lua-breakout/main.lua

Settings = {
	player_speed = 8,
	ball_speed = 5,

	block_rows = 3,
	block_cols = 8,

	block_height = 15,
	block_offset_x = 30,
	block_offset_y = 80,
	block_gap = 5,

	collision_margin = 2, -- kinda tied to ball radius lol
}

-- represenets the player-controlled paddle
Player = {
	x = 0,
	y = 0,
	width = 100,
	height = 10,
	moving_left = false,
	moving_right = false,
	-- Returns 2 values, x and y!
	getCenter = function()
		return Player.x + Player.width / 2, Player.y + Player.height / 2
	end,
}

Game = {
	ball = {
		position = { x = 0, y = 0 },
		velocity = { dx = 0, dy = 0 },
		radius = 5,
	},
	score = 0,
	-- Array of breakable blocks, generated on load!
	blocks = {},
	is_playing = true,
}

Assets = {}

function love.load()
	Assets.jirka = love.graphics.newImage("jirka.png")
	Assets.impact = love.audio.newSource("impact.ogg", "static")
	Assets.impact_wall = love.audio.newSource("impact_wall.ogg", "static")
	Assets.impact_player = love.audio.newSource("impact_player.ogg", "static")

	love.window.setTitle("Breakout")

	setupGame()
end

function love.update()
	if Game.is_playing == false then
		return
	end

	if Player.moving_left then
		Player.x = Player.x - Settings.player_speed
	end
	if Player.moving_right then
		Player.x = Player.x + Settings.player_speed
	end

	local b = Game.ball

	-- move ball
	b.position.x = b.position.x + b.velocity.dx
	b.position.y = b.position.y + b.velocity.dy

	-- Check wall collisions
	if b.position.x <= Settings.collision_margin then
		b.velocity.dx = -b.velocity.dx
		Assets.impact_wall:stop()
		Assets.impact_wall:play()
	end
	if b.position.x >= love.graphics.getWidth() - Settings.collision_margin then
		b.velocity.dx = -b.velocity.dx
		Assets.impact_wall:stop()
		Assets.impact_wall:play()
	end
	if b.position.y <= Settings.collision_margin then
		-- ceiling hit
		b.velocity.dy = -b.velocity.dy
		Assets.impact_wall:stop()
		Assets.impact_wall:play()
	end

	-- player collision
	if checkCollision(Player, Game.ball) then
		Assets.impact_player:play()
		b.velocity.dy = -b.velocity.dy
		local cx, cy = Player.getCenter()
		local distance_from_center = b.position.x - cx
		Game.ball.velocity.dx = (distance_from_center / (Player.width / 2)) * Settings.ball_speed
	end

	-- Check box collisions
	for _, block in ipairs(Game.blocks) do
		if block.active then
			local dist_x = block.x - b.position.x
			local dist_y = block.y - b.position.y
			if checkCollision(block, Game.ball) then
				block.active = false
				Assets.impact:stop()
				Assets.impact:play()

				Game.score = Game.score + 1

				-- block hit horizontal
				if b.position.x > (block.x + block.width) or b.position.x < block.x then
					b.velocity.dx = -b.velocity.dx
				else -- b.position.y > (block.y + block.height) or b.position.y < block.y then
					b.velocity.dy = -b.velocity.dy
				end
			end
		end
	end

	-- GAME OVER
	if b.position.y > love.graphics.getHeight() then
		love.event.quit(0)
	end

	-- WIN GAME??
	if Game.score == #Game.blocks then
		Game.is_playing = false
	end
end

function love.draw()
	if Game.is_playing == false then
		love.graphics.clear(0.1, 0.9, 0.3, 1)
		love.graphics.setColor(0, 0, 0, 1)
		love.graphics.print("YOU WON! GOOD JOB!", love.graphics.getWidth() / 2, love.graphics.getHeight() / 2)
		love.graphics.print(
			"Press space to play again",
			love.graphics.getWidth() / 2,
			(love.graphics.getHeight() / 2) + 30
		)
		love.graphics.setColor(255, 255, 255, 255) -- white?
		love.graphics.draw(Assets.jirka, (love.graphics.getWidth() / 2) - 150, (love.graphics.getHeight() / 2) - 70)

		return
	end
	love.graphics.setColor(1, 1, 1, 1) -- white
	love.graphics.clear()

	love.graphics.print("Score: " .. tostring(Game.score), 10, 10)

	love.graphics.rectangle("fill", Player.x, Player.y, Player.width, Player.height)

	-- draw the ball
	love.graphics.circle("fill", Game.ball.position.x, Game.ball.position.y, Game.ball.radius)

	-- draw the blocks
	for _, block in ipairs(Game.blocks) do
		if block.active then
			love.graphics.setColor(block.color.r, block.color.g, block.color.b)
			love.graphics.rectangle("fill", block.x, block.y, block.width, block.height, 4, 4)
		end
	end
end

-- INPUT HANDLING

function love.keypressed(key)
	if key == "left" or key == "a" then
		Player.moving_left = true
	end
	if key == "right" or key == "d" then
		Player.moving_right = true
	end
end

function love.keyreleased(key)
	if key == "left" or key == "a" then
		Player.moving_left = false
	end
	if key == "right" or key == "d" then
		Player.moving_right = false
	end

	if Game.is_playing == false and key == "space" then
		resetGame()
		Game.is_playing = true
	end
end

-- UTILS

function checkCollision(box, ball)
	local closestX = math.max(box.x, math.min(ball.position.x, box.x + box.width))
	local closestY = math.max(box.y, math.min(ball.position.y, box.y + box.height))

	local distanceX = ball.position.x - closestX
	local distanceY = ball.position.y - closestY

	local distanceSquared = (distanceX * distanceX) + (distanceY * distanceY)

	return distanceSquared < (ball.radius * ball.radius)
end

function setupGame()
	-- place the player
	Player.x = love.graphics.getWidth() / 2
	Player.y = love.graphics.getHeight() - 30

	-- place the ball
	local px, py = Player.getCenter()
	Game.ball.position.x = px
	Game.ball.position.y = py - Player.height
	Game.ball.velocity.dx = (love.math.random() - 0.5) * Settings.ball_speed
	Game.ball.velocity.dy = -Settings.ball_speed

	-- Setup block variables
	local cur_x = Settings.block_offset_x
	local cur_y = Settings.block_offset_y
	local gap = Settings.block_gap
	local block_width = (love.graphics.getWidth() - cur_x * 2 - gap * (Settings.block_cols - 1)) / Settings.block_cols
	-- Generate the actual blocks
	for row = 1, Settings.block_rows do
		for col = 1, Settings.block_cols do
			table.insert(Game.blocks, {
				x = cur_x,
				y = cur_y,
				width = block_width,
				height = Settings.block_height,
				color = {
					r = math.max(love.math.random(), 0.2),
					g = math.max(love.math.random(), 0.2),
					b = math.max(love.math.random(), 0.2),
				},
				active = true, -- This is turned off when a box is hit
			})
			cur_x = cur_x + block_width + gap
		end
		cur_y = cur_y + Settings.block_height + gap
		cur_x = Settings.block_offset_x
	end
end

function resetGame()
	-- Remove all blocks
	for k in pairs(Game.blocks) do
		Game.blocks[k] = nil
	end
	-- reset score
	Game.score = 0

	-- Reload
	setupGame()
end