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@josefnpat josefnpat/conf.lua Secret
Last active Jan 14, 2020

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PÖNG - The Well Documented Version of PONG
function love.conf(t)
t.title = "PÖNG"
end
function love.load()
players = { -- init individual player controls
{ up = function() return love.keyboard.isDown("a") end,
down = function() return love.keyboard.isDown("z") end,},
{ up = function() return love.keyboard.isDown("up") end,
down = function() return love.keyboard.isDown("down") end}
}
for _,v in pairs(players) do -- init player vars
v.y = love.graphics.getHeight()/2 -- half way on the screen vertically
v.score = 0
end
paddle = { -- object for paddle config
width = 20, -- total width
height = 100, -- total height
speed = 300 -- 300px/second
}
ball = { -- object for ball config
-- normally, this would be the speed according to delta time (dt), so it would be 10px/s,
-- but to ensure accuracy of the paddle, we use 10px/frame.
-- The issue is that the speed may not exceed the paddle width, otherwise the ball
-- may skip over the paddle for large enough sizes of dt.
speed = 10, -- 10px/frame at ~60frames/second gives 600px/second
init = function() -- re-init the ball when player scores
ball.x = love.graphics.getWidth()/2 -- half way on the screen horizontally
ball.y = love.graphics.getHeight()/2 -- half way on the screen vertically
ball.vy = 0 -- velocity of the ball vertically
-- on reset, send the ball to the victor. If new game randomly choose a direction.
ball.direction = ball.direction and -ball.direction or math.random(0,1)*2-1
ball.wait = 1 -- amount of time to wait before serving the ball
end,
paddleCollide = function(player) -- when the ball is in the paddle section
if ball.y < player.y + paddle.height/2 and -- if ball is below the top of the paddle
ball.y > player.y - paddle.height/2 then -- and the ball is above the bottom of the paddle
ball.direction = ball.direction * -1 -- reverse the direction
-- use the difference of the center to amend the velocity of the ball vertically
ball.vy = ball.vy + (ball.y - player.y)/paddle.height*4
end
end,
playerScore = function(player) -- when the ball is in the score area
player.score = player.score + 1 -- increment player's score
ball.init() -- reset game
end
}
ball.init() -- new game
end
function love.draw()
for i,v in pairs(players) do -- for each player
love.graphics.rectangle("fill", -- draw the player's paddle
-- start x on the side determined by the index of the player
-- with the paddle's width as padding
(i-1)*(love.graphics.getWidth()-paddle.width),
v.y-paddle.height/2, -- start y above the current y by half the paddle height
paddle.width,paddle.height) -- draw the paddle width and height
end
love.graphics.circle("fill",ball.x,ball.y,4) -- draw the ball
love.graphics.printf(players[1].score..":"..players[2].score, -- draw the two scores
0,0,-- draw the score from the upper left
love.graphics.getWidth(),"center") -- define the width as the screen width and center it
end
function love.update(dt)
for i,v in pairs(players) do -- for each player
if v.up() then -- if the up button is pressed for current player
v.y = v.y - paddle.speed*dt -- move paddle up by paddle speed over dt (px/second)
end
if v.down() then -- if the down button is pressed for current player
v.y = v.y + paddle.speed*dt -- move paddle down by paddle speed over dt (px/second)
end
-- Clamp the top and bottom paddle movement, respectively.
if v.y < 0 then v.y = 0 end
if v.y > love.graphics.getHeight() then v.y = love.graphics.getHeight() end
end
if ball.wait then -- while waiting for the ball
ball.wait = ball.wait - dt -- subtract dt from waiting time
if ball.wait <= 0 then ball.wait = nil end -- clear wait when done
else -- not waiting for the ball
ball.x = ball.x + ball.speed*ball.direction -- move the ball's x by it's speed in it's direction
ball.y = ball.y + ball.vy -- move the ball's y by it's vertical velocity
if ball.y < 0 then -- if the ball hits the top
ball.y = -ball.y -- mirror the ball across the top
ball.vy = -ball.vy -- reverse the vertical velocity
elseif ball.y > love.graphics.getHeight() then -- if the ball hits the bottom
ball.y = ball.y - (ball.y - love.graphics.getHeight()) -- mirror across the bottom
ball.vy = -ball.vy -- reverse the vertical velocity
end
if ball.x > love.graphics.getWidth() then -- if ball in player 2 score area
ball.playerScore(players[1]) -- check player 1 score
elseif ball.x > love.graphics.getWidth() - paddle.width then -- if ball in player 2 paddle area
ball.paddleCollide(players[2]) -- check player 2 collision
elseif ball.x < 0 then -- if ball in player 1 score area
ball.playerScore(players[2]) -- check player 2 score
elseif ball.x < paddle.width then -- if ball in player 2 paddle area
ball.paddleCollide(players[1]) -- check player 1 collision
end
end
end
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