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 /*

  * Copyright (C) 2010 Google Inc. All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  * 1.  Redistributions of source code must retain the above copyright

  *     notice, this list of conditions and the following disclaimer.

  * 2.  Redistributions in binary form must reproduce the above copyright

  *     notice, this list of conditions and the following disclaimer in the

  *     documentation and/or other materials provided with the distribution.

  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of

  *     its contributors may be used to endorse or promote products derived

  *     from this software without specific prior written permission.

  *

  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY

  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED

  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE

  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY

  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;

  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF

  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 #ifndef ReverbAccumulationBuffer_h

 #define ReverbAccumulationBuffer_h

 #include "nsTArray.h"

 #include "mozilla/MemoryReporting.h"

 namespace WebCore {

 typedef nsTArray<float> AudioFloatArray;

 // 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 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();

     size_t sizeOfExcludingThis(mozilla::MallocSizeOf aMallocSizeOf) const

     {

         return m_buffer.SizeOfExcludingThis(aMallocSizeOf);

     }

 private:

     AudioFloatArray m_buffer;

     size_t m_readIndex;

     size_t m_readTimeFrame; // for debugging (frame on continuous timeline)

 };

 } // namespace WebCore

 #endif // ReverbAccumulationBuffer_h