---

gapeaudiooutput.cpp

//gapeaudiooutput.cpp
//Dave Chisholm dkc@ccrma.stanford.edu 12/1/00
#include "gapeaudiooutput.h"

GapeAudioOutput::GapeAudioOutput(GapeController* c, int numChannels, int device)
: GapeUnit(c, numChannels) {
    properlyInitialized = true;
    if (numChannels > GAPE_MAX_NUM_CHANNELS) {
        numChannels = GAPE_MAX_NUM_CHANNELS;
        GapeConsts::reportError("GapeAudioOutput does not support the requested number of channels - the max number of channels is being used instead. Redefine GAPE_MAX_NUM_CHANNELS and re-compile if necesary.");
    }
    try {
        output = new RtAudio(numChannels, GapeConsts::sampleRate, "play", device);
    } catch (StkError& e) {
        QString message("GapeAudioOutput - unable to initialize - ");
        message.append(e.getMessage());
        GapeConsts::reportError(message.latin1());
        properlyInitialized = false;
    }
    soundBufferSize =   GAPE_RT_IO_BUFFER_SIZE * numChannels;
    soundBuffer = new GapeIntSample[soundBufferSize];
    currentBufferPosition = 0;
    //setNumChannels(numChannels);
}

GapeAudioOutput::~GapeAudioOutput() {
    if (currentBufferPosition != 0) {
        output->playBuffer(soundBuffer, currentBufferPosition);
    }
    delete []soundBuffer;
    soundBuffer = NULL;
    delete output;
    output = NULL;
}


void GapeAudioOutput::setMute(bool b) {
    if (muted == b) return;
    if (b) {
        stop();
    } else {
        start();
    }
    muted = b;
    emit emitMute(b);
}


void GapeAudioOutput::stop() {
    #ifdef DIRECTX_API
        output->stopPlay();
    #endif
}


void GapeAudioOutput::start() {
    #ifdef DIRECTX_API
        output->startPlay();
    #endif
}



void GapeAudioOutput::receiveTick(const GapeFloat* values, int numValues) {
    static bool wrongNumberOfChannelsFlag = false;
    static bool waitingForGoodInput = false;
    static bool properInitializtionReportedFlag = false;
    int numToCopy, i;
    //char error[256];
//sprintf(error,"GAO rectick values[0] = %f, num val = %d\n",values[0],numValues);
//GapeConsts::reportError(error);


//this next bit of code works around the property of windows audio where if it recieves no new input,
//it will repeat the last buffer of data over and over again. We try to intelligently see if our sound has
//been muted or otherwise shut off, and (temporarily) stop the windows audio thread if necesary
//I also considered just sending zeros to the windows audio thread. Hmm.
    if ((values == NULL) || (numValues == 0)) {
        if (!waitingForGoodInput) {
            output->playBuffer(soundBuffer, soundBufferSize);
            currentBufferPosition = 0;
            stop();
            waitingForGoodInput = true;
            GapeConsts::reportError("GapeAudioOutput received a null tick and muted itself!\n");
        }
        emit emitTick(values, numValues);
        return;

    } else {
        if (waitingForGoodInput) {
            GapeConsts::reportError("GapeAudioOutput unmuted itself\n");
            start();
            waitingForGoodInput = false;
        }
    }

    if (!properlyInitialized) {
            if (!properInitializtionReportedFlag) {
                properInitializtionReportedFlag = true;
                GapeConsts::reportError("GapeAudioOutput was not properly initialized - *not* outputting sound to DAC!\n");
            }
        emit emitTick(values, numValues);
        return;
    }

    if (muted) {
            emit emitTick(values, numValues);
            return;
    }

    if (numValues == numChannels) {//if we have the right # of channels just play the sample and then emit it
        while (numValues > 0) {//some logic to ensure we have no buffer overflows
            if (numValues < (soundBufferSize - currentBufferPosition)) {
                numToCopy = numValues;
            } else {
                numToCopy = soundBufferSize - currentBufferPosition;
            }
            for (i = 0; i < numToCopy; i++) {
                soundBuffer[currentBufferPosition + i] = GapeConsts::floatToInt(values[i]);//convert to integer and store
            }
            currentBufferPosition += numToCopy;
            numValues -= numToCopy;
            if (currentBufferPosition == (soundBufferSize)) {//if our internal buffer is full, we play the sample
                output->playBuffer(soundBuffer, soundBufferSize);
                currentBufferPosition = 0;
            }
        }/*
        for (i = 0;i < numValues; i++)
            soundBuffer[currentBufferPosition++] = (short)(values[i] * 32000.0);
        if (currentBufferPosition == (soundBufferSize - 1)) {//if our internal buffer is full, we play the sample
            output->playBuffer(soundBuffer, soundBufferSize);
            currentBufferPosition = 0;
        }*/
        emit emitTick(values,numValues);

    } else {//otherwise, we must copy the data into an acceptably sized sample
        GapeFloat sample[GAPE_MAX_NUM_CHANNELS] = {0.0};//this will init everything to 0

        if (!wrongNumberOfChannelsFlag) {//print an error if we haven't already
            GapeConsts::reportError("GapeAudioOutput was sent the wrong number of channels to play!\n");
            wrongNumberOfChannelsFlag = true;
        }

        if (numValues > numChannels) {//if we have too much data, only use as many channels as we can handle
            for (i = 0; i < numChannels; i++) {
                sample[i] = values[i];
            }

        } else {//otherwise, only copy in the valid data, and leave the rest of the channels at 0
            for (i = 0; i < numValues; i++) {
                sample[i] = values[i];
            }
        }
        receiveTick(sample, numChannels);//neatly use recursion to handle our acceptable converted sample
    }
}

---