Add AudioPort struct and hints; Implement CV and Sidechain in LV2

distrho/DistrhoPlugin.hpp

@@ -185,6 +185,29 @@ START_NAMESPACE_DISTRHO
 
 #endif
 
+/* ------------------------------------------------------------------------------------------------------------
+ * Audio Port Hints */
+
+/**
+   @defgroup AudioPortHints Audio Port Hints
+
+   Various audio port hints.
+   @see AudioPort::hints
+   @{
+ */
+
+/**
+   Audio port can be used as control voltage (LV2 only).
+ */
+static const uint32_t kAudioPortIsCV = 0x1;
+
+/**
+   Audio port should be used as sidechan (LV2 only).
+ */
+static const uint32_t kAudioPortIsSidechain = 0x2;
+
+/** @} */
+
 /* ------------------------------------------------------------------------------------------------------------
  * Parameter Hints */
 
@@ -243,6 +266,40 @@ static const uint32_t kParameterIsCV = 0x20;
    @{
  */
 
+/**
+   Audio Port.
+ */
+struct AudioPort {
+   /**
+      Hints describing this audio port.
+      @see AudioPortHints
+    */
+    uint32_t hints;
+
+   /**
+      The name of this audio port.
+      An audio port name can contain any character, but hosts might have a hard time with non-ascii ones.
+      The name doesn't have to be unique within a plugin instance, but it's recommended.
+    */
+    d_string name;
+
+   /**
+      The symbol of this audio port.
+      An audio port symbol is a short restricted name used as a machine and human readable identifier.
+      The first character must be one of _, a-z or A-Z and subsequent characters can be from _, a-z, A-Z and 0-9.
+      @note: Audio port and parameter symbols MUST be unique within a plugin instance.
+    */
+    d_string symbol;
+
+   /**
+      Default constructor for a regular audio port.
+    */
+    AudioPort() noexcept
+        : hints(0x0),
+          name(),
+          symbol() {}
+};
+
 /**
    Parameter ranges.
    This is used to set the default, minimum and maximum values of a parameter.
@@ -670,6 +727,12 @@ protected:
    /* --------------------------------------------------------------------------------------------------------
     * Init */
 
+   /**
+      Initialize the audio port @a index.
+      This function will be called once, shortly after the plugin is created.
+    */
+    virtual void d_initAudioPort(bool input, uint32_t index, AudioPort& port);
+
    /**
       Initialize the parameter @a index.
       This function will be called once, shortly after the plugin is created.

distrho/src/DistrhoPlugin.cpp

@@ -28,6 +28,7 @@ double   d_lastSampleRate = 0.0;
  * Static fallback data, see DistrhoPluginInternal.hpp */
 
 const d_string        PluginExporter::sFallbackString;
+const AudioPort       PluginExporter::sFallbackAudioPort;
 const ParameterRanges PluginExporter::sFallbackRanges;
 
 /* ------------------------------------------------------------------------------------------------------------
@@ -36,6 +37,10 @@ const ParameterRanges PluginExporter::sFallbackRanges;
 Plugin::Plugin(const uint32_t parameterCount, const uint32_t programCount, const uint32_t stateCount)
     : pData(new PrivateData())
 {
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+    pData->audioPorts = new AudioPort[DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS];
+#endif
+
     if (parameterCount > 0)
     {
         pData->parameterCount = parameterCount;
@@ -104,6 +109,27 @@ bool Plugin::d_writeMidiEvent(const MidiEvent& /*midiEvent*/) noexcept
 }
 #endif
 
+/* ------------------------------------------------------------------------------------------------------------
+ * Init */
+
+void Plugin::d_initAudioPort(bool input, uint32_t index, AudioPort& port)
+{
+    if (port.hints & kAudioPortIsCV)
+    {
+        port.name    = input ? "CV Input " : "CV Output ";
+        port.name   += d_string(index+1);
+        port.symbol  = input ? "cv_in_" : "cv_out_";
+        port.symbol += d_string(index+1);
+    }
+    else
+    {
+        port.name    = input ? "Audio Input " : "Audio Output ";
+        port.name   += d_string(index+1);
+        port.symbol  = input ? "audio_in_" : "audio_out_";
+        port.symbol += d_string(index+1);
+    }
+}
+
 /* ------------------------------------------------------------------------------------------------------------
  * Callbacks (optional) */
 

distrho/src/DistrhoPluginInternal.hpp

@@ -38,6 +38,10 @@ extern double   d_lastSampleRate;
 struct Plugin::PrivateData {
     bool isProcessing;
 
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+    AudioPort* audioPorts;
+#endif
+
     uint32_t   parameterCount;
     Parameter* parameters;
 
@@ -65,6 +69,9 @@ struct Plugin::PrivateData {
 
     PrivateData() noexcept
         : isProcessing(false),
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+          audioPorts(nullptr),
+#endif
           parameterCount(0),
           parameters(nullptr),
 #if DISTRHO_PLUGIN_WANT_PROGRAMS
@@ -88,6 +95,14 @@ struct Plugin::PrivateData {
 
     ~PrivateData() noexcept
     {
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+        if (audioPorts != nullptr)
+        {
+            delete[] audioPorts;
+            audioPorts = nullptr;
+        }
+#endif
+
         if (parameters != nullptr)
         {
             delete[] parameters;
@@ -132,6 +147,16 @@ public:
         DISTRHO_SAFE_ASSERT_RETURN(fPlugin != nullptr,);
         DISTRHO_SAFE_ASSERT_RETURN(fData != nullptr,);
 
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+        {
+            uint32_t j=0;
+            for (uint32_t i=0; i < DISTRHO_PLUGIN_NUM_INPUTS; ++i, ++j)
+                fPlugin->d_initAudioPort(true, i, fData->audioPorts[j]);
+            for (uint32_t i=0; i < DISTRHO_PLUGIN_NUM_OUTPUTS; ++i, ++j)
+                fPlugin->d_initAudioPort(false, i, fData->audioPorts[j]);
+        }
+#endif
+
         for (uint32_t i=0, count=fData->parameterCount; i < count; ++i)
             fPlugin->d_initParameter(i, fData->parameters[i]);
 
@@ -211,6 +236,21 @@ public:
     }
 #endif
 
+#if DISTRHO_PLUGIN_NUM_INPUTS+DISTRHO_PLUGIN_NUM_OUTPUTS > 0
+    const AudioPort& getAudioPort(const bool input, const uint32_t index) const noexcept
+    {
+        DISTRHO_SAFE_ASSERT_RETURN(fData != nullptr, sFallbackAudioPort);
+
+        if (input) {
+            DISTRHO_SAFE_ASSERT_RETURN(index < DISTRHO_PLUGIN_NUM_INPUTS,  sFallbackAudioPort);
+        } else {
+            DISTRHO_SAFE_ASSERT_RETURN(index < DISTRHO_PLUGIN_NUM_OUTPUTS, sFallbackAudioPort);
+        }
+
+        return fData->audioPorts[index + (input ? 0 : DISTRHO_PLUGIN_NUM_INPUTS)];
+    }
+#endif
+
     uint32_t getParameterCount() const noexcept
     {
         DISTRHO_SAFE_ASSERT_RETURN(fData != nullptr, 0);
@@ -458,6 +498,7 @@ private:
     // Static fallback data, see DistrhoPlugin.cpp
 
     static const d_string        sFallbackString;
+    static const AudioPort       sFallbackAudioPort;
     static const ParameterRanges sFallbackRanges;
 
     DISTRHO_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR(PluginExporter)

distrho/src/DistrhoPluginLV2export.cpp

@@ -109,6 +109,7 @@ void lv2_generate_ttl(const char* const basename)
 # else
         manifestString += "    ui:binary <" + pluginDLL + "." DISTRHO_DLL_EXTENSION "> ;\n";
 #endif
+        manifestString += "\n";
         manifestString += "    lv2:extensionData ui:idleInterface ,\n";
 # if DISTRHO_PLUGIN_WANT_PROGRAMS
         manifestString += "                      ui:showInterface ,\n";
@@ -116,9 +117,11 @@ void lv2_generate_ttl(const char* const basename)
 # else
         manifestString += "                      ui:showInterface ;\n";
 # endif
+        manifestString += "\n";
         manifestString += "    lv2:optionalFeature ui:noUserResize ,\n";
         manifestString += "                        ui:resize ,\n";
         manifestString += "                        ui:touch ;\n";
+        manifestString += "\n";
 # if DISTRHO_PLUGIN_WANT_DIRECT_ACCESS
         manifestString += "    lv2:requiredFeature <" LV2_DATA_ACCESS_URI "> ,\n";
         manifestString += "                        <" LV2_INSTANCE_ACCESS_URI "> ,\n";
@@ -205,18 +208,27 @@ void lv2_generate_ttl(const char* const basename)
 #if DISTRHO_PLUGIN_NUM_INPUTS > 0
             for (uint32_t i=0; i < DISTRHO_PLUGIN_NUM_INPUTS; ++i, ++portIndex)
             {
+                const AudioPort& port(plugin.getAudioPort(true, i));
+
                 if (i == 0)
                     pluginString += "    lv2:port [\n";
                 else
                     pluginString += "    [\n";
 
-                pluginString += "        a lv2:InputPort, lv2:AudioPort ;\n";
+                if (port.hints & kAudioPortIsCV)
+                    pluginString += "        a lv2:InputPort, lv2:CVPort ;\n";
+                else
+                    pluginString += "        a lv2:InputPort, lv2:AudioPort ;\n";
+
                 pluginString += "        lv2:index " + d_string(portIndex) + " ;\n";
-                pluginString += "        lv2:symbol \"lv2_audio_in_" + d_string(i+1) + "\" ;\n";
-                pluginString += "        lv2:name \"Audio Input " + d_string(i+1) + "\" ;\n";
+                pluginString += "        lv2:symbol \"" + port.symbol + "\" ;\n";
+                pluginString += "        lv2:name \"" + port.name + "\" ;\n";
+
+                if (port.hints & kAudioPortIsSidechain)
+                    pluginString += "        lv2:portProperty lv2:isSideChain;\n";
 
                 if (i+1 == DISTRHO_PLUGIN_NUM_INPUTS)
-                    pluginString += "    ] ;\n\n";
+                    pluginString += "    ] ;\n";
                 else
                     pluginString += "    ] ,\n";
             }
@@ -226,18 +238,27 @@ void lv2_generate_ttl(const char* const basename)
 #if DISTRHO_PLUGIN_NUM_OUTPUTS > 0
             for (uint32_t i=0; i < DISTRHO_PLUGIN_NUM_OUTPUTS; ++i, ++portIndex)
             {
+                const AudioPort& port(plugin.getAudioPort(false, i));
+
                 if (i == 0)
                     pluginString += "    lv2:port [\n";
                 else
                     pluginString += "    [\n";
 
-                pluginString += "        a lv2:OutputPort, lv2:AudioPort ;\n";
+                if (port.hints & kAudioPortIsCV)
+                    pluginString += "        a lv2:OutputPort, lv2:CVPort ;\n";
+                else
+                    pluginString += "        a lv2:OutputPort, lv2:AudioPort ;\n";
+
                 pluginString += "        lv2:index " + d_string(portIndex) + " ;\n";
-                pluginString += "        lv2:symbol \"lv2_audio_out_" + d_string(i+1) + "\" ;\n";
-                pluginString += "        lv2:name \"Audio Output " + d_string(i+1) + "\" ;\n";
+                pluginString += "        lv2:symbol \"" + port.symbol + "\" ;\n";
+                pluginString += "        lv2:name \"" + port.name + "\" ;\n";
+
+                if (port.hints & kAudioPortIsSidechain)
+                    pluginString += "        lv2:portProperty lv2:isSideChain;\n";
 
                 if (i+1 == DISTRHO_PLUGIN_NUM_OUTPUTS)
-                    pluginString += "    ] ;\n\n";
+                    pluginString += "    ] ;\n";
                 else
                     pluginString += "    ] ,\n";
             }