/*
* Copyright (C) 2010 Google Inc. All rights reserved.
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* modification, are permitted provided that the following conditions
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*
* 1. Redistributions of source code must retain the above copyright
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* its contributors may be used to endorse or promote products derived
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*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
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#ifndef ReverbAccumulationBuffer_h
#define ReverbAccumulationBuffer_h
#include "platform/PlatformExport.h"
#include "platform/audio/AudioArray.h"
namespace WebCore {
// ReverbAccumulationBuffer is a circular delay buffer with one client reading from it and multiple clients
// writing/accumulating to it at different delay offsets from the read position. The read operation will zero the memory
// just read from the buffer, so it will be ready for accumulation the next time around.
class PLATFORM_EXPORT ReverbAccumulationBuffer {
public:
ReverbAccumulationBuffer(size_t length);
// This will read from, then clear-out numberOfFrames
void readAndClear(float* destination, size_t numberOfFrames);
// Each ReverbConvolverStage will accumulate its output at the appropriate delay from the read position.
// We need to pass in and update readIndex here, since each ReverbConvolverStage may be running in
// a different thread than the realtime thread calling ReadAndClear() and maintaining m_readIndex
// Returns the writeIndex where the accumulation took place
int accumulate(float* source, size_t numberOfFrames, int* readIndex, size_t delayFrames);
size_t readIndex() const { return m_readIndex; }
void updateReadIndex(int* readIndex, size_t numberOfFrames) const;
size_t readTimeFrame() const { return m_readTimeFrame; }
void reset();
private:
AudioFloatArray m_buffer;
size_t m_readIndex;
size_t m_readTimeFrame; // for debugging (frame on continuous timeline)
};
} // namespace WebCore
#endif // ReverbAccumulationBuffer_h