sbuilde

-- Dome and sphere builder.
-- Copyright (C) 2012 Timothy Goddard
--
-- Permission is hereby granted, free of charge, to any person obtaining a copy of
-- this software and associated documentation files (the "Software"), to deal in
-- the Software without restriction, including without limitation the rights to
-- use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
-- the Software, and to permit persons to whom the Software is furnished to do so,
-- subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be included in all
-- copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-- FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
-- COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
-- IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
--
-- usage: sdbuild <type> <radius> [-c]
-- type should be either dome or sphere
-- radius is distance from centre - total width is actually 2 * radius + 1
-- the structure will be built with its lowest point on the level the turtle is at
-- the block the turtle starts on will be the horizontal centre
-- if -c is passed, will only calculate number of blocks required and not build

local arg = { ... }

type = arg[1]
radius = tonumber(arg[2])

cost_only = false
blocks = 0

clear_blocks = true
ender_fill = true

if arg[3] == "-c" then
  cost_only = true
end

-- Navigation features
-- allow the turtle to move while tracking its position
-- this allows us to just give a destination point and have it go there

positionx = radius
positiony = radius
facing = 0

function turnRightTrack()
  turtle.turnRight()
  facing = facing + 1
  if facing >= 4 then
    facing = 0
  end
end

function turnLeftTrack()
  turtle.turnLeft()
  facing = facing - 1
  if facing < 0 then
    facing = 3
  end
end

function safeForward()
  success = false
  while not success do
    success = turtle.forward()
    if not success then
      if clear_blocks then
        turtle.select(15)
        turtle.attack()
        turtle.dig()
        turtle.drop()
        turtle.select(1)
      else
        print("Blocked attempting to move forward.")
        print("Please clear and press enter to continue.")
        io.read()
      end
    end
  end
end

function safeBack()
  success = false
  while not success do
    success = turtle.back()
    if not success then
          if clear_blocks then
            turtle.select(15)
            turtle.turnLeft()
            turtle.turnLeft()
            turtle.attack()
            turtle.dig()
            turtle.drop()
            turtle.turnRight()
            turtle.turnRight()
            turtle.select(1)
          else
            print("Blocked attempting to move back.")
            print("Please clear and press enter to continue.")
            io.read()
          end
    end
  end
end

function safeUp()
  success = false
  while not success do
    success = turtle.up()
    if not success then
          if clear_blocks then
            turtle.select(15)
            turtle.attackUp()
            turtle.digUp()
            turtle.drop()
            turtle.select(1)
          else
            print("Blocked attempting to move up.")
            print("Please clear and press enter to continue.")
            io.read()
          end
    end
  end
end

function moveY(targety)
  if targety == positiony then
    return
  end

  if (facing ~= 0 and facing ~= 2) then -- check axis
    turnRightTrack()
  end

  while targety > positiony do
    if facing == 0 then
      safeForward()
    else
      safeBack()
    end
    positiony = positiony + 1
  end

  while targety < positiony do
    if facing == 2 then
      safeForward()
    else
      safeBack()
    end
    positiony = positiony - 1
  end
end

function moveX(targetx)
  if targetx == positionx then
    return
  end

  if (facing ~= 1 and facing ~= 3) then -- check axis
    turnRightTrack()
  end

  while targetx > positionx do
    if facing == 1 then
      safeForward()
    else
      safeBack()
    end
    positionx = positionx + 1
  end

  while targetx < positionx do
    if facing == 3 then
      safeForward()
    else
      safeBack()
    end
    positionx = positionx - 1
  end
end

function navigateTo(targetx, targety)
  -- Cost calculation mode - don't move
  if cost_only then
    return
  end

  if facing == 0 or facing == 2 then -- Y axis
    moveY(targety)
    moveX(targetx)
  else
    moveX(targetx)
    moveY(targety)
  end
end

cslot = 1
function placeBlock()
  -- Cost calculation mode - don't move
  blocks = blocks + 1
  if cost_only then
    return
  end

  if turtle.getItemCount(cslot) == 0 then
    foundSlot = false
    while not foundSlot do
      for i = 1,9 do
        if turtle.getItemCount(i) > 0 then
          foundSlot = i
          break
        end
      end
      if not foundSlot then
        if ender_fill then
          turtle.attackUp()
          turtle.digUp()
          turtle.select(16)
          turtle.placeUp()
          turtle.select(1)
          turtle.dropDown()
          turtle.suckUp()
          turtle.select(16)
          turtle.digUp()
          turtle.select(1)
        else
          -- No resources
          print("Out of building materials. Please refill and press enter to continue.")
          io.read()
        end
      end
    end
    cslot = foundSlot
    turtle.select(foundSlot)
  end

  turtle.placeDown()
end

-- Main dome and sphere building routine

width = radius * 2 + 1
sqrt3 = 3 ^ 0.5
boundary_radius = radius + 1.0
boundary2 = boundary_radius ^ 2

if type == "dome" then
  zstart = radius
elseif type == "sphere" then
  zstart = 0
else
  print("Usage: sdbuild <shape> <radius> [-c]")
  os.exit(1)
end
zend = width - 1

-- This loop is for each vertical layer through the sphere or dome.
for z = zstart,zend do
  if not cost_only then
    safeUp()
  end
  print("Layer " .. z)
  cz2 = (radius - z) ^ 2

  limit_offset_y = (boundary2 - cz2) ^ 0.5
  max_offset_y = math.ceil(limit_offset_y)

  -- We do first the +x side, then the -x side to make movement efficient
  for side = 0,1 do
    -- On the right we go from small y to large y, on the left reversed
    -- This makes us travel clockwise around each layer
    if (side == 0) then
      ystart = radius - max_offset_y
      yend = radius + max_offset_y
      ystep = 1
    else
      ystart = radius + max_offset_y
      yend = radius - max_offset_y
      ystep = -1
    end

    for y = ystart,yend,ystep do
      cy2 = (radius - y) ^ 2

      remainder2 = (boundary2 - cz2 - cy2)


      if remainder2 >= 0 then
        -- This is the maximum difference in x from the centre we can be without definitely being outside the radius
        max_offset_x = math.ceil((boundary2 - cz2 - cy2) ^ 0.5)

        -- Only do either the +x or -x side
        if (side == 0) then
          -- +x side
          xstart = radius
          xend = radius + max_offset_x
        else
          -- -x side
          xstart = radius - max_offset_x
          xend = radius - 1
        end

        -- Reverse direction we traverse xs when in -y side
        if y > radius then
          temp = xstart
          xstart = xend
          xend = temp
          xstep = -1
        else
          xstep = 1
        end

        for x = xstart,xend,xstep do
          cx2 = (radius - x) ^ 2
          distance_to_centre = (cx2 + cy2 + cz2) ^ 0.5
          -- Only blocks within the radius but still within 1 3d-diagonal block of the edge are eligible
          if distance_to_centre < boundary_radius and distance_to_centre + sqrt3 >= boundary_radius then
            offsets = {{0, 1, 0}, {0, -1, 0}, {1, 0, 0}, {-1, 0, 0}, {0, 0, 1}, {0, 0, -1}}
            for i=1,6 do
              offset = offsets[i]
              dx = offset[1]
              dy = offset[2]
              dz = offset[3]
              if ((radius - (x + dx)) ^ 2 + (radius - (y + dy)) ^ 2 + (radius - (z + dz)) ^ 2) ^ 0.5 >= boundary_radius then
                -- This is a point to use
                navigateTo(x, y)
                placeBlock()
                break
              end
            end
          end
        end
      end
    end
  end
end

-- Return to where we started in x,y place and turn to face original direction
-- Don't change vertical place though - should be solid under us!
navigateTo(radius, radius)
while (facing > 0) do
  turnLeftTrack()
end

print("Blocks used: " .. blocks)