Function process

fmod/src/spatialize_effect.cpp:1024–1298

}

FMOD_RESULT F_CALL process(FMOD_DSP_STATE* state,
                           unsigned int length,
                           const FMOD_DSP_BUFFER_ARRAY* inBuffers,
                           FMOD_DSP_BUFFER_ARRAY* outBuffers,
                           FMOD_BOOL inputsIdle,
                           FMOD_DSP_PROCESS_OPERATION operation)
{
    auto effect = reinterpret_cast<State*>(state->plugindata);

    auto sourceCoordinates = calcCoordinates(effect->source.absolute);
    auto listenerCoordinates = calcListenerCoordinates(state);

    if (operation == FMOD_DSP_PROCESS_QUERY)
    {
        if (!initFmodOutBufferFormat(inBuffers, outBuffers, state, effect->outputFormat))
            return FMOD_ERR_DSP_DONTPROCESS;

        if (inputsIdle)
        {
            if (effect->hasTail)
            {
                effect->shouldProcessTail = true;
            }
            else
            {
                // if the sound is idle, we still need to check the expected overall gain to help manage
                // channel counts. updateOverallGain won't do any processing - just determine how loud
                // the sound would be (according to attenuation, etc) if it were playing.
                // Note: the SteamAudio Unity plugin now calculates iplGetDirectSoundPath so this is even lighter
                updateOverallGain(state, sourceCoordinates, listenerCoordinates);
                return FMOD_ERR_DSP_DONTPROCESS;
            }
        }
    }
    else if (operation == FMOD_DSP_PROCESS_PERFORM)
    {
        updateOverallGain(state, sourceCoordinates, listenerCoordinates);

        auto samplingRate = 0;
        auto frameSize = 0u;
        state->functions->getsamplerate(state, &samplingRate);
        state->functions->getblocksize(state, &frameSize);

        auto numChannelsIn = inBuffers->buffernumchannels[0];
        auto numChannelsOut = outBuffers->buffernumchannels[0];
        auto in = inBuffers->buffers[0];
        auto out = outBuffers->buffers[0];

        // Start by clearing the output buffer.
        memset(out, 0, numChannelsOut * frameSize * sizeof(float));

        // Make sure that audio processing state has been initialized. If initialization fails, stop and emit silence.
        // TODO: if nothing is initialized, do some fallback processing (passthrough, panning, or something like that).
        auto initFlags = lazyInit(state, numChannelsIn, numChannelsOut);
        if (!(initFlags & INIT_DIRECTAUDIOBUFFERS) || !(initFlags & INIT_BINAURALEFFECT) || !(initFlags & INIT_DIRECTEFFECT))
            return FMOD_ERR_DSP_SILENCE;

        if (gNewHRTFWritten)