Method ProcessPreview

engine/PoseidonOpenAL/SoundSystemOAL.cpp:1262–1341

    const float seekTo = audio::DevicePreviewOffsetSeconds(now, _devicePreviewAnchorMs, _devicePreviewLengthSec);
    // Stash the seek on the wave so DoPlay applies it once the AL
    // source actually exists (Play() defers to next Commit, so
    // alSourcef here would no-op against a 0 source).
    if (auto* w = dynamic_cast<WaveOAL*>(wave))
        w->_pendingSeekSeconds = seekTo;
    wave->Play();

    LOG_DEBUG(Audio, "StartDevicePreview: playing '{}' from offset {:.2f}s (anchor={}ms)",
              static_cast<const char*>(name), seekTo, _devicePreviewAnchorMs);
}

void SoundSystemOAL::ProcessPreview()
{
    if (!_doPreview)
        return;

    uint32_t now = GlobalTickCount();
    if (now < _previewTime)
        return;

    float deltaT = 0.1f;

    if (!_previewSpeech)
    {
        SoundPars pars{};
        ResolvePreviewSoundArray("speech", pars);
        RStringB name = pars.name;
        LOG_DEBUG(Audio, "Preview: loading speech '{}'", static_cast<const char*>(name));
        IWave* wave = CreateWave(name, false, true);
        _previewSpeech = wave;
        if (wave)
        {
            wave->SetKind(WaveSpeech);
            wave->EnableAccommodation(false);
            wave->SetSticky(true);
            wave->SetVolume(pars.vol, pars.freq, true);
            wave->Repeat(1);
            wave->Play();
        }
        else
        {
            LOG_WARN(Audio, "Preview: failed to create speech wave '{}'", static_cast<const char*>(name));
            _doPreview = false;
        }
    }
    else if (PreviewAdvance(_previewSpeech, deltaT) && !_previewEffect)
    {
        SoundPars pars{};
        ResolvePreviewSoundArray("effect", pars);
        RStringB name = pars.name;
        LOG_DEBUG(Audio, "Preview: loading effect '{}'", static_cast<const char*>(name));
        IWave* wave = CreateWave(name, true, false);
        _previewEffect = wave;
        if (wave)
        {
            wave->EnableAccommodation(false);
            wave->SetSticky(true);
            wave->SetVolume(pars.vol, pars.freq, true);
            wave->SetPosition(_listenerPos + _listenerDir * 50, _listenerVel, true);