シューティングゲーム

# include <Siv3D.hpp>

void Main()
{
    Window::SetTitle(L"Siv Shooting | [Z]: shot / 十字キー: 移動");

    const Texture texture(Image(640, 960,[n = PerlinNoise()](auto p)
    {
        return HSV(220, 0.9 * n.octaveNoise0_1(p.x / 160.0, Abs(p.y / 120.0 - 4.0), 8), 0.8);
    }));

    const Font font(20);
    Array<Vec2> shots, bullets, enemies;
    Triangle player(300, 200, 20.0);
    int32 count = 0, crash = 0, score = 0, highSore = 0;

    while (System::Update())
    {
        ++count;

        const int32 skyOffset = System::FrameCount() % 960 * 8;
        texture(0, -skyOffset / 2, 640, 480).draw();
        texture(0, -skyOffset, 640, 480).draw(Alpha(80));

        if (count % (24 - Min(count / 60, 18)) == 0)
            enemies.emplace_back(Random(40, 600), -40);

        Vec2 dir(Input::KeyRight.pressed - Input::KeyLeft.pressed, Input::KeyDown.pressed - Input::KeyUp.pressed);

        if (!dir.isZero())
            player.moveBy(dir.setLength(Input::KeyShift.pressed ? 4.5 : 9.0));

        player.setCentroid(Clamp(player.centroid().x, 0.0, 640.0), Clamp(player.centroid().y, 0.0, 480.0));

        if (Input::KeyZ.pressed && count % 4 == 0)
            shots.push_back(player.p0);

        for (auto& shot : shots)
            shot.y -= 8.0;

        for (auto& bullet : bullets)
            bullet.y += 4.0;

        for (auto& enemy : enemies)
        {
            enemy.y += 2.0;

            if (count % 60 == 0)
                bullets.push_back(enemy);
        }

        if (AnyOf(bullets, [=](const Vec2& b) { return player.intersects(b); })
            || AnyOf(enemies, [=](const Vec2& e) { return e.y > 490.0; }))
        {
            count = score = 0;
            crash = 60;
        }

        Erase_if(shots, [](const Vec2& s) { return s.y < -10.0; });

        Erase_if(bullets, [](const Vec2& b) { return b.y > 490.0; });

        Erase_if(enemies, [&](const Vec2& e) {
            if (AnyOf(shots, [=](const Vec2& s) { return e.distanceFrom(s) < 20.0; }))
            {
                ++score;
                return true;
            }
            else return e.y > 490.0;
        });

        for (const auto& shot : shots)
            Circle(shot, 7).drawFrame(4, 0, Palette::Orange);

        for (const auto& bullet : bullets)
            Circle(bullet, 4).draw();

        for (const auto& enemy : enemies)
            RectF(30, 30).setCenter(enemy).rotated(enemy.y / 100.0).draw(Palette::Black);

        player.draw();

        if (crash)
            Window::ClientRect().draw(Alpha(--crash * 3));

        font(L"Hi:{}\n{}"_fmt, highSore = Max(score, highSore), score).draw(20, 20);
    }
}