floraloverlay.r

library(magick)

# This is the function for the basic shape
flower <- function(a){
  # make an index
  t <- seq(0,202,l=499)
  # make a curve
  z1 <- (1i*(1i^a)*cos(2*t*pi)*(1) + 1*(1i^a)*(sin(2*t*pi))*(1) )
  # modulate the curve
  z1*(3+(sin(a*Arg(z1))*cos(a*Arg(z1))*cos((10-a)*Arg(z1))))
}

# Rotate the end point to the front for segments.
rot <- function(x) c(x[-1],x[1])

# Function to make each image
makeFlower <- function(h=0,filename,N=9){
  png(filename, type="cairo",width=1000,height=1000)
  par(mfrow=c(sqrt(N),sqrt(N)), 
      oma=10*rep(1,4), 
      mar=0*rep(1,4),bg="#f0f0f0")
  for(i in 1:N) {
    h = h
    s = 0.9
    v = .5
    alpha = 0.3
    col = hsv(h,s,v,alpha)
    z = flower(a=i/2)
    plot(z, type="o", asp=1, pch=20, 
         axes=F, ann=F, col=col, lwd=0.1)
    # We use segments not lines in case 
    # we want to vary the col throughout.
    segments(Re(z),Im(z),rot(Re(z)),rot(Im(z)), col=col)
    points(z, col=hsv(h,0,1,.4))
    }
  dev.off()
}

# Make four layers
makeFlower( 1,"fl4.png",16)
makeFlower(.8,"fl3.png",9)
makeFlower(.6,"fl2.png",4)
makeFlower(.5,"fl1.png",1)

# Compose final image using imagemagick

fl1 <- image_read("fl1.png")
fl2 <- image_read("fl2.png")|> 
  image_transparent("#f0f0f0")
fl3 <- image_read("fl3.png")|> 
  image_transparent("#f0f0f0")
fl4 <- image_read("fl4.png") |> 
  image_transparent("#f0f0f0")
fl1 |> 
  image_composite(fl2) |>
  image_composite(fl3) |>
  image_composite(fl4) |> 
  image_write("fl0.png")