boring-game-0.1.0.1: src/Pong.hs

{-|
Module      : Pong
Description : GameState management
Copyright   : (c) Truong Dung, 2017
License     : GPL-3
Maintainer  : checkraiser11@gmail.com
Stability   : experimental
Portability : POSIX
-}
module Pong(
  PongGame,
  ballLoc,
  ballVel,
  render, 
  initialState
) where

import Graphics.Gloss
-- | Data describing the state of the pong game
data PongGame = Game
  { ballLoc :: (Float, Float) -- ^ Pong ball (x, y) location
  , ballVel :: (Float, Float) -- ^ Pong ball (x, y) velocity
  , player1 :: Float -- ^ Left player paddle height
  , player2 :: Float -- ^ Right player
  } deriving Show


-- | The initial state for the game of Pong
initialState :: PongGame
initialState = Game
  { ballLoc = (-10, 30)
  , ballVel = (1, -10)
  , player1 = 40
  , player2 = -80
  }

-- | Convert a game state into a picture
render :: PongGame -- ^ The game state to render.
          -> Picture -- ^ A picture of this game state.
render game =
  pictures [ball, walls,
          mkPaddle rose 120 $ player1 game,
          mkPaddle orange (-120) $ player2 game]

  where
    -- the pong ball.
    ball = uncurry translate (ballLoc game) $ color ballColor $ circleSolid 10
    ballColor = dark red

    -- the bottom and top walls.
    wall :: Float -> Picture
    wall offset = translate 0 offset $
                    color wallColor $
                      rectangleSolid 270 10

    wallColor = greyN 0.5
    walls = pictures [wall 150, wall (-150)]

    -- make a paddle of a given border and vertical offset.
    mkPaddle :: Color -> Float -> Float -> Picture
    mkPaddle col x y = pictures
      [ translate x y $ color col $ rectangleSolid 26 86
      , translate x y $ color paddleColor $ rectangleSolid 20 80
      ]

    paddleColor = light $ light blue