Method fillAudioBuffer

src/Abyss/AbyssEngine.cpp:250–277

ReSharper disable once CppDFAUnreachableFunctionCall - fillAudioBuffer is called via SDL2 audio callback

// ReSharper disable once CppDFAUnreachableFunctionCall - fillAudioBuffer is called via SDL2 audio callback
void AbyssEngine::fillAudioBuffer(Uint8 *stream, const int len) const {
    if (len & 1) {
        Common::Log::warn("Audio buffer length is not even, dropping samples...");
        std::fill_n(stream, len, 0);
        return;
    }

    for (auto i = 0; i < len; i += 2) {
        int32_t sample = 0;

        if (_videoStream != nullptr)
            sample += static_cast<int32_t>(static_cast<float>(_videoStream->getAudioSample()) * _videoAudioLevelActual);
        else if (_backgroundMusic != nullptr)
            sample += static_cast<int32_t>(static_cast<float>(_backgroundMusic->getSample()) * _backgroundMusicAudioLevelActual);

        for (const auto soundEffect : _soundEffects) {
            if (!soundEffect->getIsPlaying())
                continue;
            sample += static_cast<int32_t>(static_cast<float>(soundEffect->getSample()) * _soundEffectsAudioLevelActual);
        }

        sample = static_cast<int32_t>(static_cast<float>(sample) * _masterAudioLevelActual);

        sample = std::clamp(sample, -32768, 32767);
        stream[i] = sample & 0xFF;
        stream[i + 1] = (sample >> 8) & 0xFF;
    }
}

AbyssEngine &AbyssEngine::getInstance() {
    static AbyssEngine instance;