Lua Love2D dungeon generator

dungen.lua

function mkroom(x, y, w, h, id)
	local room = {
		x = x,
		y = y,
		w = w,
		h = h,
		adj = {},
		id = id or 0
		};	

	return room
end

function roomcoll(a, b, margin)
	margin = margin or 10
	if a == b then return false else
		return math.abs(a.x - b.x) < (a.w + b.w) / 2 + margin and  math.abs(a.y - b.y) < (a.h + b.h) / 2 + margin
	end
end

function spread(x, y, r, cnt)
	local rooms = {}
	for i = 1, cnt do
		local ang = love.math.random() * 2 * math.pi
		local r = love.math.random() * r
		local x = x + math.floor(math.cos(ang) * r)
		local y = y + math.floor(math.sin(ang) * r)
		local w = math.floor(love.math.random(15, 60))
		local h = math.floor(love.math.random(15, 60))
		rooms[i] = mkroom(x, y, w, h, i)
	end
	return rooms
end

function cleanup(rooms, cnt)
	for i = #rooms, 1, -1 do
		for j = #rooms, 1, -1 do
			if rooms[i] and rooms[j] and roomcoll(rooms[i], rooms[j]) == true then
				table.remove(rooms, j)
			end
		end
	end
	
	cnt = #rooms - cnt
	for i = 1, cnt do
		table.remove(rooms, 1)
	end
	
	return rooms
end

function mknet(rooms)
	local net = {}
	for i = 1, #rooms do
		for j = 1, #rooms do
			if i ~= j then
				local dist = math.sqrt((rooms[i].x - rooms[j].x) ^ 2 + (rooms[i].y - rooms[j].y) ^ 2) 
				net[#net + 1] = {rooms[i], rooms[j], dist = dist, act = true}
				table.insert(rooms[i].adj, rooms[j])
				table.insert(rooms[j].adj, rooms[i])
			end
		end
	end
	return net
end

function spantree(rooms, net)
	function fill(rooms, idtar, idnew)
		for i = 1, #rooms do
			if rooms[i].id == idtar then
				rooms[i].id = idnew
			end
		end
	end
	
	function getmin(net)
		local best = 10e9
		local besti = 0
		for i = 1, #net do
			local conn = net[i]
			if conn.dist < best then
				best = conn.dist
				besti = i
			end
		end
		return besti
	end
	
	local done = {}
	
	while #net > 0 do
		local besti = getmin(net)
		local best = net[besti]	
		if best[1].id ~= best[2].id then
			fill(rooms, best[1].id, best[2].id)
			done[#done + 1] = best
		end
		table.remove(net, besti)
	end
	
	return done
end

--Please note, that each corridor can be represented with a room as well!
function net2halls(net)
	local halls = {}
	
	for i = 1, #net do
		local conn = net[i]
		local a = conn[1]
		local b = conn[2]
		
		local mx, my
		if love.math.random() < 0.5 then
			mx = a.x
			my = b.y
		else
			mx = b.x
			my = a.y
		end
		
		halls[#halls + 1] = {a.x, a.y, mx, my, b.x, b.y}
	end
	
	return halls
end

function generate()
	rooms = spread(400, 300, 200, 100)
	rooms = cleanup(rooms, 20)
	net = mknet(rooms)
	net = spantree(rooms, net)
	halls = net2halls(net)
end


function love.load()
	love.window.setMode(800, 600, {msaa = 0})
	love.window.setTitle("Dungeon generator")
	generate()
	shownet = false
end

function love.keypressed(key, scancode, isrepeat)
	if key == "space" then
		generate()
	end
	
	if key == "n" then
		shownet = not shownet
	end
end

function love.draw()
	--Draw corridors
	love.graphics.setLineWidth(5)
	love.graphics.setColor(40, 100, 140, 255)
	for i = 1, #halls do
		love.graphics.line(halls[i])
	end
	
	--Draw rooms
	love.graphics.setLineWidth(3)
	for i = 1, #rooms do
		love.graphics.setColor(40, 80, 120, 255)
		love.graphics.rectangle("fill", rooms[i].x - rooms[i].w / 2, rooms[i].y - rooms[i].h / 2, rooms[i].w, rooms[i].h)
		love.graphics.setColor(40, 100, 140, 255)
		love.graphics.rectangle("line", rooms[i].x - rooms[i].w / 2, rooms[i].y - rooms[i].h / 2, rooms[i].w, rooms[i].h)
	end
	
	--Draw net (debug only)
	if shownet == true then
		love.graphics.setLineWidth(1)
		love.graphics.setColor(200, 200, 200, 128)
		for i = 1, #net do
			love.graphics.line(net[i][1].x, net[i][1].y, net[i][2].x, net[i][2].y)
		end
	end
end