Set tooltips on generic UI controls for LV2 plugin controls with documentation (rdfs:comment property).

git-svn-id: svn://localhost/ardour2/branches/3.0@12042 d708f5d6-7413-0410-9779-e7cbd77b26cf

4 files changed, 34 insertions, 8 deletions

diff --git a/gtk2_ardour/generic_pluginui.cc b/gtk2_ardour/generic_pluginui.cc
index 3f8d0f63c9..6306c051e5 100644
--- a/gtk2_ardour/generic_pluginui.cc
+++ b/gtk2_ardour/generic_pluginui.cc
@@ -264,6 +264,11 @@ GenericPluginUI::build ()
 				continue;
 			}
 
+			const std::string param_docs = plugin->get_parameter_docs(i);
+			if (param_docs != "") {
+				ARDOUR_UI::instance()->set_tip(cui, param_docs.c_str());
+			}
+
 			if (cui->controller || cui->clickbox || cui->combo) {
 				// Get all of the controls into a list, so that
 				// we can lay them out a bit more nicely later.
diff --git a/libs/ardour/ardour/lv2_plugin.h b/libs/ardour/ardour/lv2_plugin.h
index 51d88a672d..b72b7d605b 100644
--- a/libs/ardour/ardour/lv2_plugin.h
+++ b/libs/ardour/ardour/lv2_plugin.h
@@ -50,14 +50,15 @@ class LV2Plugin : public ARDOUR::Plugin, public ARDOUR::Workee
 	const char* name () const;
 	const char* maker () const;
 
-	uint32_t   num_ports () const;
-	uint32_t   parameter_count () const;
-	float      default_value (uint32_t port);
-	framecnt_t signal_latency () const;
-	void       set_parameter (uint32_t port, float val);
-	float      get_parameter (uint32_t port) const;
-	int        get_parameter_descriptor (uint32_t which, ParameterDescriptor&) const;
-	uint32_t   nth_parameter (uint32_t port, bool& ok) const;
+	uint32_t    num_ports () const;
+	uint32_t    parameter_count () const;
+	float       default_value (uint32_t port);
+	framecnt_t  signal_latency () const;
+	void        set_parameter (uint32_t port, float val);
+	float       get_parameter (uint32_t port) const;
+	std::string get_parameter_docs(uint32_t which) const;
+	int         get_parameter_descriptor (uint32_t which, ParameterDescriptor&) const;
+	uint32_t    nth_parameter (uint32_t port, bool& ok) const;
 
 	const void* extension_data (const char* uri) const;
 
diff --git a/libs/ardour/ardour/plugin.h b/libs/ardour/ardour/plugin.h
index d73fef2f53..bade84341b 100644
--- a/libs/ardour/ardour/plugin.h
+++ b/libs/ardour/ardour/plugin.h
@@ -118,6 +118,7 @@ class Plugin : public PBD::StatefulDestructible, public Latent
 	virtual uint32_t parameter_count () const = 0;
 	virtual float default_value (uint32_t port) = 0;
 	virtual float get_parameter(uint32_t which) const = 0;
+	virtual std::string get_parameter_docs(uint32_t which) const { return ""; }
 
 	virtual int get_parameter_descriptor (uint32_t which, ParameterDescriptor&) const = 0;
 	virtual uint32_t nth_parameter (uint32_t which, bool& ok) const = 0;
diff --git a/libs/ardour/lv2_plugin.cc b/libs/ardour/lv2_plugin.cc
index dc312a099b..bd628e46bd 100644
--- a/libs/ardour/lv2_plugin.cc
+++ b/libs/ardour/lv2_plugin.cc
@@ -108,6 +108,7 @@ public:
 	LilvNode* lv2_sampleRate;
 	LilvNode* lv2_toggled;
 	LilvNode* midi_MidiEvent;
+	LilvNode* rdfs_comment;
 	LilvNode* ui_GtkUI;
 	LilvNode* ui_external;
 };
@@ -583,6 +584,23 @@ LV2Plugin::get_parameter(uint32_t which) const
 	return 0.0f;
 }
 
+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
 {
@@ -1466,6 +1484,7 @@ LV2World::LV2World()
 	lv2_toggled        = lilv_new_uri(world, LILV_NS_LV2 "toggled");
 	lv2_enumeration    = lilv_new_uri(world, LILV_NS_LV2 "enumeration");
 	midi_MidiEvent     = lilv_new_uri(world, LILV_URI_MIDI_EVENT);
+	rdfs_comment       = lilv_new_uri(world, LILV_NS_RDFS "comment");
 	ui_GtkUI           = lilv_new_uri(world, NS_UI "GtkUI");
 	ui_external        = lilv_new_uri(world, NS_UI "external");
 }