circleFloor

local tArgs = {...}
local dim = tonumber( tArgs[1] )
local startDir = tArgs[2] == "l"

local coord = { 0, 0, 0 }
local dir = 0

coord[1] = math.ceil( -dim / 2 )
coord[3] = math.ceil( -dim / 2 )
local startCoord = { coord[1], coord[2], coord[3] }

if not startDir then coord[3] = -coord[3] end

function curMoveAxis()
   if dir % 2 == 0 then
      return 1
   else
      return 3
   end
end
function curMoveDir()
   if math.floor( dir / 2 ) % 2 == 0 then
      return 1
   else
      return -1
   end
end

function forward()
   while not turtle.forward() do sleep( 1 ) end

   local axis = curMoveAxis()
   coord[ axis ] = coord[ axis ] + curMoveDir()
end
function backward()
   while not turtle.back() do sleep( 1 ) end

   local axis = curMoveAxis()
   coord[ axis ] = coord[ axis ] - curMoveDir()
end
function turnLeft()
   turtle.turnLeft()
   dir = ( dir + 1 ) % 4
end
function turnRight()
   turtle.turnRight()
   dir = ( dir - 1 ) % 4
end
function turn( _dir )
   if _dir then
      turnLeft()
   else
      turnRight()
   end
end

function moveToSlot( to, fromMin, fromMax )
   if not fromMax then fromMax = 16 end

   for i = fromMin, fromMax do
      if turtle.getItemCount( to ) == 64 then break end

      if not i == to and turtle.getItemCount( i ) > 0 then
         turtle.select( i )
         turtle.transferTo( to, 64 )
      end
   end

   turtle.select( to )
end

function inRange()
   return coord[1] * coord[1] + coord[3] * coord[3] < ( dim / 2 ) * ( dim / 2 )
end

for i = 1, dim do
   local hasPlaced = false
   print("Nextline")

   while inRange() or not hasPlaced do
      if inRange() then
         --print( "!!", coord[1], coord[3] )
         moveToSlot( 1, 2 )
         turtle.placeDown()
         hasPlaced = true
      end

      forward()
   end

   turn( startDir )
   forward()
   turn( startDir )

   while inRange() do
      backward()
   end

   startDir = not startDir
end

function sign( t )
   if t < 0 then return -1 else return 1 end
end
function stepsToPos( newCoord )
   local axis = curMoveAxis()

   return ( coord[ axis ] - newCoord[ axis ] ) * curMoveDir()
end
function moveTo( newCoord )
   for i = 1, 2 do
      local axis = curMoveAxis()

      while stepsToPos( newCoord ) > 0 do
         backward()
      end
      while stepsToPos( newCoord ) < 0 do
         forward()
      end

      if i == 1 then turn(true) end
   end
   turn(false)
end

moveTo( startCoord )