rm(list = ls(all.names = TRUE))

library(plot3D)
library(tidyverse)

# set seed for repeating random values
set.seed(18)

# basic helix
t <- seq(1, 50, by = 0.01)
x <- 1000 * cos(2 * t) / (20 * t + t^2 / 2 + t^3 /100)
y <- 1000 * sin(2 * t) / (20 * t + t^2 / 2 + t^3 /100)
z <- t/5
dd <- data.frame(x, y, z)

# draw
jpeg("christmas_tree.jpg", width = 2400, height = 2400, res = 300)

# green part
dd1 <- dd %>% subset(z > 1.45) %>% subset(z < 8.4)
scatter3D(dd1$x, dd1$y, dd1$z, phi = 10, theta = 1, bty = "g",
          pch = 20, cex = 2, zlim = c(0, 10), xlim = c(-5, 5),
          ylim = c(-5, 5), col = "green")

# stem
dd2 <- dd %>% subset(z > 2.7) %>% subset(z < 5.1)
scatter3D(dd2$x, dd2$y, dd2$z - 2.8, phi = 10, theta = 1,
          bty = "g", pch = 20, cex = 2,
          add = T, col = "brown")

# star
scatter3D(0, 0, 8.8, phi = 10, theta = 1, bty = "g",
          pch = 8, cex = 4, add = T, col = "gold", lwd = 6)

# red balls
ss <- sample(x = 1:dim(dd1)[1], size = 25, 
             prob = 1 / dim(dd1)[1] + c(rep(1 / (2 * dim(dd1)[1]), dim(dd1)[1]/2), 
                                        rep(- 1 / (2 * dim(dd1)[1]), dim(dd1)[1]/2)))
dd3 <- dd1[ss, ]
scatter3D(dd3$x * 1.1, dd3$y * 1.1, dd3$z, phi = 10, theta = 1, bty = "g",
          pch = 20, cex = 3.5, add = T, col = "red")

dev.off()