slime_equation_edit

function_dsl.r

# plus
"%+%" <- function(f, g) {
  return(paste0("(", f, ") * (", g,")"))
}

# minus
m <- function(f) {
  paste0( "-(", f, ")" )
}

# intersection
"%I%" <- function(f, g) {
  paste0( "min(", f, ",", g, ")" )
}

# cut
"%C%" <- function(f, g) {
  f %I% m(g)
}

mirror <- function(f) {
  gsub("x", "abs(x)", f)
}

union <- function(...) {
  paste0("MAX(", paste0(c(...), collapse=","), ")")
}

water <- function(f, g, depth) {
  paste0(f %+% g, "-", depth)
}

superellipse <- function(ox,oy,rx,ry,p) {
  xpart <- ifelse (ox == 0, "x", paste0("(x-",ox,")"))
  ypart <- ifelse (oy == 0, "y", paste0("(y-",oy,")"))
  paste0("(",xpart,"/",rx,")^", p, "+(",ypart,"/",ry,")^", p, "-1")
}

ellipse <- function(ox,oy,rx,ry) {
  superellipse(ox,oy,rx,ry,2)
}

function_viewer.r

library(rgl)

draw <- function(f_str, name="") {
  f_str <- gsub("MAX", "max", f_str)
  f_str <- gsub("--", "+", f_str)
  print(f_str)
  f <- parse(text=f_str)

  n <- 400
  #n <- 200
  xx <- seq(-150, 150, length = n)
  yy <- seq(-150, 150, length = n)

  zz <- outer(xx, yy, Vectorize(function(x, y) { eval(f) }))  

  #png(filename=paste0("png/graph_", name, ".png"), width=480, height=480)
  contour(xx, yy, zz, drawlabels=FALSE, levels=0, lwd=1, main=f)
  #dev.off()
  
  #png(filename=paste0("png/graph_", name, ".png"), width=480, height=480)
  #contour(xx, yy, zz, drawlabels=FALSE, levels=0, lwd=1)
  #dev.off()
  
  logz <- -log(-pmin(-zz,0)+1)

  clear3d(type = "all")
  par3d(windowRect=c(65,  52, 65+480, 52+480))
  light3d(diffuse="gray90", specular="gray90")
  bg3d("gray10")
  surface3d(xx, yy, logz, color = "#FFFFFF")
  #aspect3d(1,1,0.5)
  aspect3d(1,1,1)
  view3d(20, 10, zoom = 1)
  rgl.snapshot(paste0("png/snapshot_", name, ".png"))
}

main.r

rm(list=ls())

setwd('~/Dropbox/tech/function_draw/')

for (i in 1:100) {
  source('slime.r')
  Sys.sleep(5)
}

slime.r

source('function_dsl.r')
source('function_viewer.r')


horn <- ellipse( 0, 105, 8, 30)
face <- ellipse( 0,   0, 105, 75)
body <- water(horn, face, 1)

eye <- paste0("(", ellipse(27, 8, 15, 17), ")^2-1/3")
eyes <- mirror(eye)

mouse <- superellipse(0, -45, 67, 8, 4)
mouse <- gsub("y", "(y-(x/13)^2)", mouse)

slime <- (
  body %+% eyes %+% mouse
)

draw(slime, "slime")