Clear canvas correctly after resize

Author: sharkdp

src/Flare/Drawing.purs

@@ -29,10 +29,9 @@ runFlareDrawing controls canvasID ui = do
   let canvas = unsafePartial (fromJust mcanvas)
   ctx <- getContext2D canvas
 
-  w <- getCanvasWidth canvas
-  h <- getCanvasHeight canvas
-
   let render' drawing = do
+        w <- getCanvasWidth canvas
+        h <- getCanvasHeight canvas
         clearRect ctx { x: 0.0, y: 0.0, w, h }
         render ctx drawing