GnuPlot Universe

main.lua

love.window.setMode(1680,1050)

function gnuplot_reload()
  os.execute('gnuplot uni.plot')
  uniplot = love.graphics.newImage('uniplot.png')
end

function uni_reload()
  local uni_stat_map = love.image.newImageData('uni_stat_map.gif')
  package.loaded[ 'universegen' ] = nil
  unilib = nil
  unilib = require('universegen')
  uni = nil
  uni = unilib.new(uni_stat_map)
  uni:render()
  local f = io.open("data.csv",'w')
  f:write(uni:toPlot())
  f:close()
  gnuplot_reload()
end

function love.load()
  uni_reload()
end

function love.update(dt)
  
end

function love.draw()
  love.graphics.draw(uniplot)
end

function love.keypressed(key)

  if key == "r" then
    uni_reload()
  end

end

uni.plot

set datafile separator "," 
set view 30,60
splot 'data.csv' with points palette pt 8
set term pngcairo mono enhanced
set xlabel "X"
set ylabel "Y"
set zlabel "Z"
set terminal png size 1680,1050
set mouse
set xrange [-512:512]
set yrange [-512:512]
set zrange [-512:512]
set out 'uniplot.png'
replot

uni_stat_map.gif

universegen.lua

universegen = {}

function universegen.new(mapImageData,steps,ztight,bchance)
  local tmp = {}
  
  tmp.size = mapImageData:getWidth()
  
  tmp.report = 0.01
  
  tmp.steps = steps or 1024*8
  tmp.stepsTotal = tmp.steps
  tmp.zMult = ztight or 0.125
  tmp.bchance = bchance or 0.01
  
  tmp.map = mapImageData
  tmp.data = {}
  
  tmp.render = universegen.render
  tmp.attemptStep = universegen.attemptStep
  tmp.toPlot = universegen.toPlot
  tmp.addPoint = universegen.addPoint
  
  return tmp
end

function universegen.render(self)
  local curReport = self.report
  print("Rendering ..")
  while self.steps > 0 do
    if self:attemptStep() then
      self.steps = self.steps - 1
    end
    if self.steps/self.stepsTotal > curReport then
      print((curReport*100).."%")
      curReport = curReport + self.report
    end
  end
  print("Done.")
end

function universegen.attemptStep(self)
  local px,py = math.random(1,self.size-1),math.random(1,self.size-1)
  local pz = math.floor(
    math.sin(math.random()) * math.random(-self.size*self.zMult,self.size*self.zMult)
  )
  local r,g,b = self.map:getPixel(px,py)
  
  local rx,ry,rz = px-self.size/2,py-self.size/2,pz
  
  local mag = math.sqrt( rx^2 + ry^2 + rz^2) / self.size
  local calc_bchance = self.bchance * mag
  
  local map_chance = ((r+g+b)/3)/255
  
  local chance = calc_bchance + map_chance*(1-calc_bchance)
  
  if 1-math.cos(chance) > math.random() then
    return self:addPoint(rx,ry,rz)
  end
  return false
end

function universegen.addPoint(self,x,y,z)

  if not self.data[x] then
    self.data[x] = {}
  end

  if not self.data[x][y] then
    self.data[x][y] = {}
  end

  if not self.data[x][y][z] then
    self.data[x][y][z] = 1
    return true
  else
    self.data[x][y][z] = self.data[x][y][z] + 1
    return false
  end

end

function universegen.toPlot(self)
  local output = ""
  for x,vx in pairs(self.data) do
    for y,vy in pairs(vx) do
      for z,vz in pairs(vy) do
        output = output .. x .. ","..y..","..z.."\n"
      end
    end
  end
  return output
end

return universegen