Add Coffeescript version of colorwheel.js.

ariya · Apr 22, 2011 · e1317ff · e1317ff
1 parent 3717373
commit e1317ff
Showing 1 changed file with 45 additions and 0 deletions.
diff --git a/examples/colorwheel.coffee b/examples/colorwheel.coffee
@@ -0,0 +1,45 @@
+if phantom.state.length is 0
+    phantom.state = 1
+    phantom.viewportSize = { width: 400, height : 400 }
+    phantom.content = '<html><body><canvas id="surface">' +
+        '</canvas></body></html>'
+else
+    el = document.getElementById 'surface'
+    context = el.getContext '2d'
+    width = window.innerWidth
+    height = window.innerHeight
+    cx = width / 2
+    cy = height / 2
+    radius = width / 2.3
+    i = 0
+
+    el.width = width
+    el.height = height
+    imageData = context.createImageData(width, height)
+    pixels = imageData.data
+
+    for y in [0...height]
+        for x in [0...width]
+            i = i + 4
+            rx = x - cx
+            ry = y - cy
+            d = rx * rx + ry * ry
+            if d < radius * radius
+                hue = 6 * (Math.atan2(ry, rx) + Math.PI) / (2 * Math.PI)
+                sat = Math.sqrt(d) / radius
+                g = Math.floor(hue)
+                f = hue - g
+                u = 255 * (1 - sat)
+                v = 255 * (1 - sat * f)
+                w = 255 * (1 - sat * (1 - f))
+                pixels[i] = [255, v, u, u, w, 255, 255][g]
+                pixels[i + 1] = [w, 255, 255, v, u, u, w][g]
+                pixels[i + 2] = [u, u, w, 255, 255, v, u][g]
+                pixels[i + 3] = 255
+
+    context.putImageData imageData, 0, 0
+    document.body.style.backgroundColor = 'white'
+    document.body.style.margin = '0px'
+
+    phantom.render 'colorwheel.png'
+    phantom.exit()