BTW, I registered an account and logged in, but I post as a guest. Is there something else I must to to post as a
user, or is there just a delay?

You should be able to post as a registered (wikidot) user. When you're logged in, and you try to post something, you should not see fields such as name, email id etc on the posting page (those show up for anonymous users only).

Try again (maybe after restarting your browser), and let's see if it works out for you…

It's almost scary to see someone using the Canvas API to such good effect - I have not had a chance to put in too much work at all into the implementation of that API.

If you identify anything that you consider to be pretty useful that is missing from the API, do let me know.

render (0) { cos _ andThen abs andThen f }

BTW, I registered an account and logged in, but I post as a guest. Is there something else I must to to post as a user, or is there just a delay?

import Math._ import java.awt.Color._ clear invisible val width = 180 val height = 25 val halfwave = Vector.tabulate(width){ i => toRadians(i) } def render (level: Int)(fn: Double => Double) { val y0 = level * height val y1 = (level + 1) * height (halfwave map fn zipWithIndex) foreach { case(e, i) => val c = e.toFloat Canvas.setPenColor(new Color(c, c, c)) Canvas.line(i, y0, i, y1) } } val f = { x: Double => 1 - x } render (3) { sin } render (2) { sin _ andThen f } render (1) { cos _ andThen abs } render (0) { cos _ andThen abs andThen { x => 1 - x } }