VisualSound with SFML

VisualSound.cpp

#include <deque>
#include <mutex>
#include <SFML/Audio.hpp>
#include <SFML/Graphics.hpp>

class MusicVisualizer : public sf::Music, public sf::Drawable
{
public:
    void update(const sf::Time& deltaTime);

protected:
    [[nodiscard]] bool onGetData(Chunk& data) override;

    void draw(sf::RenderTarget& target, sf::RenderStates states) const override;

private:
    std::recursive_mutex m_mutex;
    std::deque<std::uint16_t> m_queue;
    std::vector<sf::Vertex> m_vertices;
};

bool MusicVisualizer::onGetData(Chunk& data)
{
    auto result = Music::onGetData(data);

    {
        std::lock_guard lock(m_mutex);

        for (auto i = 0u; i < data.sampleCount; ++i)
        {
            m_queue.emplace_back(data.samples[i]);
        }
    }

    return result;
}

void MusicVisualizer::draw(sf::RenderTarget& target, sf::RenderStates states) const
{
    target.draw(m_vertices.data(), m_vertices.size(), sf::PrimitiveType::Points, states);
}

void MusicVisualizer::update(const sf::Time& deltaTime)
{
    m_vertices.clear();

    {
        std::lock_guard lock(m_mutex);

        auto size = std::min(static_cast<unsigned int>(m_queue.size()), 1920u);
        m_vertices.reserve(size);

        for (auto i = 0u; i < size; ++i)
        {
            auto vertex = sf::Vertex{ {static_cast<float>(i), 0.01f * static_cast<float>(m_queue[i]) + 200.f}, sf::Color::Green};
            m_vertices.emplace_back(vertex);
        }
    }

    for (auto i = 0u; !m_queue.empty() && i < static_cast<unsigned int>(deltaTime.asSeconds() * getSampleRate() * getChannelCount()); ++i)
    {
        m_queue.pop_front();
    }
}

int main()
{
    auto window = sf::RenderWindow{ sf::VideoMode{ { 1920u, 1080u } }, "CMake SFML Project" };
    window.setFramerateLimit(144);

    auto visualizer = MusicVisualizer();
    if (!visualizer.openFromFile("epic-hollywood-trailer-9489.mp3"))
    {
        return -1;
    }

    visualizer.setLoop(true);
    visualizer.play();

    auto clock = sf::Clock{};

    while (window.isOpen())
    {
        for (auto event = sf::Event{}; window.pollEvent(event);)
        {
            if (event.type == sf::Event::Closed)
            {
                window.close();
            }
        }

        auto deltaTime = clock.restart();
        visualizer.update(deltaTime);

        window.clear();
        window.draw(visualizer);
        window.display();
    }
}