geoscan

local component = require("component")

if not component.isAvailable("geolyzer") then

  io.stderr:write("This program requires a Geolyzer to run.\n")

  return

end

if not component.isAvailable("hologram") then

  io.stderr:write("This program requires a Hologram Projector to run.\n")

  return

end
local geolyzer =component.geolyzer
local hologram =component.hologram

local sx, sz = 48, 48

local ox, oz = -24, -24

local starty, stopy = -5



local function validateY(value, min, max, default)

  value = tonumber(value) or default

  if value < min or value > max then

    io.stderr:write("invalid y coordinate, must be in [" .. min .. ", " .. max .. "]\n")

    os.exit(1)

  end

  return value

end



do

  local args = {...}

  starty = validateY(args[1], -32, 31, starty)

  stopy = validateY(args[2], starty, starty + 32, math.min(starty + 32, 31))

end



hologram.clear()

for x=ox,sx+ox do

  for z=oz,sz+oz do

    local hx, hz = 1 + x - ox, 1 + z - oz

    local column = geolyzer.scan(x, z, false)

    for y=1,1+stopy-starty do

      local color = 0

      if column then

        local hardness = column[y + starty + 32]

        if hardness == 0 or not hardness then

          color = 0

        elseif hardness < 3 then

          color = 2

        elseif hardness < 100 then

          color = 1

        else

          color = 3

        end

      end

      if hologram.maxDepth() > 1 then

        hologram.set(hx, y, hz, color)

      else

        hologram.set(hx, y, hz, math.min(color, 1))

      end

    end

    os.sleep(0)

  end

end