Added multi-bus support for audio plug-in clients

examples/PlugInSamples/GainPlugIn/Source/GainProcessor.cpp

@@ -0,0 +1,96 @@
+/*
+ ==============================================================================
+
+ GainProcessor.cpp
+ Created: 23 Nov 2015 3:08:33pm
+ Author:  Fabian Renn
+
+ ==============================================================================
+ */
+
+#include "../JuceLibraryCode/JuceHeader.h"
+#include "../../GenericEditor.h"
+
+//==============================================================================
+/**
+ */
+class GainProcessor  : public AudioProcessor
+{
+public:
+
+    //==============================================================================
+    GainProcessor()
+    {
+        addParameter (gain = new AudioParameterFloat ("gain", "Gain", 0.0f, 1.0f, 0.5f));
+    }
+
+    ~GainProcessor() {}
+
+    //==============================================================================
+    void prepareToPlay (double sampleRate, int samplesPerBlock) override {}
+    void releaseResources() override {}
+
+    void processBlock (AudioSampleBuffer& buffer, MidiBuffer&) override
+    {
+        buffer.applyGain (*gain);
+    }
+
+    //==============================================================================
+    AudioProcessorEditor* createEditor() override { return new GenericEditor (*this); }
+    bool hasEditor() const override               { return true;   }
+
+    //==============================================================================
+    const String getName() const override               { return "Gain PlugIn"; }
+    bool acceptsMidi() const override                   { return false; }
+    bool producesMidi() const override                  { return false; }
+    bool silenceInProducesSilenceOut() const override   { return true; }
+    double getTailLengthSeconds() const override        { return 0; }
+
+    //==============================================================================
+    int getNumPrograms() override                          { return 1; }
+    int getCurrentProgram() override                       { return 0; }
+    void setCurrentProgram (int) override                  {}
+    const String getProgramName (int) override             { return String(); }
+    void changeProgramName (int , const String& ) override { }
+
+    //==============================================================================
+    void getStateInformation (MemoryBlock& destData) override
+    {
+        MemoryOutputStream (destData, true).writeFloat (*gain);
+    }
+
+    void setStateInformation (const void* data, int sizeInBytes) override
+    {
+        gain->setValueNotifyingHost (MemoryInputStream (data, sizeInBytes, false).readFloat());
+    }
+
+    //==============================================================================
+    bool setPreferredBusArrangement (bool isInputBus, int busIndex,
+                                     const AudioChannelSet& preferred) override
+    {
+        const int numChannels = preferred.size();
+
+        // do not allow disabling channels
+        if (numChannels == 0) return false;
+
+        // always have the same channel layout on both input and output on the main bus
+        if (! AudioProcessor::setPreferredBusArrangement (! isInputBus, busIndex, preferred))
+            return false;
+
+        return AudioProcessor::setPreferredBusArrangement (isInputBus, busIndex, preferred);
+    }
+
+private:
+    //==============================================================================
+    AudioParameterFloat* gain;
+
+    //==============================================================================
+    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (GainProcessor)
+};
+
+//==============================================================================
+// This creates new instances of the plugin..
+AudioProcessor* JUCE_CALLTYPE createPluginFilter()
+{
+    return new GainProcessor();
+}