There's probably a better way to choose which points go above and below than random(), but it works.
Edit: Got it to work non-randomly. Adjacent dots alternate above and below: http://vicapow.github.io/equation-plot-webgl/index.html#0.5%...
http://vicapow.github.io/equation-plot-webgl/index.html#0.48...)
http://vicapow.github.io/equation-plot-webgl/index.html#0.48...)