Fix local injector modifying system volume

libraries/audio-client/src/AudioClient.cpp

@@ -981,7 +981,7 @@ void AudioClient::selectAudioSourceSine440() {
     _noiseSourceEnabled = false;
 }
 
-bool AudioClient::outputLocalInjector(bool isStereo, qreal volume, AudioInjector* injector) {
+bool AudioClient::outputLocalInjector(bool isStereo, AudioInjector* injector) {
     if (injector->getLocalBuffer()) {
         QAudioFormat localFormat = _desiredOutputFormat;
         localFormat.setChannelCount(isStereo ? 2 : 1);
@@ -990,8 +990,6 @@ bool AudioClient::outputLocalInjector(bool isStereo, qreal volume, AudioInjector
                                                      localFormat,
                                                      injector->getLocalBuffer());
         
-        localOutput->setVolume(volume);
-        
         // move the localOutput to the same thread as the local injector buffer
         localOutput->moveToThread(injector->getLocalBuffer()->thread());
         

libraries/audio-client/src/AudioClient.h

@@ -157,7 +157,7 @@ public slots:
 
     void setOutputBufferSize(int numFrames);
 
-    virtual bool outputLocalInjector(bool isStereo, qreal volume, AudioInjector* injector);
+    virtual bool outputLocalInjector(bool isStereo, AudioInjector* injector);
 
     bool switchInputToAudioDevice(const QString& inputDeviceName);
     bool switchOutputToAudioDevice(const QString& outputDeviceName);

libraries/audio/src/AbstractAudioInterface.h

@@ -26,7 +26,7 @@ public:
     AbstractAudioInterface(QObject* parent = 0) : QObject(parent) {};
     
 public slots:
-    virtual bool outputLocalInjector(bool isStereo, qreal volume, AudioInjector* injector) = 0;
+    virtual bool outputLocalInjector(bool isStereo, AudioInjector* injector) = 0;
     
     virtual void enableAudioSourceInject(bool enable) = 0;
     virtual void selectAudioSourcePinkNoise() = 0;

libraries/audio/src/AudioInjector.cpp

@@ -105,11 +105,12 @@ void AudioInjector::injectLocally() {
             
             _localBuffer->open(QIODevice::ReadOnly);
             _localBuffer->setShouldLoop(_options.loop);
+            _localBuffer->setVolume(_options.volume);
             
             // give our current send position to the local buffer
             _localBuffer->setCurrentOffset(_currentSendPosition);
             
-            success = _localAudioInterface->outputLocalInjector(_options.stereo, _options.volume, this);
+            success = _localAudioInterface->outputLocalInjector(_options.stereo, this);
             
             // if we're not looping and the buffer tells us it is empty then emit finished
             connect(_localBuffer, &AudioInjectorLocalBuffer::bufferEmpty, this, &AudioInjector::stop);

libraries/audio/src/AudioInjectorLocalBuffer.cpp

@@ -16,7 +16,8 @@ AudioInjectorLocalBuffer::AudioInjectorLocalBuffer(const QByteArray& rawAudioArr
     _rawAudioArray(rawAudioArray),
     _shouldLoop(false),
     _isStopped(false),
-    _currentOffset(0)
+    _currentOffset(0),
+    _volume(1.0f)
 {
     
 }
@@ -35,6 +36,18 @@ bool AudioInjectorLocalBuffer::seek(qint64 pos) {
     }
 }
 
+void copy(char* to, char* from, int size, qreal factor) {
+    int16_t* toArray = (int16_t*) to;
+    int16_t* fromArray = (int16_t*) from;
+    int sampleSize = size / sizeof(int16_t);
+    
+    for (int i = 0; i < sampleSize; i++) {
+        *toArray = factor * (*fromArray);
+        toArray++;
+        fromArray++;
+    }
+}
+
 qint64 AudioInjectorLocalBuffer::readData(char* data, qint64 maxSize) {
     if (!_isStopped) {
         
@@ -47,7 +60,7 @@ qint64 AudioInjectorLocalBuffer::readData(char* data, qint64 maxSize) {
             bytesRead = bytesToEnd;
         }
         
-        memcpy(data, _rawAudioArray.data() + _currentOffset, bytesRead);
+        copy(data, _rawAudioArray.data() + _currentOffset, bytesRead, _volume);
         
         // now check if we are supposed to loop and if we can copy more from the beginning
         if (_shouldLoop && maxSize != bytesRead) {
@@ -78,7 +91,7 @@ qint64 AudioInjectorLocalBuffer::recursiveReadFromFront(char* data, qint64 maxSi
     }
     
     // copy that amount
-    memcpy(data, _rawAudioArray.data(), bytesRead);
+    copy(data, _rawAudioArray.data(), bytesRead, _volume);
     
     // check if we need to call ourselves again and pull from the front again
     if (bytesRead < maxSize) {

libraries/audio/src/AudioInjectorLocalBuffer.h

@@ -14,6 +14,8 @@
 
 #include <QtCore/qiodevice.h>
 
+#include <glm/detail/func_common.hpp>
+
 class AudioInjectorLocalBuffer : public QIODevice {
     Q_OBJECT
 public:
@@ -27,12 +29,13 @@ public:
     qint64 writeData(const char* data, qint64 maxSize) { return 0; }
     
     void setShouldLoop(bool shouldLoop) { _shouldLoop = shouldLoop; }
-    
     void setCurrentOffset(int currentOffset) { _currentOffset = currentOffset; }
+    void setVolume(float volume) { _volume = glm::clamp(volume, 0.0f, 1.0f); }
+    
 signals:
     void bufferEmpty();
-private:
     
+private:
     qint64 recursiveReadFromFront(char* data, qint64 maxSize);
     
     QByteArray _rawAudioArray;
@@ -40,6 +43,7 @@ private:
     bool _isStopped;
     
     int _currentOffset;
+    float _volume;
 };
 
 #endif // hifi_AudioInjectorLocalBuffer_h