effect of superformula.size doesn't seem predicable

Unless I'm missing something, `superforumla.size()` does not meanifully equate to 'squared pixels'. A circle with a given area (is that what 'square pixels' should be interpreted as?) is waaaaaaaay bigger than a rectangle.

I think this is probably a docs issue, but I'm left very confused as to how to lay out anything using superformula, as the sizes are so random.
