// Plot implements the Plot method of the plot.Plotter interface.
func (bs *Bubbles) Plot(da plot.DrawArea, plt *plot.Plot) {
trX, trY := plt.Transforms(&da)
da.SetColor(bs.Color)
for _, d := range bs.XYZs {
x := trX(d.X)
y := trY(d.Y)
if !da.Contains(plot.Point{x, y}) {
continue
}
rad := bs.radius(d.Z)
// draw a circle centered at x, y
var p vg.Path
p.Move(x+rad, y)
p.Arc(x, y, rad, 0, 2*math.Pi)
p.Close()
da.Fill(p)
}
}