## R for aRt examples


## SECTION 1

## FROM: https://www.r-graph-gallery.com/132-sunshine-dataart

par(mar=c(0,0,0,0))   # all four margins are set to zero; default margin is 1 inch
pie(abs(rnorm(100)), radius=10, border="transparent", xlim=c(0,5))

# abs(rnorm(100)) returns absolute positive values of 100 random numbers in normal distribution
# radius = 10 indicates the radius of the circle of the pie chart as 10 (normally 1, which generates a circular pie)
# border = transparent results in no borders are drawn between slices of the pie 
# xlim=c(0,5) limits the piechart to the values 0 to 5 

## * * * * * * * * * * * * * * * * * 

## SECTION 2

## FROM: http://www.r-graph-gallery.com/57-rays-abstract-painting/
## generate pairs of x-y values
theta = seq(0, pi, length = 300)
x = cos(theta)
y = sin(theta)

## set graphical parameters
op = par(bg = "black", mar = rep(0.5, 4))

## plot
plot(x, y, type = 'n')
segments(rep(0, 299), rep(0, 299), x[1:299] * runif(299, 0.7), 
         y[1:299] * runif(299, 0.7), 
         col = hsv(runif(299, 0.45, 0.55), 1, 1, runif(299, 0.5)), 
         lwd = 5*runif(299))

## signature
legend("topleft", legend = "19 Nisan 2019", bty = "n", text.col = "gray70")

## * * * * * * * * * * * * * * * * * 

## SECTION 3

## https://fronkonstin.com/2016/03/01/a-silky-drawing-and-a-tiny-experiment 
## The code below is the corrected one from the same page

library(magrittr)
library(ggplot2)
opt = theme(legend.position  = "none",
            panel.background = element_rect(fill="violetred4"),
            axis.ticks       = element_blank(),
            panel.grid       = element_blank(),
            axis.title       = element_blank(),
            axis.text        = element_blank())
W = seq(from=-10, to=10, by = 0.05)
D8 = data.frame(expand.grid(x=W, y=W))
ggplot(data=D8, aes(x=(x+3*sin(y)), y=(y+3*cos(x)))) +  geom_point(alpha=.1, shape=20, size=1, color="white") + opt

## * * * * * * * * * * * * * * * * * 

## SECTION 4

## https://fronkonstin.com/2014/10/01/complex-domain-coloring/ 

require(ggplot2)
f = function(x) (1+1i)*log(sin((x^3-1)/x))
z=as.vector(outer(seq(-5, 5, by =.01),1i*seq(-5, 5, by =.01),'+'))
z=data.frame(x=Re(z),
             y=Im(z),
             h=(Arg(f(z))<0)*1+Arg(f(z))/(2*pi),
             s=(1+sin(2*pi*log(1+Mod(f(z)))))/2,
             v=(1+cos(2*pi*log(1+Mod(f(z)))))/2)
z=z[is.finite(apply(z,1,sum)),]
opt=theme(legend.position="none",
          panel.background = element_blank(),
          panel.grid = element_blank(),
          axis.ticks=element_blank(),
          axis.title=element_blank(),
          axis.text =element_blank())
ggplot(data=z, aes(x=x, y=y)) + geom_tile(fill=hsv(z$h,z$s,z$v))+ opt

## * * * * * * * * * * * * * * * * * 

## SECTION 5

## title: "Reproducible psychedelic art with R: a tribute to spatstat"
## author: "Petr Keil"
## installing the "spatstat" package
## install.packages("spatstat")

## Loading the `spatstat` library
library(spatstat)

## Defining the 2:3 window
W23 <- as.owin(list(xrange=c(0,3), yrange=c(0,2)))

## Figure 1 (http://www.petrkeil.com/?p=2707)
## Generate the patterns:
set.seed(1612)

# The exponent
Lambda <- 5
# Lay down the longest lines
main.lines <- psp(runif(3),runif(3),runif(3),runif(3), window=W23)

# Sample points proportionally to the distance to the lines
dist.from.line <- distmap(main.lines)
# exponential transformation of the distance
dist.from.line.exp <- Lambda*exp(-Lambda*dist.from.line)

samp.pois <- rpoispp(dist.from.line.exp*15)

# Project to the lines using project2segment(b, a)
Xproj <- project2segment(samp.pois, main.lines)$Xproj
sub.lines <- psp(samp.pois$x, samp.pois$y, Xproj$x, Xproj$y, window=W23)

# Connect with the lines
all.lines <- append.psp(main.lines, sub.lines)
dist.from.all.lines <- distmap(all.lines, dimyx=c(1200, 800))

# FIGURE 1:
par(mai=c(0,0,0,0))
dist.from.all.lines.exp <- exp(-Lambda*dist.from.all.lines)
plot(dist.from.all.lines.exp, 
     legend=FALSE, main="", box=FALSE, ribbon=FALSE)
contour(dist.from.all.lines.exp, add=TRUE, col="white")
contour(dist.from.all.lines, col="black", add=TRUE, lwd=4, levels=0.2)
contour(dist.from.all.lines, col="black", add=TRUE, lwd=2, levels=0.3)
contour(dist.from.all.lines, col="black", add=TRUE, lwd=2)
plot(sub.lines, add=T, lty=2, col="black", lwd=1)
plot(main.lines, add=T, col="black", lwd=4)

# FIGURE 2:
# Generate the pattern:

set.seed(16211)
rc <- rpoispp(function(x,y){50 * exp(-3*(max(y)-y))}, 100, win=W23)
rcdist <- distmap(rc, dimyx=c(1200, 800))
rc2 <- rpoispp(1/rcdist*50)
rcd <- dirichlet(rc2)
# To see the art on the screen, do not use the first and last lines of the following block.
par(mai=c(0,0,0,0))
plot(rcdist, legend=FALSE, main="", frame=FALSE, box=FALSE, ribbon=FALSE)
plot(rcd, add=T)
plot(rc, add=T, col="black", pch=19, cex=2.5)
plot(rjitter(rc, 0.01), add=T, col="white", pch=19, cex=0.4)
contour(rcdist, add=T, col="white")

## * * * * * * * * * * * * * * * * * 

## SECTION 6

## FROM: http://www.r-graph-gallery.com/55-double-heart-abstract-painting 

# generate pairs of x-y values

theta = seq(-2 * pi, 2 * pi, length = 300)
x = cos(theta)
y = x + sin(theta) 

# set graphical parameters
op = par(bg = "black", mar = rep(0.1, 4))
# For white background: op = par(bg = "white", mar = rep(0.1, 4)) 

# generate pairs of x-y values

theta = seq(-2 * pi, 2 * pi, length = 300)
x = cos(theta)
y = x + sin(theta) 

# set graphical parameters

op = par(bg = "black", mar = rep(0.1, 4))

# plot

plot(x, y, type = "n", xlim = c(-8, 8), ylim = c(-1.5, 1.5))
for (i in seq(-2*pi, 2*pi, length = 100))
{
  lines(i*x, y, col = hsv(runif(1, 0.85, 0.95), 1, 1, runif(1, 0.2, 0.5)), 
        lwd = sample(seq(.5, 3, length = 10), 1))          
}

# signature
legend("bottomright", legend = "19 Nisan 2019", bty = "n", text.col = "gray70")