#!/usr/local/bin/Rscript
# ^--- UNIXovy hashbang pro R pkg na macOS

# velikost obrazku (px)
px = 1280 + 90
py = 960 + 135

# PARAMETRY OBRAZKU
X = -0.5
Y = 0.0
R = 1.5

# rozliseni a pocet iteraci
resolution = 2000 
n = 750

# vystupni adresar
dir = "vzorecek"

#-------------------------------------------------------------------------------

# nastaveni parametru do vypoctu
xcen = X
ycen = Y
regionsize = 2*R

#-------------------------------------------------------------------------------

# custom barevna skala
barvy <- c(
  colorRampPalette(c("#e7f0fa", "#c9e2f6", "#95cbee",
                     "#0099dc", "#4ab04a", "#ffd73e"))(0.1 * n),
  colorRampPalette(c("#eec73a", "#e29421", "#e29421", 
                     "#f05336","#ce472e"), bias=2)(0.9 * n), 
  "black")

#-------------------------------------------------------------------------------

# snimek - pro pouziti ve smycce
filenamenum = 1000
png(paste(dir, "/", "frame-", filenamenum, ".png", sep="", collapse = NULL), px, py)	

# region (1:1 pro w<h obrazky)
xregion = regionsize * 1
yregion = regionsize * py/px
	
# shodne rozliseni pro oba smery
nx = resolution * 1
ny = resolution * py/px
	
# stred regionu - nastaveni okoli
xmin = xcen - xregion/2
xmax = xcen + xregion/2
ymin = ycen - yregion/2
ymax = ycen + yregion/2

# souradnice (od-do po nx a ny krocich)
x <- seq(xmin, xmax, length.out=nx)
y <- seq(ymin, ymax, length.out=ny)

# inicializace komplexniho cisla C (x + yi)
c <- outer(x, y * 1i, FUN="+")

# inicializace vystupnich matic - Z (hodnota) a K (stupen) = 0.0
z <- matrix(0.0, nrow=length(x), ncol=length(y))
k <- matrix(0.0, nrow=length(x), ncol=length(y))

#-------------------------------------------------------------------------------	

# VLASTNI VYPOCET

# vzoreckove dobrodruzstvi - pro kazde N
for (krok in 1:n) {
	print(paste(krok, "(", filenamenum, ")", sep = "", collapse = NULL))
	
	# iterace pro oba smery v ramci jednoho N
	for (j in 1:ny) {
		for (i in 1:nx) {
			
			# overeni mezi komplexniho cisla
			if (Mod(z[i, j]) < 2 && k[i, j] < n) {
			
				# z1 = z0*z0 + c
				z[i, j] <- z[i, j]^2 + c[i, j]
				
				# stupen se zvysuje o 1
				k[i, j] <- k[i, j] + 1
			}
			
		}
	}
}

#-------------------------------------------------------------------------------

# zapis obrazku a zavreni bufferu (useRaster - starsi verze R jinak glitchuji)
image(x, y, k, col=barvy, useRaster = TRUE)
dev.off()