Canvas Example

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import Miso
import qualified Miso.Canvas as Canvas
import Miso.Canvas
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baseUrl :: MisoString
baseUrl = "https://7b40c187-5088-4a99-9118-37d20a2f875e.mdnplay.dev/en-US/docs/Web/API/Canvas_API/Tutorial/Basic_animations/"
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main :: IO ()
main =
  run $ do
    sun <- newImage (baseUrl <> "canvas_sun.png")
    moon <- newImage (baseUrl <> "canvas_moon.png")
    earth <- newImage (baseUrl <> "canvas_earth.png")
    startComponent (app sun moon earth) { initialAction = Just GetTime }
  where
    app sun moon earth = defaultComponent (0.0, 0.0) updateModel (view_ sun moon earth)
    view_ sun moon earth m =
      div_
      [ id_ "canvas grid" ]
      [ Canvas.canvas_
        [ id_ "canvas"
        , width_ "300"
        , height_ "300"
        ] (canvasDraw sun moon earth m n)
      | n <- [ 1 :: Int .. 4 ]
      ]
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canvasDraw :: Image -> Image -> Image -> (Double, Double) -> Int -> Canvas ()
canvasDraw sun moon earth (millis', secs') n = do
   let
     secs = secs' + fromIntegral n
     millis = millis' + fromIntegral n
   globalCompositeOperation DestinationOver
   clearRect (0, 0, 300, 300)
   fillStyle $ Canvas.color (rgba 0 0 0 0.6)
   strokeStyle $ Canvas.color (rgba 0 153 255 0.4)
   save ()
   translate (150, 150)
   rotate ((((2 * pi) / 60) * secs) + (((2 * pi) / 60000) * millis))
   translate (105,0)
   fillRect (0, -12, 50, 24)
   drawImage (earth, -12, -12)
   save ()
   rotate ((((2 * pi) / 6) * secs) + (((2 * pi) / 6000) * millis))
   translate (0, 28.5)
   drawImage (moon, -3.5, -3.5)
   replicateM_ 2 (restore ())
   beginPath ()
   arc (150, 150, 105, 0, pi * 2)
   stroke ()
   drawImage' (sun, 0, 0, 300, 300)