, 20,-05,-10,-30, -40) * width  + 50
y <- c(-20, -20,  0,  5, 20, 20,  5,  0, -20) * height + 50
wheel.size <- height

,  0,  5, 20, 20,  5,  0, -20) * height + 50
wheel.size <- height * 10 + 5
ymin <- min(y); xmin <- min(x); xmax <- max