services/oboeservice/AAudioMixer.h

/*
 * Copyright (C) 2017 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef AAUDIO_AAUDIO_MIXER_H
#define AAUDIO_AAUDIO_MIXER_H

#include <stdint.h>

#include <aaudio/AAudio.h>
#include <fifo/FifoBuffer.h>

class AAudioMixer {
public:
    AAudioMixer() {}
    ~AAudioMixer();

    void allocate(int32_t samplesPerFrame, int32_t framesPerBurst);

    void clear();

    /**
     * Mix from this FIFO
     * @param fifo
     * @param volume
     * @return true if underflowed
     */
    bool mix(int trackIndex, android::FifoBuffer *fifo, float volume);

    void mixPart(float *destination, float *source, int32_t numFrames, float volume);

    float *getOutputBuffer();

private:
    float   *mOutputBuffer = nullptr;
    int32_t  mSamplesPerFrame = 0;
    int32_t  mFramesPerBurst = 0;
    int32_t  mBufferSizeInBytes = 0;
};


#endif //AAUDIO_AAUDIO_MIXER_H