Rで放射線マークを描く

クラフトワーク来日記念にRで放射線マークを描いてみました。
参考：三つ葉マ－クと放射線

par(bg = "yellow")
x0 <- seq(-2,2,0.001)
y0 <- sqrt(2^2 - x0^2)
x1 <- seq(10*cos(pi/3), 10, 0.01)
y1 <- sqrt(10^2 - x1^2)
x2 <- seq(3*cos(pi/3), 3, 0.01)
y2 <- sqrt(3^2 - x2^2)
x3 <- seq(-3*cos(pi/3),3*cos(pi/3),0.01)
y3 <- -sqrt(3^2 - x3^2)
x4 <- seq(-10*cos(pi/3),10*cos(pi/3),0.01)
y4 <- -sqrt(10^2 - x4^2)

plot(NULL, xlim = c(-13,13), ylim = c(-13,13), frame.plot = FALSE, axes = FALSE,xlab = "", ylab = "")
polygon(c(x0,rev(x0)),c(y0, rev(-y0)), col = "black")
polygon(c(3,10,rev(x1),x2,3),c(0,0,rev(y1),y2,0), col = "black")
polygon(-c(3,10,rev(x1),x2,3),c(0,0,rev(y1),y2,0), col = "black")
polygon(c(x3, rev(x4)), c(y3, rev(y4)), col = "black")

#お好みで以下を追加
x5 <- seq(-11,11,0.001)
y5 <- sqrt(11^2 - x5^2)
x6 <- seq(-13,13,0.001)
y6 <- sqrt(13^2 - x6^2)
polygon(c(x5,rev(x5),x6,rev(x6)),c(y5,-rev(y5),y6,-rev(y6)), col = "red", border = "red")
lines(c(11*cos(pi/4),-11*cos(pi/4)),c(11*cos(pi/4),-11*cos(pi/4)), lwd=40, col = "red")