clustering.cpp

#include <Siv3D.hpp>
#include <HamFramework.hpp>
#include <queue>

constexpr int PanelSize = 6;
constexpr int Wall = std::numeric_limits<int>::max() / 2;
constexpr int Shortest = Wall / 2;
constexpr Point FieldSize(100, 100);

Grid<int> map;
Array<Point> breakwall;

constexpr std::array<Point, 4u> Surround = { Point::Up(), Point::Left(), Point::Down(), Point::Right() };

void Main()
{
	map.resize(FieldSize);
	int number = 1;
	map.fill(Wall);

	Point rb;
	for (int i = 0; i < map.width(); ++i)
	{
		for (int k = 0; k < map.height(); ++k)
		{
			map[k][i] = Wall;
			if ((1 <= i&&i < map.width() - 1) && (1 <= k && k < map.height() - 1))
			{
				if ((i % 2) && (k % 2))
				{
					map[k][i] = number++;
					rb = { i, k };
				}
				else if ((i % 2) ^ (k % 2) && (i < map.width() - 2) && (k < map.height() - 2))
				{
					if (i % 2)
					{
						map[k][i] = -1;
					}
					else
					{
						map[k][i] = -2;
					}
					breakwall.emplace_back(Point(i, k));
				}
			}
		}
	}
	breakwall.shuffle();

	for (auto& pos : breakwall)
	{
		int info1, info2;

		if (map[pos] == -1)
		{
			info1 = map[pos.movedBy(0, 1)];
			info2 = map[pos.movedBy(0, -1)];

		}
		else if (map[pos] == -2)//よこ
		{
			info1 = map[pos.movedBy(1, 0)];
			info2 = map[pos.movedBy(-1, 0)];
		}

		if (info1 != info2 || RandomBool(0.015))
		{
			std::queue<Point> qu;
			map[pos] = info1;
			qu.push(pos);

			while (qu.size())
			{
				const auto basepos = qu.front();

				for (const auto& surrond : Surround)
				{
					const auto pos = basepos.movedBy(surrond);
					auto& hoge = map[pos];
					if (hoge != info1 &&
						hoge != Wall &&
						0 < hoge)
					{
						hoge = info1;
						qu.push(pos);
					}
				}
				qu.pop();
			}
		}
		else
		{
			map[pos] = Wall;
		}
	}

	{
		Grid<Point> parent(map.size());
		parent.fill(Point::Zero());
		std::queue<Point> search;
		search.push({ 1,1 });
		map[search.front()] = 0;
		while (true)
		{
			if (search.front() == rb)
			{
				break;
			}

			for (const auto& surround : Surround)
			{
				const auto pos = search.front().movedBy(surround);
				if (map[pos] != 0 && map[pos] != Wall && parent[pos] == Point::Zero())
				{
					parent[pos] = search.front();
					map[pos] = 0;
					search.push(pos);
				}
			}
			search.pop();
		}

		Point marking = rb;
		while (marking != Point::Zero())
		{
			map[marking] = Shortest;
			marking = parent[marking];
		}
	}

	Camera2D camera;
	Font font(20);

	while (System::Update())
	{
		camera.update();
		{
			auto hoge = camera.createTransformer();
			auto piyo = ScalableWindow::CreateTransformer();

			for (int i = 0; i < map.width(); ++i)
			{
				for (int k = 0; k < map.height(); ++k)
				{
					Color color;
					switch (map[k][i])
					{
					case Shortest:
						color = (KeyZ.pressed() ? Palette::Red : Palette::White);
						break;
					case Wall:
						color = Palette::Darkgray;
						break;
					default:
						color = Palette::White;
						break;
					}
					Rect((i)* PanelSize, (k)* PanelSize, PanelSize).draw(color);
				}
			}
		}
		camera.draw();
		ScalableWindow::DrawBlackBars();
	}
}