Improve testing of initial render for CircleRenderer, verify idempotence, refactor to reuse a complicated fn
Improve testing of initial render for CircleRenderer, verify idempotence, refactor to reuse a complicated fn

gdseller/plottable,alyssaq/plottable,onaio/plottable,iobeam/plottable,palantir/plottable,danmane/plottable,iobeam/plottable,palantir/plottable,palantir/plottable,danmane/plottable,jacqt/plottable,RobertoMalatesta/plottable,RobertoMalatesta/plottable,NextTuesday/plottable,NextTuesday/plottable,iobeam/plottable,palantir/plottable,jacqt/plottable,danmane/plottable,onaio/plottable,alyssaq/plottable,softwords/plottable,NextTuesday/plottable,jacqt/plottable,onaio/plottable,RobertoMalatesta/plottable,gdseller/plottable,alyssaq/plottable,softwords/plottable,gdseller/plottable,softwords/plottable