# =============================================================
# Blue feathers
# =============================================================
# generate pairs of x-y values
x1 <- c(seq(0, pi, length = 50), seq(pi, 2*pi, length = 50))
y1 <- cos(x1) / sin(x1)
x2 <- seq(1.02 * 2 * pi + pi/2, 4*pi + pi/2, length = 50)
y2 <- tan(x2)
png("blue_feathers.png", width = 700, height = 400)
# set graphical parameters
op <- par(bg="black", mar=rep(.5,4))
# plot
plot(c(x1, x2), c(y1, y2), type = "n", ylim = c(-11, 11))
for (i in seq(-10, 10, length = 100))
{
lines(x1, y1 + i, col = hsv(runif(1, 0.65, 0.7), 1, 1, runif(1, 0.7)),
lwd = 4 * runif(1, 0.3))
lines(x2, y2 + i, col = hsv(runif(1, 0.65, 0.7), 1, 1, runif(1, 0.7)),
lwd = 4 * runif(1, 0.3))
}
# signature
legend("bottomright", legend = "© Gaston Sanchez", bty = "n",
text.col = "gray70")
# reset par
par(op)
dev.off()
