main.hs

-- Balloons have x,y coordinates, a radius, and a color
data Balloon = Balloon {
    x :: Float,
    y :: Float,
    r :: Float,
    c :: Color
} deriving (Show)

main :: IO ()
main =
    let
        rng = mkStdGen 0
        world = Circle 60
        -- function to return a random color
        randColor = let colors = [red, green, blue, yellow, magenta, cyan]
                    in colors !! fst (randomR (0, 5) rng)

        -- list comprehension of 50 random x, y tuples
        circles :: [Balloon]
        circles = [Balloon { x=x, y=y, r=r, c=c } |
           x <- take 50 (randomRs (- 200, 200) rng),
           y <- take 50 (randomRs (- 200, 200) rng),
           r <- take 50 (randomRs (5, 15) rng),
           c <- replicate 50 randColor]

    in playIO
        (InWindow "Gloss" (200, 200) (10, 10))
        white
        60
        circles
        draw
        handleEvent
        update

drawCircle (Balloon x y r c ) =
    translate x y $ color red $ circleSolid r

draw :: Monad m0 => [Balloon] -> m0 Picture
draw = return . pictures . map drawCircle

--- handle escape and quit
handleEvent (G.EventKey (G.SpecialKey G.KeyEsc) G.Down _ _) _ = exitSuccess
handleEvent _ c = return c

update t = return