new tone generator audio source object

libraries/audio/src/AudioSourceTone.cpp

@@ -0,0 +1,20 @@
+//
+//  AudioSourceTone.cpp
+//  hifi
+//
+//  Created by Craig Hansen-Sturm on 8/10/14.
+//  Copyright 2014 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#include <assert.h>
+#include <math.h>
+#include <SharedUtil.h>
+#include "AudioRingBuffer.h"
+#include "AudioFormat.h"
+#include "AudioBuffer.h"
+#include "AudioSourceTone.h"
+
+uint32_t AudioSourceTone::_frameOffset = 0;

libraries/audio/src/AudioSourceTone.h

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+//
+//  AudioSourceTone.h
+//  hifi
+//
+//  Created by Craig Hansen-Sturm on 9/1/14.
+//  Copyright 2014 High Fidelity, Inc.
+//
+//  Distributed under the Apache License, Version 2.0.
+//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
+//
+
+#ifndef hifi_AudioSourceTone_h
+#define hifi_AudioSourceTone_h
+
+class AudioSourceTone
+{
+    static uint32_t _frameOffset;
+    float32_t _frequency;
+    float32_t _sampleRate;
+    float32_t _omega;
+    
+public:
+    AudioSourceTone() {
+        initialize();
+    }
+    
+    ~AudioSourceTone() {
+        finalize();
+    }
+    
+    void initialize() {
+        _frameOffset = 0;
+        setParameters(SAMPLE_RATE, 220.0f);
+    }
+    
+    void finalize() {
+    }
+    
+    void reset() {
+        _frameOffset = 0;
+    }
+
+    void setParameters(const float32_t sampleRate, const float32_t frequency) {
+        _sampleRate = std::max(sampleRate, 1.0f);
+        _frequency = std::max(frequency, 1.0f);
+        _omega = _frequency / _sampleRate * TWO_PI;
+    }
+    
+    void getParameters(float32_t& sampleRate, float32_t& frequency) {
+        sampleRate = _sampleRate;
+        frequency = _frequency;
+    }
+
+    void render(AudioBufferFloat32& frameBuffer) {
+        
+        // note: this is a placeholder implementation. final version will not include any transcendental ops in our render loop
+        
+        float32_t** samples = frameBuffer.getFrameData();
+        for (uint16_t i = 0; i < frameBuffer.getFrameCount(); ++i) {
+            for (uint16_t j = 0; j < frameBuffer.getChannelCount(); ++j) {
+                samples[j][i] = sinf((i + _frameOffset) * _omega);
+            }
+        }
+        _frameOffset += frameBuffer.getFrameCount();
+    }
+};
+
+#endif 
+