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module Main where
import Prelude
import Math (sin)
import Data.Maybe (Maybe(..))
import Data.Array ((..))
import Data.Foldable (fold)
import Data.Int (toNumber)
import Control.Monad.Eff (Eff())
import Control.Timer (Timer())
import Signal ((~>), Signal(), runSignal)
import Signal.DOM (animationFrame)
import DOM (DOM())
import Graphics.Canvas (
Canvas(), Context2D(),
getCanvasElementById, getContext2D, clearRect,
Rectangle()
)
import Graphics.Drawing.Color (rgb)
import Graphics.Drawing (
render, translate,
Drawing(), Shape(),
circle, fillColor, filled
)
canvasConfig :: { boundaries :: Rectangle }
canvasConfig = {
boundaries: {
x: 0.0, y: 0.0,
w: 800.0, h: 500.0
}
}
dotConfig = {
separation: spacing + maxSize,
horizontal: 20,
vertical: 15,
maxSize,
minSize: 5.0,
color: rgb 200.0 220.0 210.0
}
where
spacing = 5.0
maxSize = 20.0
graphicsOrigin = {
x: (canvasConfig.boundaries.w - ((toNumber dotConfig.horizontal) * dotConfig.separation)) / 2.0,
y: (canvasConfig.boundaries.h - ((toNumber dotConfig.vertical) * dotConfig.separation)) / 2.0
}
renderDot :: Number -> Number -> Number -> Drawing
renderDot x y r =
filled (fillColor dotConfig.color) dot
where
dot :: Shape
dot = circle x y r
renderDots :: Int -> Int -> Number -> Number -> Drawing
renderDots xn yn spacing diameter = fold dots
where
places :: Array { x :: Int, y :: Int }
places = (\x y -> { x, y }) <$> 0 .. (xn - 1) <*> 0 .. (yn - 1)
coord { x, y } = { x: x' * spacing, y: y' * spacing }
where x' = toNumber x
y' = toNumber y
coords :: Array { x :: Number, y :: Number }
coords = coord <$> places
dot { x, y } = renderDot x y (diameter / 2.0)
dots = dot <$> coords
pulse :: forall eff. Number -> Number -> Eff (dom :: DOM, timer :: Timer | eff) (Signal Number)
pulse min max = do
nowMs <- animationFrame
return $ nowMs ~> amp
where secs ms = ms / 1000.0
unitAmp x = ((sin x) + 1.0) / 2.0
amp ms = (unitAmp $ secs ms) * (max - min) + min
rendering :: forall eff. Context2D -> Number -> Eff (canvas :: Canvas | eff) Unit
rendering ctx n = do
let dotGraphics = renderDots dotConfig.horizontal dotConfig.vertical dotConfig.separation n
graphics = translate graphicsOrigin.x graphicsOrigin.y dotGraphics
clearRect ctx canvasConfig.boundaries
render ctx graphics
main :: forall eff. Eff ( timer :: Timer, dom :: DOM, canvas :: Canvas | eff) Unit
main = do
Just canvas <- getCanvasElementById "dot-waves"
ctx <- getContext2D canvas
p <- pulse dotConfig.minSize dotConfig.maxSize
runSignal $ p ~> (rendering ctx)