+       lilv_node_free(pset);
+       return state;
+}
 
-       return true;
+const void*
+ARDOUR::lv2plugin_get_port_value(const char* port_symbol,
+                                 void*       user_data,
+                                 uint32_t*   size,
+                                 uint32_t*   type)
+{
+       LV2Plugin *plugin = (LV2Plugin *) user_data;
+
+       uint32_t index = plugin->port_index(port_symbol);
+       if (index != (uint32_t) -1) {
+               if (plugin->parameter_is_input(index) && plugin->parameter_is_control(index)) {
+                       float *value;
+                       *size = sizeof(float);
+                       *type = plugin->_uri_map.uri_to_id(LV2_ATOM__Float);
+                       value = &plugin->_shadow_data[index];
+
+                       return value;
+               }
+       }
+
+       *size = *type = 0;
+       return NULL;
 }
 
+
 std::string
-LV2Plugin::do_save_preset(string /*name*/)
+LV2Plugin::do_save_preset(string name)
 {
-       return "";
+       const string base_name = legalize_for_uri(name);
+       const string file_name = base_name + ".ttl";
+       const string bundle    = Glib::build_filename(
+               Glib::get_home_dir(),
+               Glib::build_filename(".lv2", base_name + ".lv2"));
+
+       LilvState* state = lilv_state_new_from_instance(
+               _impl->plugin,
+               _impl->instance,
+               _uri_map.urid_map(),
+               scratch_dir().c_str(),                   // file_dir
+               bundle.c_str(),                          // copy_dir
+               bundle.c_str(),                          // link_dir
+               bundle.c_str(),                          // save_dir
+               lv2plugin_get_port_value,                // get_value
+               (void*)this,                             // user_data
+               LV2_STATE_IS_POD|LV2_STATE_IS_PORTABLE,  // flags
+               _features                                // features
+       );
+
+       lilv_state_set_label(state, name.c_str());
+       lilv_state_save(
+               _world.world,           // world
+               _uri_map.urid_map(),    // map
+               _uri_map.urid_unmap(),  // unmap
+               state,                  // state
+               NULL,                   // uri (NULL = use file URI)
+               bundle.c_str(),         // dir
+               file_name.c_str()       // filename
+       );
+
+       lilv_state_free(state);
+
+       return Glib::filename_to_uri(Glib::build_filename(bundle, file_name));
 }
 
 void
-LV2Plugin::do_remove_preset(string /*name*/)
-{}
+LV2Plugin::do_remove_preset(string name)
+{
+       string preset_file = Glib::build_filename(
+               Glib::get_home_dir(),
+               Glib::build_filename(
+                       Glib::build_filename(".lv2", "presets"),
+                       name + ".ttl"
+               )
+       );
+       unlink(preset_file.c_str());
+}
 
 bool
 LV2Plugin::has_editor() const
@@ -758,6 +1099,117 @@ LV2Plugin::has_editor() const
        return _impl->ui != NULL;
 }
 
+bool
+LV2Plugin::has_message_output() const
+{
+       for (uint32_t i = 0; i < num_ports(); ++i) {
+               if ((_port_flags[i] & PORT_SEQUENCE) &&
+                   (_port_flags[i] & PORT_OUTPUT)) {
+                       return true;
+               }
+       }
+       return false;
+}
+
+bool
+LV2Plugin::write_to(RingBuffer<uint8_t>* dest,
+                    uint32_t             index,
+                    uint32_t             protocol,
+                    uint32_t             size,
+                    const uint8_t*       body)
+{
+       const uint32_t buf_size = sizeof(UIMessage) + size;
+       uint8_t        buf[buf_size];
+
+       UIMessage* msg = (UIMessage*)buf;
+       msg->index    = index;
+       msg->protocol = protocol;
+       msg->size     = size;
+       memcpy(msg + 1, body, size);
+
+       return (dest->write(buf, buf_size) == buf_size);
+}
+
+bool
+LV2Plugin::write_from_ui(uint32_t       index,
+                         uint32_t       protocol,
+                         uint32_t       size,
+                         const uint8_t* body)
+{
+       if (!_from_ui) {
+               _from_ui = new RingBuffer<uint8_t>(
+                       _session.engine().raw_buffer_size(DataType::MIDI) * NBUFS);
+       }
+
+       if (!write_to(_from_ui, index, protocol, size, body)) {
+               error << "Error writing from UI to plugin" << endmsg;
+               return false;
+       }
+       return true;
+}
+
+bool
+LV2Plugin::write_to_ui(uint32_t       index,
+                       uint32_t       protocol,
+                       uint32_t       size,
+                       const uint8_t* body)
+{
+       if (!write_to(_to_ui, index, protocol, size, body)) {
+               error << "Error writing from plugin to UI" << endmsg;
+               return false;
+       }
+       return true;
+}
+
+void
+LV2Plugin::enable_ui_emmission()
+{
+       if (!_to_ui) {
+               _to_ui = new RingBuffer<uint8_t>(
+                       _session.engine().raw_buffer_size(DataType::MIDI) * NBUFS);
+       }
+}
+
+void
+LV2Plugin::emit_to_ui(void* controller, UIMessageSink sink)
+{
+       if (!_to_ui) {
+               return;
+       }
+
+       uint32_t read_space = _to_ui->read_space();
+       while (read_space > sizeof(UIMessage)) {
+               UIMessage msg;
+               if (_to_ui->read((uint8_t*)&msg, sizeof(msg)) != sizeof(msg)) {
+                       error << "Error reading from Plugin=>UI RingBuffer" << endmsg;
+                       break;
+               }
+               uint8_t body[msg.size];
+               if (_to_ui->read(body, msg.size) != msg.size) {
+                       error << "Error reading from Plugin=>UI RingBuffer" << endmsg;
+                       break;
+               }
+
+               sink(controller, msg.index, msg.size, msg.protocol, body);
+
+               read_space -= sizeof(msg) + msg.size;
+       }
+}
+
+int
+LV2Plugin::work(uint32_t size, const void* data)
+{
+       return _impl->work_iface->work(
+               _impl->instance->lv2_handle, work_respond, this, size, data);
+}
+
+int
+LV2Plugin::work_response(uint32_t size, const void* data)
+{
+       return _impl->work_iface->work_response(
+               _impl->instance->lv2_handle, size, data);
+}
+
 void
 LV2Plugin::set_insert_info(const PluginInsert* insert)
 {
@@ -781,6 +1233,8 @@ LV2Plugin::set_state(const XMLNode& node, int version)
                return -1;
        }
 
+#ifndef NO_PLUGIN_STATE
+
        if (version < 3000) {
                nodes = node.children("port");
        } else {
@@ -817,34 +1271,26 @@ LV2Plugin::set_state(const XMLNode& node, int version)
                set_parameter(port_id, atof(value));
        }
 
-       if ((prop = node.property("state-file")) != 0) {
-               std::string state_path = Glib::build_filename(_session.plugins_dir(),
-                                                             prop->value());
-
-               cout << "LV2 state path " << state_path << endl;
-
-               // Get LV2 State extension data from plugin instance
-               LV2_State_Interface* state_iface = (LV2_State_Interface*)extension_data(
-                       LV2_STATE_INTERFACE_URI);
-               if (state_iface) {
-                       cout << "Loading LV2 state from " << state_path << endl;
-                       RDFF     file = rdff_open(state_path.c_str(), false);
-                       LV2State state(*this, _uri_map);
-                       state.read(file);
-                       state_iface->restore(_impl->instance->lv2_handle,
-                                            &LV2Plugin::lv2_state_retrieve_callback,
-                                            &state,
-                                            LV2_STATE_IS_POD|LV2_STATE_IS_PORTABLE,
-                                            NULL);
-                       rdff_close(file);
-               } else {
-                       warning << string_compose(
-                           _("Plugin \"%1\% failed to return LV2 state interface"),
-                           unique_id());
+       _state_version = 0;
+       if ((prop = node.property("state-dir")) != 0) {
+               if (sscanf(prop->value().c_str(), "state%u", &_state_version) != 1) {
+                       error << string_compose(
+                               "LV2: failed to parse state version from \"%1\"",
+                               prop->value()) << endmsg;
                }
+
+               std::string state_file = Glib::build_filename(
+                       plugin_dir(),
+                       Glib::build_filename(prop->value(), "state.ttl"));
+
+               LilvState* state = lilv_state_new_from_file(
+                       _world.world, _uri_map.urid_map(), NULL, state_file.c_str());
+
+               lilv_state_restore(state, _impl->instance, NULL, NULL, 0, NULL);
        }
 
        latency_compute_run();
+#endif
 
        return Plugin::set_state(node, version);
 }
@@ -857,10 +1303,10 @@ LV2Plugin::get_parameter_descriptor(uint32_t which, ParameterDescriptor& desc) c
        LilvNode *def, *min, *max;
        lilv_port_get_range(_impl->plugin, port, &def, &min, &max);
 
-       desc.integer_step = lilv_port_has_property(_impl->plugin, port, _world.integer);
-       desc.toggled      = lilv_port_has_property(_impl->plugin, port, _world.toggled);
-       desc.logarithmic  = lilv_port_has_property(_impl->plugin, port, _world.logarithmic);
-       desc.sr_dependent = lilv_port_has_property(_impl->plugin, port, _world.srate);
+       desc.integer_step = lilv_port_has_property(_impl->plugin, port, _world.lv2_integer);
+       desc.toggled      = lilv_port_has_property(_impl->plugin, port, _world.lv2_toggled);
+       desc.logarithmic  = lilv_port_has_property(_impl->plugin, port, _world.ext_logarithmic);
+       desc.sr_dependent = lilv_port_has_property(_impl->plugin, port, _world.lv2_sampleRate);
        desc.label        = lilv_node_as_string(lilv_port_get_name(_impl->plugin, port));
        desc.lower        = min ? lilv_node_as_float(min) : 0.0f;
        desc.upper        = max ? lilv_node_as_float(max) : 1.0f;
@@ -868,7 +1314,7 @@ LV2Plugin::get_parameter_descriptor(uint32_t which, ParameterDescriptor& desc) c
                desc.lower *= _session.frame_rate ();
                desc.upper *= _session.frame_rate ();
        }
-               
+
        desc.min_unbound  = false; // TODO: LV2 extension required
        desc.max_unbound  = false; // TODO: LV2 extension required
 
@@ -883,6 +1329,8 @@ LV2Plugin::get_parameter_descriptor(uint32_t which, ParameterDescriptor& desc) c
                desc.largestep = delta / 10.0f;
        }
 
+       desc.enumeration = lilv_port_has_property(_impl->plugin, port, _world.lv2_enumeration);
+
        lilv_node_free(def);
        lilv_node_free(min);
        lilv_node_free(max);
@@ -894,6 +1342,27 @@ string
 LV2Plugin::describe_parameter(Evoral::Parameter which)
 {
        if (( which.type() == PluginAutomation) && ( which.id() < parameter_count()) ) {
+
+               if (lilv_port_has_property(_impl->plugin,
+                                       lilv_plugin_get_port_by_index(_impl->plugin, which.id()), _world.ext_notOnGUI)) {
+                       return X_("hidden");
+               }
+
+               if (lilv_port_has_property(_impl->plugin,
+                                       lilv_plugin_get_port_by_index(_impl->plugin, which.id()), _world.lv2_freewheeling)) {
+                       return X_("hidden");
+               }
+
+               if (lilv_port_has_property(_impl->plugin,
+                                       lilv_plugin_get_port_by_index(_impl->plugin, which.id()), _world.lv2_sampleRate)) {
+                       return X_("hidden");
+               }
+
+               if (lilv_port_has_property(_impl->plugin,
+                                       lilv_plugin_get_port_by_index(_impl->plugin, which.id()), _world.lv2_reportsLatency)) {
+                       return X_("latency");
+               }
+
                LilvNode* name = lilv_port_get_name(_impl->plugin,
                                                    lilv_plugin_get_port_by_index(_impl->plugin, which.id()));
                string ret(lilv_node_as_string(name));
@@ -961,6 +1430,102 @@ LV2Plugin::cleanup()
        _impl->instance = NULL;
 }
 
+void
+LV2Plugin::allocate_atom_event_buffers()
+{
+       /* reserve local scratch buffers for ATOM event-queues */
+       const LilvPlugin* p = _impl->plugin;
+
+       /* count non-MIDI atom event-ports
+        * TODO: nicely ask drobilla to make a lilv_ call for that
+        */
+       int count_atom_out = 0;
+       int count_atom_in = 0;
+       int minimumSize = 32768; // TODO use a per-port minimum-size
+       for (uint32_t i = 0; i < lilv_plugin_get_num_ports(p); ++i) {
+               const LilvPort* port  = lilv_plugin_get_port_by_index(p, i);
+               if (lilv_port_is_a(p, port, _world.atom_AtomPort)) {
+                       LilvNodes* buffer_types = lilv_port_get_value(
+                               p, port, _world.atom_bufferType);
+                       LilvNodes* atom_supports = lilv_port_get_value(
+                               p, port, _world.atom_supports);
+
+                       if (!lilv_nodes_contains(buffer_types, _world.atom_Sequence)
+                                       || !lilv_nodes_contains(atom_supports, _world.midi_MidiEvent)) {
+                               if (lilv_port_is_a(p, port, _world.lv2_InputPort)) {
+                                       count_atom_in++;
+                               }
+                               if (lilv_port_is_a(p, port, _world.lv2_OutputPort)) {
+                                       count_atom_out++;
+                               }
+                               LilvNodes* min_size_v = lilv_port_get_value(_impl->plugin, port, _world.rsz_minimumSize);
+                               LilvNode* min_size = min_size_v ? lilv_nodes_get_first(min_size_v) : NULL;
+                               if (min_size && lilv_node_is_int(min_size)) {
+                                       minimumSize = std::max(minimumSize, lilv_node_as_int(min_size));
+                               }
+                               lilv_nodes_free(min_size_v);
+                       }
+                       lilv_nodes_free(buffer_types);
+                       lilv_nodes_free(atom_supports);
+               }
+       }
+
+       DEBUG_TRACE(DEBUG::LV2, string_compose("%1 need buffers for %2 atom-in and %3 atom-out event-ports\n",
+                               name(), count_atom_in, count_atom_out));
+
+       const int total_atom_buffers = (count_atom_in + count_atom_out);
+       if (_atom_ev_buffers || total_atom_buffers == 0) {
+               return;
+       }
+
+       DEBUG_TRACE(DEBUG::LV2, string_compose("allocate %1 atom_ev_buffers\n", total_atom_buffers));
+       _atom_ev_buffers = (LV2_Evbuf**) malloc((total_atom_buffers + 1) * sizeof(LV2_Evbuf*));
+       for (int i = 0; i < total_atom_buffers; ++i ) {
+               _atom_ev_buffers[i] = lv2_evbuf_new(minimumSize, LV2_EVBUF_ATOM,
+                               LV2Plugin::urids.atom_Chunk, LV2Plugin::urids.atom_Sequence);
+       }
+       _atom_ev_buffers[total_atom_buffers] = 0;
+       return;
+}
+
+/** Write an ardour position/time/tempo/meter as an LV2 event.
+ * @return true on success.
+ */
+static bool
+write_position(LV2_Atom_Forge*     forge,
+               LV2_Evbuf*          buf,
+               const TempoMetric&  t,
+               Timecode::BBT_Time& bbt,
+               double              speed,
+               framepos_t          position,
+               framecnt_t          offset)
+{
+       uint8_t pos_buf[256];
+       lv2_atom_forge_set_buffer(forge, pos_buf, sizeof(pos_buf));
+       LV2_Atom_Forge_Frame frame;
+       lv2_atom_forge_blank(forge, &frame, 1, LV2Plugin::urids.time_Position);
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_frame, 0);
+       lv2_atom_forge_long(forge, position);
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_speed, 0);
+       lv2_atom_forge_float(forge, speed);
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_barBeat, 0);
+       lv2_atom_forge_float(forge, bbt.beats - 1 +
+                            (bbt.ticks / Timecode::BBT_Time::ticks_per_beat));
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_bar, 0);
+       lv2_atom_forge_long(forge, bbt.bars - 1);
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_beatUnit, 0);
+       lv2_atom_forge_int(forge, t.meter().note_divisor());
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_beatsPerBar, 0);
+       lv2_atom_forge_float(forge, t.meter().divisions_per_bar());
+       lv2_atom_forge_property_head(forge, LV2Plugin::urids.time_beatsPerMinute, 0);
+       lv2_atom_forge_float(forge, t.tempo().beats_per_minute());
+
+       LV2_Evbuf_Iterator    end  = lv2_evbuf_end(buf);
+       const LV2_Atom* const atom = (const LV2_Atom*)pos_buf;
+       return lv2_evbuf_write(&end, offset, 0, atom->type, atom->size,
+                              (const uint8_t*)(atom + 1));
+}
+
 int
 LV2Plugin::connect_and_run(BufferSet& bufs,
        ChanMapping in_map, ChanMapping out_map,
@@ -971,113 +1536,255 @@ LV2Plugin::connect_and_run(BufferSet& bufs,
 
        cycles_t then = get_cycles();
 
+       TempoMap&               tmap     = _session.tempo_map();
+       Metrics::const_iterator metric_i = tmap.metrics_end();
+       TempoMetric             tmetric  = tmap.metric_at(_session.transport_frame(), &metric_i);
+
+       if (_freewheel_control_port) {
+               *_freewheel_control_port = _session.engine().freewheeling();
+       }
+
+       if (_bpm_control_port) {
+               *_bpm_control_port = tmetric.tempo().beats_per_minute();
+       }
+
        ChanCount bufs_count;
        bufs_count.set(DataType::AUDIO, 1);
        bufs_count.set(DataType::MIDI, 1);
        BufferSet& silent_bufs  = _session.get_silent_buffers(bufs_count);
-       BufferSet& scratch_bufs = _session.get_silent_buffers(bufs_count);
+       BufferSet& scratch_bufs = _session.get_scratch_buffers(bufs_count);
+       uint32_t const num_ports = parameter_count();
+       uint32_t const nil_index = std::numeric_limits<uint32_t>::max();
 
        uint32_t audio_in_index  = 0;
        uint32_t audio_out_index = 0;
        uint32_t midi_in_index   = 0;
        uint32_t midi_out_index  = 0;
-       bool valid;
-       for (uint32_t port_index = 0; port_index < parameter_count(); ++port_index) {
-               if (parameter_is_audio(port_index)) {
-                       if (parameter_is_input(port_index)) {
-                               const uint32_t buf_index = in_map.get(DataType::AUDIO, audio_in_index++, &valid);
-                               lilv_instance_connect_port(_impl->instance, port_index,
-                                                          valid ? bufs.get_audio(buf_index).data(offset)
-                                                                : silent_bufs.get_audio(0).data(offset));
-                       } else if (parameter_is_output(port_index)) {
-                               const uint32_t buf_index = out_map.get(DataType::AUDIO, audio_out_index++, &valid);
-                               //cerr << port_index << " : " << " AUDIO OUT " << buf_index << endl;
-                               lilv_instance_connect_port(_impl->instance, port_index,
-                                                          valid ? bufs.get_audio(buf_index).data(offset)
-                                                                : scratch_bufs.get_audio(0).data(offset));
+       uint32_t atom_port_index = 0;
+       for (uint32_t port_index = 0; port_index < num_ports; ++port_index) {
+               void*     buf   = NULL;
+               uint32_t  index = nil_index;
+               PortFlags flags = _port_flags[port_index];
+               bool      valid = false;
+               if (flags & PORT_AUDIO) {
+                       if (flags & PORT_INPUT) {
+                               index = in_map.get(DataType::AUDIO, audio_in_index++, &valid);
+                               buf = (valid)
+                                       ? bufs.get_audio(index).data(offset)
+                                       : silent_bufs.get_audio(0).data(offset);
+                       } else {
+                               index = out_map.get(DataType::AUDIO, audio_out_index++, &valid);
+                               buf = (valid)
+                                       ? bufs.get_audio(index).data(offset)
+                                       : scratch_bufs.get_audio(0).data(offset);
                        }
-               } else if (parameter_is_midi(port_index)) {
-                       /* FIXME: The checks here for bufs.count().n_midi() > buf_index shouldn't
+               } else if (flags & (PORT_EVENT|PORT_SEQUENCE)) {
+                       /* FIXME: The checks here for bufs.count().n_midi() > index shouldn't
                           be necessary, but the mapping is illegal in some cases.  Ideally
                           that should be fixed, but this is easier...
                        */
-                       if (parameter_is_input(port_index)) {
-                               const uint32_t buf_index = in_map.get(DataType::MIDI, midi_in_index++, &valid);
-                               if (valid && bufs.count().n_midi() > buf_index) {
-                                       lilv_instance_connect_port(_impl->instance, port_index,
-                                                                  bufs.get_lv2_midi(true, buf_index).data());
+                       if (flags & PORT_MIDI) {
+                               if (flags & PORT_INPUT) {
+                                       index = in_map.get(DataType::MIDI, midi_in_index++, &valid);
                                } else {
-                                       lilv_instance_connect_port(_impl->instance, port_index,
-                                                                  silent_bufs.get_lv2_midi(true, 0).data());
+                                       index = out_map.get(DataType::MIDI, midi_out_index++, &valid);
                                }
-                       } else if (parameter_is_output(port_index)) {
-                               const uint32_t buf_index = out_map.get(DataType::MIDI, midi_out_index++, &valid);
-                               if (valid && bufs.count().n_midi() > buf_index) {
-                                       lilv_instance_connect_port(_impl->instance, port_index,
-                                                                  bufs.get_lv2_midi(false, buf_index).data());
-                               } else {
-                                       lilv_instance_connect_port(_impl->instance, port_index,
-                                                                  scratch_bufs.get_lv2_midi(true, 0).data());
+                               if (valid && bufs.count().n_midi() > index) {
+                                       /* Note, ensure_lv2_bufsize() is not RT safe!
+                                        * However free()/alloc() is only called if a
+                                        * plugin requires a rsz:minimumSize buffersize
+                                        * and the existing buffer if smaller.
+                                        */
+                                       bufs.ensure_lv2_bufsize((flags & PORT_INPUT), index, _port_minimumSize[port_index]);
+                                       _ev_buffers[port_index] = bufs.get_lv2_midi(
+                                               (flags & PORT_INPUT), index, (flags & PORT_EVENT));
                                }
+                       } else if ((flags & PORT_POSITION) && (flags & PORT_INPUT)) {
+                               lv2_evbuf_reset(_atom_ev_buffers[atom_port_index], true);
+                               _ev_buffers[port_index] = _atom_ev_buffers[atom_port_index++];
+                               valid                   = true;
                        }
-               } else if (!parameter_is_control(port_index)) {
-                       // Optional port (it'd better be if we've made it this far...)
-                       lilv_instance_connect_port(_impl->instance, port_index, NULL);
+
+                       if (valid && (flags & PORT_INPUT)) {
+                               Timecode::BBT_Time bbt;
+                               if ((flags & PORT_POSITION)) {
+                                       if (_session.transport_frame() != _next_cycle_start ||
+                                           _session.transport_speed() != _next_cycle_speed) {
+                                               // Transport has changed, write position at cycle start
+                                               tmap.bbt_time(_session.transport_frame(), bbt);
+                                               write_position(&_impl->forge, _ev_buffers[port_index],
+                                                              tmetric, bbt, _session.transport_speed(),
+                                                              _session.transport_frame(), 0);
+                                       }
+                               }
+
+                               // Get MIDI iterator range (empty range if no MIDI)
+                               MidiBuffer::iterator m = (index != nil_index)
+                                       ? bufs.get_midi(index).begin()
+                                       : silent_bufs.get_midi(0).end();
+                               MidiBuffer::iterator m_end = (index != nil_index)
+                                       ? bufs.get_midi(index).end()
+                                       : m;
+
+                               // Now merge MIDI and any transport events into the buffer
+                               const uint32_t     type = LV2Plugin::urids.midi_MidiEvent;
+                               const framepos_t   tend = _session.transport_frame() + nframes;
+                               ++metric_i;
+                               while (m != m_end || (metric_i != tmap.metrics_end() &&
+                                                     (*metric_i)->frame() < tend)) {
+                                       MetricSection* metric = (metric_i != tmap.metrics_end())
+                                               ? *metric_i : NULL;
+                                       if (m != m_end && (!metric || metric->frame() > (*m).time())) {
+                                               const Evoral::MIDIEvent<framepos_t> ev(*m, false);
+                                               LV2_Evbuf_Iterator eend = lv2_evbuf_end(_ev_buffers[port_index]);
+                                               lv2_evbuf_write(&eend, ev.time(), 0, type, ev.size(), ev.buffer());
+                                               ++m;
+                                       } else {
+                                               tmetric.set_metric(metric);
+                                               bbt = metric->start();
+                                               write_position(&_impl->forge, _ev_buffers[port_index],
+                                                              tmetric, bbt, _session.transport_speed(),
+                                                              metric->frame(),
+                                                              metric->frame() - _session.transport_frame());
+                                               ++metric_i;
+                                       }
+                               }
+                       } else if (!valid) {
+                               // Nothing we understand or care about, connect to scratch
+                               _ev_buffers[port_index] = silent_bufs.get_lv2_midi(
+                                       (flags & PORT_INPUT), 0, (flags & PORT_EVENT));
+                       }
+                       buf = lv2_evbuf_get_buffer(_ev_buffers[port_index]);
+               } else {
+                       continue;  // Control port, leave buffer alone
+               }
+               lilv_instance_connect_port(_impl->instance, port_index, buf);
+       }
+
+       // Read messages from UI and push into appropriate buffers
+       if (_from_ui) {
+               uint32_t read_space = _from_ui->read_space();
+               while (read_space > sizeof(UIMessage)) {
+                       UIMessage msg;
+                       if (_from_ui->read((uint8_t*)&msg, sizeof(msg)) != sizeof(msg)) {
+                               error << "Error reading from UI=>Plugin RingBuffer" << endmsg;
+                               break;
+                       }
+                       uint8_t body[msg.size];
+                       if (_from_ui->read(body, msg.size) != msg.size) {
+                               error << "Error reading from UI=>Plugin RingBuffer" << endmsg;
+                               break;
+                       }
+                       if (msg.protocol == urids.atom_eventTransfer) {
+                               LV2_Evbuf*            buf  = _ev_buffers[msg.index];
+                               LV2_Evbuf_Iterator    i    = lv2_evbuf_end(buf);
+                               const LV2_Atom* const atom = (const LV2_Atom*)body;
+                               if (!lv2_evbuf_write(&i, nframes, 0, atom->type, atom->size,
+                                               (const uint8_t*)(atom + 1))) {
+                                       error << "Failed to write data to LV2 event buffer\n";
+                               }
+                       } else {
+                               error << "Received unknown message type from UI" << endmsg;
+                       }
+                       read_space -= sizeof(UIMessage) + msg.size;
                }
        }
 
        run(nframes);
 
        midi_out_index = 0;
-       for (uint32_t port_index = 0; port_index < parameter_count(); ++port_index) {
-               if (parameter_is_midi(port_index) && parameter_is_output(port_index)) {
-                       const uint32_t buf_index = out_map.get(DataType::MIDI, midi_out_index++, &valid);
+       for (uint32_t port_index = 0; port_index < num_ports; ++port_index) {
+               PortFlags flags = _port_flags[port_index];
+               bool      valid = false;
+
+               /* TODO ask drobilla about comment
+                * "Make Ardour event buffers generic so plugins can communicate"
+                * in libs/ardour/buffer_set.cc:310
+                *
+                * ideally the user could choose which of the following two modes
+                * to use (e.g. instrument/effect chains  MIDI OUT vs MIDI TRHU).
+                *
+                * This implementation follows the discussion on IRC Mar 16 2013 16:47 UTC
+                * 16:51 < drobilla> rgareus: [..] i.e always replace with MIDI output [of LV2 plugin] if it's there
+                * 16:52 < drobilla> rgareus: That would probably be good enough [..] to make users not complain
+                *                            for quite a while at least ;)
+                */
+               // copy output of LV2 plugin's MIDI port to Ardour MIDI buffers -- MIDI OUT
+               if ((flags & PORT_OUTPUT) && (flags & (PORT_EVENT|PORT_SEQUENCE|PORT_MIDI))) {
+                       const uint32_t buf_index = out_map.get(
+                               DataType::MIDI, midi_out_index++, &valid);
+                       if (valid) {
+                               bufs.forward_lv2_midi(_ev_buffers[port_index], buf_index);
+                       }
+               }
+               // Flush MIDI (write back to Ardour MIDI buffers) -- MIDI THRU
+               else if ((flags & PORT_OUTPUT) && (flags & (PORT_EVENT|PORT_SEQUENCE))) {
+                       const uint32_t buf_index = out_map.get(
+                               DataType::MIDI, midi_out_index++, &valid);
                        if (valid) {
                                bufs.flush_lv2_midi(true, buf_index);
                        }
                }
+
+               // Write messages to UI
+               if (_to_ui && (flags & PORT_OUTPUT) && (flags & (PORT_EVENT|PORT_SEQUENCE))) {
+                       LV2_Evbuf* buf = _ev_buffers[port_index];
+                       for (LV2_Evbuf_Iterator i = lv2_evbuf_begin(buf);
+                            lv2_evbuf_is_valid(i);
+                            i = lv2_evbuf_next(i)) {
+                               uint32_t frames, subframes, type, size;
+                               uint8_t* data;
+                               lv2_evbuf_get(i, &frames, &subframes, &type, &size, &data);
+                               write_to_ui(port_index, urids.atom_eventTransfer,
+                                           size + sizeof(LV2_Atom),
+                                           data - sizeof(LV2_Atom));
+                       }
+               }
        }
 
        cycles_t now = get_cycles();
        set_cycles((uint32_t)(now - then));
 
+       // Update expected transport information for next cycle so we can detect changes
+       _next_cycle_speed = _session.transport_speed();
+       _next_cycle_start = _session.transport_frame() + (nframes * _next_cycle_speed);
+
        return 0;
 }
 
 bool
 LV2Plugin::parameter_is_control(uint32_t param) const
 {
-       const LilvPort* port = lilv_plugin_get_port_by_index(_impl->plugin, param);
-       return lilv_port_is_a(_impl->plugin, port, _world.control_class);
+       assert(param < _port_flags.size());
+       return _port_flags[param] & PORT_CONTROL;
 }
 
 bool
 LV2Plugin::parameter_is_audio(uint32_t param) const
 {
-       const LilvPort* port = lilv_plugin_get_port_by_index(_impl->plugin, param);
-       return lilv_port_is_a(_impl->plugin, port, _world.audio_class);
+       assert(param < _port_flags.size());
+       return _port_flags[param] & PORT_AUDIO;
 }
 
 bool
-LV2Plugin::parameter_is_midi(uint32_t param) const
+LV2Plugin::parameter_is_event(uint32_t param) const
 {
-       const LilvPort* port = lilv_plugin_get_port_by_index(_impl->plugin, param);
-       return lilv_port_is_a(_impl->plugin, port, _world.event_class);
-       //      && lilv_port_supports_event(_impl->plugin, port, _world.midi_class);
+       assert(param < _port_flags.size());
+       return _port_flags[param] & PORT_EVENT;
 }
 
 bool
 LV2Plugin::parameter_is_output(uint32_t param) const
 {
-       const LilvPort* port = lilv_plugin_get_port_by_index(_impl->plugin, param);
-       return lilv_port_is_a(_impl->plugin, port, _world.output_class);
+       assert(param < _port_flags.size());
+       return _port_flags[param] & PORT_OUTPUT;
 }
 
 bool
 LV2Plugin::parameter_is_input(uint32_t param) const
 {
-       const LilvPort* port = lilv_plugin_get_port_by_index(_impl->plugin, param);
-       return lilv_port_is_a(_impl->plugin, port, _world.input_class);
+       assert(param < _port_flags.size());
+       return _port_flags[param] & PORT_INPUT;
 }
 
 void
@@ -1122,13 +1829,21 @@ LV2Plugin::get_scale_points(uint32_t port_index) const
 void
 LV2Plugin::run(pframes_t nframes)
 {
-       for (uint32_t i = 0; i < parameter_count(); ++i) {
+       uint32_t const N = parameter_count();
+       for (uint32_t i = 0; i < N; ++i) {
                if (parameter_is_control(i) && parameter_is_input(i)) {
                        _control_data[i] = _shadow_data[i];
                }
        }
 
        lilv_instance_run(_impl->instance, nframes);
+
+       if (_impl->work_iface) {
+               _worker->emit_responses();
+               if (_impl->work_iface->end_run) {
+                       _impl->work_iface->end_run(_impl->instance->lv2_handle);
+               }
+       }
 }
 
 void
@@ -1172,37 +1887,118 @@ LV2Plugin::latency_compute_run()
        deactivate();
 }
 
+const LilvPort*
+LV2Plugin::Impl::designated_input (const char* uri, void** bufptrs[], void** bufptr)
+{
+       const LilvPort* port = NULL;
+       LilvNode* designation = lilv_new_uri(_world.world, uri);
+       port = lilv_plugin_get_port_by_designation(
+               plugin, _world.lv2_InputPort, designation);
+       lilv_node_free(designation);
+       if (port) {
+               bufptrs[lilv_port_get_index(plugin, port)] = bufptr;
+       }
+       return port;
+}
+
+static bool lv2_filter (const string& str, void *arg)
+{
+       /* Not a dotfile, has a prefix before a period, suffix is "lv2" */
+       
+       return str[0] != '.' && (str.length() > 3 && str.find (".lv2") == (str.length() - 4));
+}
+
+
 LV2World::LV2World()
        : world(lilv_world_new())
+       , _bundle_checked(false)
 {
        lilv_world_load_all(world);
-       input_class     = lilv_new_uri(world, LILV_URI_INPUT_PORT);
-       output_class    = lilv_new_uri(world, LILV_URI_OUTPUT_PORT);
-       control_class   = lilv_new_uri(world, LILV_URI_CONTROL_PORT);
-       audio_class     = lilv_new_uri(world, LILV_URI_AUDIO_PORT);
-       event_class     = lilv_new_uri(world, LILV_URI_EVENT_PORT);
-       midi_class      = lilv_new_uri(world, LILV_URI_MIDI_EVENT);
-       in_place_broken = lilv_new_uri(world, LILV_NS_LV2 "inPlaceBroken");
-       integer         = lilv_new_uri(world, LILV_NS_LV2 "integer");
-       toggled         = lilv_new_uri(world, LILV_NS_LV2 "toggled");
-       srate           = lilv_new_uri(world, LILV_NS_LV2 "sampleRate");
-       gtk_gui         = lilv_new_uri(world, NS_UI "GtkUI");
-       external_gui    = lilv_new_uri(world, NS_UI "external");
-       logarithmic     = lilv_new_uri(world, "http://lv2plug.in/ns/dev/extportinfo#logarithmic");
+
+       atom_AtomPort      = lilv_new_uri(world, LV2_ATOM__AtomPort);
+       atom_Chunk         = lilv_new_uri(world, LV2_ATOM__Chunk);
+       atom_Sequence      = lilv_new_uri(world, LV2_ATOM__Sequence);
+       atom_bufferType    = lilv_new_uri(world, LV2_ATOM__bufferType);
+       atom_supports      = lilv_new_uri(world, LV2_ATOM__supports);
+       atom_eventTransfer = lilv_new_uri(world, LV2_ATOM__eventTransfer);
+       ev_EventPort       = lilv_new_uri(world, LILV_URI_EVENT_PORT);
+       ext_logarithmic    = lilv_new_uri(world, LV2_PORT_PROPS__logarithmic);
+       ext_notOnGUI       = lilv_new_uri(world, LV2_PORT_PROPS__notOnGUI);
+       lv2_AudioPort      = lilv_new_uri(world, LILV_URI_AUDIO_PORT);
+       lv2_ControlPort    = lilv_new_uri(world, LILV_URI_CONTROL_PORT);
+       lv2_InputPort      = lilv_new_uri(world, LILV_URI_INPUT_PORT);
+       lv2_OutputPort     = lilv_new_uri(world, LILV_URI_OUTPUT_PORT);
+       lv2_inPlaceBroken  = lilv_new_uri(world, LV2_CORE__inPlaceBroken);
+       lv2_integer        = lilv_new_uri(world, LV2_CORE__integer);
+       lv2_reportsLatency = lilv_new_uri(world, LV2_CORE__reportsLatency);
+       lv2_sampleRate     = lilv_new_uri(world, LV2_CORE__sampleRate);
+       lv2_toggled        = lilv_new_uri(world, LV2_CORE__toggled);
+       lv2_enumeration    = lilv_new_uri(world, LV2_CORE__enumeration);
+       lv2_freewheeling   = lilv_new_uri(world, LV2_CORE__freeWheeling);
+       midi_MidiEvent     = lilv_new_uri(world, LILV_URI_MIDI_EVENT);
+       rdfs_comment       = lilv_new_uri(world, LILV_NS_RDFS "comment");
+       rsz_minimumSize    = lilv_new_uri(world, LV2_RESIZE_PORT__minimumSize);
+       time_Position      = lilv_new_uri(world, LV2_TIME__Position);
+       ui_GtkUI           = lilv_new_uri(world, LV2_UI__GtkUI);
+       ui_external        = lilv_new_uri(world, "http://lv2plug.in/ns/extensions/ui#external");
 }
 
 LV2World::~LV2World()
 {
-       lilv_node_free(input_class);
-       lilv_node_free(output_class);
-       lilv_node_free(control_class);
-       lilv_node_free(audio_class);
-       lilv_node_free(event_class);
-       lilv_node_free(midi_class);
-       lilv_node_free(in_place_broken);
+       lilv_node_free(ui_external);
+       lilv_node_free(ui_GtkUI);
+       lilv_node_free(time_Position);
+       lilv_node_free(rsz_minimumSize);
+       lilv_node_free(rdfs_comment);
+       lilv_node_free(midi_MidiEvent);
+       lilv_node_free(lv2_enumeration);
+       lilv_node_free(lv2_freewheeling);
+       lilv_node_free(lv2_toggled);
+       lilv_node_free(lv2_sampleRate);
+       lilv_node_free(lv2_reportsLatency);
+       lilv_node_free(lv2_integer);
+       lilv_node_free(lv2_inPlaceBroken);
+       lilv_node_free(lv2_OutputPort);
+       lilv_node_free(lv2_InputPort);
+       lilv_node_free(lv2_ControlPort);
+       lilv_node_free(lv2_AudioPort);
+       lilv_node_free(ext_notOnGUI);
+       lilv_node_free(ext_logarithmic);
+       lilv_node_free(ev_EventPort);
+       lilv_node_free(atom_supports);
+       lilv_node_free(atom_eventTransfer);
+       lilv_node_free(atom_bufferType);
+       lilv_node_free(atom_Sequence);
+       lilv_node_free(atom_Chunk);
+       lilv_node_free(atom_AtomPort);
+}
+
+void
+LV2World::load_bundled_plugins()
+{
+       if (!_bundle_checked) {
+               cout << "Scanning folders for bundled LV2s: " << ARDOUR::lv2_bundled_search_path().to_string() << endl;
+               PathScanner scanner;
+               vector<string *> *plugin_objects = scanner (ARDOUR::lv2_bundled_search_path().to_string(), lv2_filter, 0, true, true);
+               if (plugin_objects) {
+                       for ( vector<string *>::iterator x = plugin_objects->begin(); x != plugin_objects->end (); ++x) {
+#ifdef WINDOWS
+                               string uri = "file:///" + **x + "/";
+#else
+                               string uri = "file://" + **x + "/";
+#endif
+                               LilvNode *node = lilv_new_uri(world, uri.c_str());
+                               lilv_world_load_bundle(world, node);
+                               lilv_node_free(node);
+                       }
+               }
+               delete (plugin_objects);
+
+               _bundle_checked = true;
+       }
 }
 
-LV2PluginInfo::LV2PluginInfo (void* c_plugin)
+LV2PluginInfo::LV2PluginInfo (const void* c_plugin)
        : _c_plugin(c_plugin)
 {
        type = ARDOUR::LV2;
@@ -1218,7 +2014,7 @@ LV2PluginInfo::load(Session& session)
                PluginPtr plugin;
 
                plugin.reset(new LV2Plugin(session.engine(), session,
-                                          (LilvPlugin*)_c_plugin,
+                                          (const LilvPlugin*)_c_plugin,
                                           session.frame_rate()));
 
                plugin->set_info(PluginInfoPtr(new LV2PluginInfo(*this)));
@@ -1233,18 +2029,22 @@ LV2PluginInfo::load(Session& session)
 PluginInfoList*
 LV2PluginInfo::discover()
 {
+       _world.load_bundled_plugins();
+
        PluginInfoList*    plugs   = new PluginInfoList;
        const LilvPlugins* plugins = lilv_world_get_all_plugins(_world.world);
 
-       cerr << "LV2: Discovering " << lilv_plugins_size(plugins) << " plugins" << endl;
+       info << "LV2: Discovering " << lilv_plugins_size(plugins) << " plugins" << endmsg;
 
        LILV_FOREACH(plugins, i, plugins) {
                const LilvPlugin* p = lilv_plugins_get(plugins, i);
-               LV2PluginInfoPtr  info(new LV2PluginInfo((void*)p));
+               LV2PluginInfoPtr  info(new LV2PluginInfo((const void*)p));
 
                LilvNode* name = lilv_plugin_get_name(p);
-               if (!name) {
-                       cerr << "LV2: invalid plugin\n";
+               if (!name || !lilv_plugin_get_port_by_index(p, 0)) {
+                       warning << "Ignoring invalid LV2 plugin "
+                               << lilv_node_as_string(lilv_plugin_get_uri(p))
+                               << endmsg;
                        continue;
                }
 
@@ -1263,19 +2063,50 @@ LV2PluginInfo::discover()
 
                info->path = "/NOPATH"; // Meaningless for LV2
 
+               /* count atom-event-ports that feature
+                * atom:supports <http://lv2plug.in/ns/ext/midi#MidiEvent>
+                *
+                * TODO: nicely ask drobilla to make a lilv_ call for that
+                */
+               int count_midi_out = 0;
+               int count_midi_in = 0;
+               for (uint32_t i = 0; i < lilv_plugin_get_num_ports(p); ++i) {
+                       const LilvPort* port  = lilv_plugin_get_port_by_index(p, i);
+                       if (lilv_port_is_a(p, port, _world.atom_AtomPort)) {
+                               LilvNodes* buffer_types = lilv_port_get_value(
+                                       p, port, _world.atom_bufferType);
+                               LilvNodes* atom_supports = lilv_port_get_value(
+                                       p, port, _world.atom_supports);
+
+                               if (lilv_nodes_contains(buffer_types, _world.atom_Sequence)
+                                               && lilv_nodes_contains(atom_supports, _world.midi_MidiEvent)) {
+                                       if (lilv_port_is_a(p, port, _world.lv2_InputPort)) {
+                                               count_midi_in++;
+                                       }
+                                       if (lilv_port_is_a(p, port, _world.lv2_OutputPort)) {
+                                               count_midi_out++;
+                                       }
+                               }
+                               lilv_nodes_free(buffer_types);
+                               lilv_nodes_free(atom_supports);
+                       }
+               }
+
                info->n_inputs.set_audio(
                        lilv_plugin_get_num_ports_of_class(
-                               p, _world.input_class, _world.audio_class, NULL));
+                               p, _world.lv2_InputPort, _world.lv2_AudioPort, NULL));
                info->n_inputs.set_midi(
                        lilv_plugin_get_num_ports_of_class(
-                               p, _world.input_class, _world.event_class, NULL));
+                               p, _world.lv2_InputPort, _world.ev_EventPort, NULL)
+                       + count_midi_in);
 
                info->n_outputs.set_audio(
                        lilv_plugin_get_num_ports_of_class(
-                               p, _world.output_class, _world.audio_class, NULL));
+                               p, _world.lv2_OutputPort, _world.lv2_AudioPort, NULL));
                info->n_outputs.set_midi(
                        lilv_plugin_get_num_ports_of_class(
-                               p, _world.output_class, _world.event_class, NULL));
+                               p, _world.lv2_OutputPort, _world.ev_EventPort, NULL)
+                       + count_midi_out);
 
                info->unique_id = lilv_node_as_uri(lilv_plugin_get_uri(p));
                info->index     = 0; // Meaningless for LV2
@@ -1283,7 +2114,5 @@ LV2PluginInfo::discover()
                plugs->push_back(info);
        }
 
-       cerr << "Done LV2 discovery" << endl;
-
        return plugs;
 }