mapArt (ComputerCraft)

-- +--------------------------------------------------------+
-- |                                                        |
-- |                         mapArt                         |
-- |                                                        |
-- +--------------------------------------------------------+

local version = "Version 1.1.1"

-- By Jeffrey Alexander, aka Bomb Bloke.
-- Command Computer script for building map images out of GIFs.
-- http://www.computercraft.info/forums2/index.php?/topic/28883-mapart/

---------------------------------------------
------------      Load APIs      ------------
---------------------------------------------

local function loadAPI(API, paste)
    if not _G[API] then
        if not (fs.exists(API) or fs.exists(shell.resolve(API))) then
            shell.run("pastebin get " .. paste .. " " .. API)
            os.loadAPI(shell.resolve(API))
        else os.loadAPI(fs.exists(API) and API or shell.resolve(API)) end
    end
end

loadAPI("bbpack", "cUYTGbpb")
loadAPI("GIF",    "5uk9uRjC")

---------------------------------------------
------------Variable Declarations------------
---------------------------------------------

local teleport = {commands.exec("tpn")}
teleport = (teleport[2][1]:sub(1, 16) == "Unknown command.") and "teleport" or "tpn"

local transparent = "minecraft:sandstone"

local x, y, z = commands.getBlockPosition()
local x1, z1 = math.floor((x - 64) / 128) * 128 + 64, math.floor((z - 64) / 128) * 128 + 64
local xSize, ySize, myEvent = term.getSize()
local startDir = shell.resolve(".")

---------------------------------------------
------------      Functions      ------------
---------------------------------------------

local function clear(textCol, backCol)
    if textCol then term.setTextColour(textCol) end
    if backCol then term.setBackgroundColour(backCol) end
    for i = 4, ySize - 3 do
        term.setCursorPos(1, i)
        term.clearLine()
    end
end

local function snooze()
    local myEvent = tostring({})
    os.queueEvent(myEvent)
    os.pullEvent(myEvent)
end

-- Returns whether a click was performed at a given location.
-- If one parameter is passed, it checks to see if y is [1].
-- If two parameters are passed, it checks to see if x is [1] and y is [2].
-- If three parameters are passed, it checks to see if x is between [1]/[2] (non-inclusive) and y is [3].
-- If four paramaters are passed, it checks to see if x is between [1]/[2] and y is between [3]/[4] (non-inclusive).
local function clickedAt(...)
    if myEvent[1] ~= "mouse_click" then return false end
    if #arg == 1 then return (arg[1] == myEvent[4])
    elseif #arg == 2 then return (myEvent[3] == arg[1] and myEvent[4] == arg[2])
    elseif #arg == 3 then return (myEvent[3] > arg[1] and myEvent[3] < arg[2] and myEvent[4] == arg[3])
    else return (myEvent[3] > arg[1] and myEvent[3] < arg[2] and myEvent[4] > arg[3] and myEvent[4] < arg[4]) end
end

-- Returns whether one of a given set of keys was pressed.
local function pressedKey(...)
    if myEvent[1] ~= "key" then return false end
    for i=1,#arg do if arg[i] == myEvent[2] then return true end end
    return false
end

-- Prompts user to select a file.
local function fileBrowser()
    local bump = math.floor((xSize - 49) / 2) + 1
    local cursor = {{">>  ","  <<"},{"> > "," < <"},{" >> "," << "},{"> > "," < <"}}
    local blackText = (_CC_VERSION or _HOST) and colours.grey or colours.black

    while true do
        local displayList, position, lastPosition, animationTimer, curCount, gapTimer, lastProgress = {}, 1, 0, os.startTimer(0), 1
        if #shell.resolve(".") > 0 then displayList[1] = ".." end

        do
            local fullList = fs.list(shell.resolve("."))
            table.sort(fullList, function (a, b) return string.lower(a) < string.lower(b) end)
            for i = 1, #fullList do if fs.isDir(shell.resolve(fullList[i])) then displayList[#displayList + 1] = fullList[i] end end
            for i = 1, #fullList do if fullList[i]:sub(#fullList[i] - 3):lower() == ".gif" then displayList[#displayList + 1] = fs.getName(fullList[i]) end end
        end

        while true do
            myEvent = {os.pullEvent()}

            -- Track animations (bouncing cursor + scrolling marquee).
            if myEvent[1] == "timer" and myEvent[2] == animationTimer then
                curCount = curCount == 4 and 1 or (curCount + 1)
                animationTimer = os.startTimer(0.5)
                myEvent[1] = "cabbage"

            -- Bail.
            elseif pressedKey(keys.backspace) or (myEvent[1] == "mouse_click" and myEvent[2] == 2) then
                return nil

            -- Move down the list.
            elseif pressedKey(keys.down, keys.s) or (myEvent[1] == "mouse_scroll" and myEvent[2] == 1) then
                position = position == #displayList and 1 or (position + 1)

            -- Move up the list.
            elseif pressedKey(keys.up, keys.w) or (myEvent[1] == "mouse_scroll" and myEvent[2] == -1) then
                position = position == 1 and #displayList or (position - 1)

            -- Select something.
            elseif pressedKey(keys.enter, keys.space) or clickedAt(math.floor(ySize / 2) + 1) then
                if fs.isDir(shell.resolve(displayList[position])) then
                    shell.setDir(shell.resolve(displayList[position]))
                    break
                else return shell.resolve(displayList[position]) end

            -- User clicked somewhere on the file list; move that entry to the currently-selected position.
            elseif clickedAt(0, xSize + 1, 3, ySize - 2) then
                position = position + myEvent[4] - math.floor(ySize / 2) - 1
                position = position > #displayList and #displayList or position
                position = position < 1 and 1 or position
            end

            -- Update other screen stuff.
            if myEvent[1] ~= "timer" then
                -- File list.
                term.setBackgroundColour(colours.black)
                for y = position == lastPosition and (math.floor(ySize / 2) + 1) or 4, position == lastPosition and (math.floor(ySize / 2) + 1) or (ySize - 3) do
                    local thisLine = y + position - math.floor(ySize / 2) - 1

                    if displayList[thisLine] then
                        local thisString = displayList[thisLine]
                        thisString = fs.isDir(shell.resolve(thisString)) and "["..thisString.."]" or thisString:sub(1, #thisString-4)

                        if thisLine == position then
                            term.setCursorPos(math.floor((xSize - #thisString - 8) / 2) + 1, y)
                            term.clearLine()
                            term.setTextColour(colours.red)
                            term.write(cursor[curCount][1])
                            term.setTextColour(colours.orange)
                            term.write(thisString)
                            term.setTextColour(colours.red)
                            term.write(cursor[curCount][2])
                        else
                            term.setCursorPos(math.floor((xSize - #thisString) / 2) + 1, y)
                            term.clearLine()

                            if y == 4 or y == ySize - 3 then
                                term.setTextColour(blackText)
                            elseif y == 5 or y == ySize - 4 then
                                term.setTextColour(term.isColour() and colours.grey or blackText)
                            elseif y == 6 or y == ySize - 5 then
                                term.setTextColour(term.isColour() and colours.lightGrey or colours.white)
                            else term.setTextColour(colours.white) end

                            term.write(thisString)
                        end
                    else
                        term.setCursorPos(1, y)
                        term.clearLine()
                    end
                end

                lastPosition = position
            end
        end
    end
end

-- Constructs image within the world.
local function doBuild(filename)
    local GIFImage, mapsX, mapsY, buildCount, myTimer = GIF.loadGIF(filename, "mapArt.pal"), 1, 1, 1
    local vert = GIFImage.height > GIFImage.width

    if vert then
        mapsX = math.ceil(GIFImage.width * mapsY / GIFImage.height)
    else
        mapsY = math.ceil(GIFImage.height * mapsX / GIFImage.width)
    end

    -- Bug the user about the output size:
    while true do
        clear(colours.black, colours.lightGrey)
        term.setCursorPos(21, 5)
        term.write("Resolution")
        term.setTextColour(colours.grey)
        term.setCursorPos(5, 7)
        term.write("Image resolution: " .. GIFImage.width .. " x " .. GIFImage.height .. ", ratio: " .. (GIFImage.width / GIFImage.height))
        term.setCursorPos(5, 9)
        term.write("Map resolution: " .. (mapsX * 128) .. " x " .. (mapsY * 128) .. ", ratio: " .. (mapsX / mapsY))
        term.setCursorPos(5, 11)
        term.write("Columns:")
        term.setCursorPos(5, 13)
        term.write("Rows:")
        term.setCursorPos(16, 11)
        term.write(mapsX)
        term.setCursorPos(16, 13)
        term.write(mapsY)
        term.setCursorPos(41, 11)
        term.write("Start")
        term.setCursorPos(39, 12)
        term.write("from map:")
        term.setCursorPos(42, 13)
        term.write(buildCount)

        term.setTextColour(colours.lightGrey)
        term.setBackgroundColour(colours.blue)
        term.setCursorPos(14, vert and 13 or 11)
        term.write("<")
        term.setCursorPos(19, vert and 13 or 11)
        term.write(">")
        term.setCursorPos(40, 13)
        term.write("<")
        term.setCursorPos(46, 13)
        term.write(">")
        term.setCursorPos(5, 15)
        term.write(" Back ")
        term.setCursorPos(40, 15)
        term.write(" Begin ")

        myEvent = {os.pullEvent()}

        if clickedAt(14, vert and 13 or 11) then
            if vert and mapsY > 1 then
                mapsY = mapsY - 1
                mapsX = math.ceil(GIFImage.width * mapsY / GIFImage.height)
            elseif not vert and mapsX > 1 then
                mapsX = mapsX - 1
                mapsY = math.ceil(GIFImage.height * mapsX / GIFImage.width)
            end
            if buildCount > mapsX * mapsY then buildCount = mapsX * mapsY end
        elseif clickedAt(19, vert and 13 or 11) then
            if vert and mapsY < 100 then
                mapsY = mapsY + 1
                mapsX = math.ceil(GIFImage.width * mapsY / GIFImage.height)
            elseif not vert and mapsX < 100 then
                mapsX = mapsX + 1
                mapsY = math.ceil(GIFImage.height * mapsX / GIFImage.width)
            end
        elseif clickedAt(40, 13) and buildCount > 1 then
            buildCount = buildCount - 1
        elseif clickedAt(46, 13) and buildCount < mapsX * mapsY then
            buildCount = buildCount + 1
        elseif clickedAt(4, 11, 15) then
            return
        elseif clickedAt(39, 47, 15) then
            break
        end
    end

    clear(colours.black, colours.lightGrey)

    term.setCursorPos(21, 5)
    term.write("Resizing...")

    for i = 2, #GIFImage do GIFImage[i] = nil end

    if GIFImage.width ~= mapsX * 128 and GIFImage.height ~= mapsY * 128 then
        if GIFImage.height > GIFImage.width then
            GIFImage = GIF.resizeGIF(GIFImage, nil, mapsY * 128)
        else
            GIFImage = GIF.resizeGIF(GIFImage, mapsX * 128)
        end
    end

    local image = {}
    for y = 1, GIFImage.height do
        image[y] = {}
        for x = 1, GIFImage.width do image[y][x] = 0 end
    end

    local pal, width, height = GIFImage.pal, GIFImage.width, GIFImage.height
    local len = #pal / 3
    GIFImage = GIFImage[1]

    for y = 1, GIFImage.yend do
        local x, GIFImageY, imageY = GIFImage.xstart + 1, GIFImage[y], image[y + GIFImage.ystart]
        for i = 1, #GIFImageY do
            local GIFImageYI = GIFImageY[i]
            if type(GIFImageYI) == "number" then
                x = x + GIFImageYI
            else
                for pixel = 1, #GIFImageYI do imageY[x + pixel - 1] = GIFImageYI[pixel] end
                x = x + #GIFImageYI
            end
        end
    end

    GIFImage = nil

    term.setCursorPos(21, 7)
    term.write("Padding...")

    if width < mapsX * 128 then
        local diff = mapsX * 128 - width
        for y = 1, height do
            local row = image[y]
            for i = 1, math.floor(diff / 2) do table.insert(row, 1, 0) end
            for i = #row + 1, #row + math.ceil(diff / 2) do row[i] = 0 end
            snooze()
        end
        width = mapsX * 128
    end

    if height < mapsY * 128 then
        local row = {}
        for i = 1, mapsX * 128 do row[i] = 0 end
        local diff = mapsY * 128 - height
        for i = 1, math.floor(diff / 2) do table.insert(image, 1, row) end
        for i = #image + 1, #image + math.ceil(diff / 2) do image[i] = row end
        height = mapsY * 128
        snooze()
    end

    -- Build stuff!
    for builds = buildCount, mapsX * mapsY do
        local xxxx, zzzz, curCommands, maxCommands, counter = (builds - 1) % mapsX, math.floor((builds - 1) / mapsX), 0, 250, 0

        clear(colours.black, colours.lightGrey)
        term.setCursorPos(22, 5)
        term.write("Building")
        term.setBackgroundColour(colours.grey)
        term.setCursorPos(4, 11)
        term.write(string.rep(" ", 45))
        term.setTextColour(colours.grey)
        term.setBackgroundColour(colours.lightGrey)

        sleep(0)

        parallel.waitForAny(
            -- Track completed commands.
            function()
                while true do
                    os.pullEvent("task_complete")
                    curCommands = curCommands - 1
                end
            end,

            -- Display build progress.
            -- Mostly pointless because server time pretty much stands still while this is running.
            function()
                local countmax, lastcount = 16640, 0

                repeat
                    myTimer = os.startTimer(60)
                    repeat local event, id = os.pullEvent("timer") until id == myTimer

                    term.setBackgroundColour(colours.brown)
                    term.setCursorPos(4, 11)
                    term.write(string.rep(" ", math.floor(counter / countmax * 45)))
                    term.setBackgroundColour(colours.grey)
                    term.write(string.rep(" ", 45 - math.floor(counter / countmax * 45)))

                    term.setBackgroundColour(colours.lightGrey)
                    term.setCursorPos(4, 7)
                    term.clearLine()
                    term.write(tostring(counter) .. " / " .. tostring(countmax) .. " blocks" .. (counter < countmax and ", ~" .. tostring(counter - lastcount) .. " per minute." or "."))
                    term.setCursorPos(4, 9)
                    term.clearLine()
                    term.write(counter < countmax and tostring(math.floor(counter / countmax * 100)) .. "%, about " .. tostring(math.ceil((countmax - counter) / (counter - lastcount))) .. " minutes remaining." or "100%")

                    lastcount = counter
                until counter == countmax
            end,

            -- Actual construction is done here.
            function()
                -- Prevent too many commands executing at once.
                local function doCommand(doThis)
                    while curCommands >= maxCommands do os.pullEvent("task_complete") end
                    commands.execAsync(doThis)
                    curCommands = curCommands + 1
                    counter = counter + 1
                end

                -- Clear old builds.
                doCommand("fill " .. x1 .. " 127 " .. (z1 - 1) .. " " .. (x1 + 127) .. " 128 " .. z1 .. " minecraft:air")
                for i = 1, 127 do doCommand("fill " .. x1 .. " " .. (127 - i) .. " " .. (z1 + i) .. " " .. (x1 + 127) .. " " .. (128 + i) .. " " .. (z1 + i) .. " minecraft:air") end

                -- Calibrate wave heights.
                local ys = {}
                for i = 1, 128 do
                    local y = (math.floor((image[1 + zzzz * 128][i + xxxx * 128] - 1) / len) == 0) and 127 or 128
                    doCommand("setblock " .. (x1 + i - 1) .. " " .. y .. " " .. (z1 - 1) .. " minecraft:cobblestone")
                    ys[i] = y
                end

                -- Main image area.
                for xxx = 0, 7 do for zzz = 0, 7 do for xx = 1, 16 do
                    local y = ys[xxx * 16 + xx]

                    for zz = 1, 16 do
                        local curCol = image[zz + zzz * 16 + zzzz * 128][xx + xxx * 16 + xxxx * 128]
                        local block = pal[curCol]

                        local shade = math.floor((curCol - 1) / len)
                        if shade == 0 then
                            y = y + 1
                        elseif shade == 2 then
                            y = y - 1
                        end

                        doCommand("setblock " .. (x1 + xx - 1 + xxx * 16) .. " " .. y .. " " .. (z1 + zz - 1 + zzz * 16) .. " " .. block[4] .. " " .. block[5])
                    end

                    ys[xxx * 16 + xx] = y
                end end end

                os.queueEvent("timer", myTimer)
                while true do os.pullEvent("stopResumingMe") end
            end
        )

        commands.give("@p minecraft:map")

        term.setCursorPos(4, 13)
        term.write("Completed build " .. builds.. " of " .. (mapsX * mapsY) .. ".")

        term.setTextColour(colours.lightGrey)
        term.setBackgroundColour(colours.blue)
        term.setCursorPos(5, 15)
        term.write(" Cancel ")
        term.setCursorPos(37, 15)
        term.write(" Continue ")

        while true do
            myEvent = {os.pullEvent("mouse_click")}

            if clickedAt(4, 13, 15) then
                return
            elseif clickedAt(36, 47, 15) then
                break
            end
        end
    end
end

---------------------------------------------
------------         Init        ------------
---------------------------------------------

if not os.getComputerLabel() then os.setComputerLabel("mapArt") end

term.setTextColour(colours.black)
term.setBackgroundColour(colours.brown)

for j = 0, 1 do for i = 1, 3 do
    term.setCursorPos(1, i + (j * (ySize - 3)))
    term.clearLine()
end end

term.setCursorPos(5, 2)
term.write("mapArt")
term.setCursorPos(2, ySize - 1)
term.write("This system is facing "..({"unknown", "north", "south", "west", "east"})[commands.getBlockInfo(commands.getBlockPosition()).metadata]..".")

paintutils.drawPixel(1, 1, colours.blue)
paintutils.drawPixel(2, 1, colours.green)
paintutils.drawPixel(3, 1, colours.yellow)
paintutils.drawPixel(1, 2, colours.grey)
paintutils.drawPixel(2, 2, colours.white)
paintutils.drawPixel(3, 2, colours.lightBlue)
paintutils.drawPixel(1, 3, colours.orange)
paintutils.drawPixel(2, 3, colours.lime)
paintutils.drawPixel(3, 3, colours.red)

-- Build a palette file suitable for the current MC install:
if not fs.exists("mapArt.pal") then
    -- All colours as of MC1.12,
    -- except the first, which is prone to change,
    -- and water, which doesn't work well with staircasing:
    local basePal = {
        {127, 178,  56, "minecraft:grass"},
        {247, 233, 163, "minecraft:sandstone"},
        {199, 199, 199, "minecraft:web"},
        {255,   0,   0, "minecraft:redstone_block"},
        {160, 160, 255, "minecraft:packed_ice"},
        {167, 167, 167, "minecraft:iron_block"},
        {  0, 124,   0, "minecraft:leaves"},
        {255, 255, 255, "minecraft:wool"},
        {164, 168, 184, "minecraft:clay"},
        {151, 109,  77, "minecraft:planks", 3},
        {112, 112, 112, "minecraft:cobblestone"},
        {143, 119,  72, "minecraft:planks"},
        {255, 252, 245, "minecraft:stone", 3},
        {216, 127,  51, "minecraft:planks", 4},
        {178,  76, 216, "minecraft:wool", 2},
        {102, 153, 216, "minecraft:wool", 3},
        {229, 229,  51, "minecraft:wool", 4},
        {127, 204,  25, "minecraft:wool", 5},
        {242, 127, 165, "minecraft:wool", 6},
        { 76,  76,  76, "minecraft:wool", 7},
        {153, 153, 153, "minecraft:wool", 8},
        { 76, 127, 153, "minecraft:wool", 9},
        {127,  63, 178, "minecraft:wool", 10},
        { 51,  76, 178, "minecraft:wool", 11},
        {102,  76,  51, "minecraft:planks", 5},
        {102, 127,  51, "minecraft:wool", 13},
        {153,  51,  51, "minecraft:wool", 14},
        { 25,  25,  25, "minecraft:wool", 15},
        {250, 238,  77, "minecraft:gold_block"},
        { 92, 219, 213, "minecraft:diamond_block"},
        { 74, 128, 255, "minecraft:lapis_block"},
        {  0, 217,  58, "minecraft:emerald_block"},
        {129,  86,  49, "minecraft:planks", 1},
        {112,   2,   0, "minecraft:netherrack"},
        {209, 177, 161, "minecraft:stained_hardened_clay"},
        {159,  82,  36, "minecraft:stained_hardened_clay", 1},
        {149,  87, 108, "minecraft:stained_hardened_clay", 2},
        {112, 108, 138, "minecraft:stained_hardened_clay", 3},
        {186, 133,  36, "minecraft:stained_hardened_clay", 4},
        {103, 117,  53, "minecraft:stained_hardened_clay", 5},
        {160,  77,  78, "minecraft:stained_hardened_clay", 6},
        { 57,  41,  35, "minecraft:stained_hardened_clay", 7},
        {135, 107,  98, "minecraft:stained_hardened_clay", 8},
        { 87,  92,  92, "minecraft:stained_hardened_clay", 9},
        {122,  73,  88, "minecraft:stained_hardened_clay", 10},
        { 76,  62,  92, "minecraft:stained_hardened_clay", 11},
        { 76,  50,  35, "minecraft:stained_hardened_clay", 12},
        { 76,  82,  42, "minecraft:stained_hardened_clay", 13},
        {142,  60,  46, "minecraft:stained_hardened_clay", 14},
        { 37,  22,  16, "minecraft:stained_hardened_clay", 15}
    }

    -- Remove anything we can't setblock:
    for i = #basePal, 1, -1 do
        local this = basePal[i]
        if not this[5] then this[5] = 0 end

        commands.setblock(x, y + 1, z, this[4],this[5])
        local data = commands.getBlockInfo(x, y + 1, z)
        if data.name ~= this[4] or data.metadata ~= this[5] then table.remove(basePal, i) end
    end

    -- If we can't setblock glazed terracotta, also remove regular terracotta (it has no special colour prior to MC1.12):
    commands.setblock(x, y + 1, z, "minecraft:white_glazed_terracotta")
    if basePal[#basePal][4] == "minecraft:stained_hardened_clay" and commands.getBlockInfo(x, y + 1, z).name ~= "minecraft:white_glazed_terracotta" then for i = #basePal - 15, #basePal do basePal[i] = nil end end

    commands.setblock(x, y + 1, z, "minecraft:air")

    -- Triplicate the entries to get the three different shades:
    local len = #basePal
    for i = 1, len do
        local old, new1, new2 = basePal[i], {}, {}

        new1[1], new1[2], new1[3] = math.floor(old[1] * 220 / 255), math.floor(old[2] * 220 / 255), math.floor(old[3] * 220 / 255)
        new2[1], new2[2], new2[3] = math.floor(old[1] * 180 / 255), math.floor(old[2] * 180 / 255), math.floor(old[3] * 180 / 255)
        new1[4], new1[5], new2[4], new2[5] = old[4], old[5], old[4], old[5]

        basePal[i + len], basePal[i + 2 * len] = new1, new2
    end

    basePal[0] = {1000, 1000, 1000, transparent, 0}

    -- Save for future reference:
    local output = fs.open("mapArt.pal", "w")
    output.write(textutils.serialise(basePal))
    output.close()
end

local myLoc = "My location: X: " .. x .. ", Y: " .. y .. ", Z: " .. z
local buildArea = "Build area: X: " .. (x1 - 4) .. " - " .. (x1 + 131).. ", Z: " .. (z1 - 4) .. " - " .. (z1 + 131)

local ready = (x == x1 + 64 and y == 1 and z == z1 + 63)

---------------------------------------------
------------  Main Program Loop  ------------
---------------------------------------------

while true do
    clear(colours.black, colours.lightGrey)

    term.setCursorPos(22, 5)
    term.write("What Do?")

    term.setCursorPos(math.floor((xSize - #myLoc) / 2) + 1, 14)
    term.write(myLoc)
    term.setCursorPos(math.floor((xSize - #buildArea) / 2) + 1, 15)
    term.write(buildArea)

    term.setTextColour(colours.lightGrey)
    term.setBackgroundColour(colours.grey)

    term.setCursorPos(21, 8)
    if ready then
        term.write("  Build   ")
        term.setCursorPos(21, 10)
        term.write("   Fill   ")
    else
        term.write(" Prepare  ")
    end

    term.setCursorPos(21, 12)
    term.write("   Quit   ")

    myEvent = {os.pullEvent()}

    if clickedAt(20, 31, 8) then
        if ready then
            -- Build something.
            local filename = fileBrowser()
            if filename then doBuild(filename) end
        else
            -- Prepare build area.

            -- Safe room:
            commands.execAsync("fill " .. (x1 + 59) .. " 0 " .. (z1 + 59) .. " " .. (x1 + 68) .. " 5 " .. (z1 + 68) .. " minecraft:bedrock")
            commands.execAsync("fill " .. (x1 + 60) .. " 1 " .. (z1 + 60) .. " " .. (x1 + 67) .. " 4 " .. (z1 + 67) .. " minecraft:air")
            commands.execAsync("setblock " .. (x1 + 63) .. " 1 " .. (z1 + 63) .. " minecraft:ender_chest 3")
            commands.execAsync("setblock " .. (x1 + 64) .. " 1 " .. (z1 + 63) .. " minecraft:bedrock")
            commands.execAsync("setblock " .. (x1 + 64) .. " 2 " .. (z1 + 63) .. " minecraft:torch 5")
            commands.execAsync(teleport .. " @p " .. (x1 + 64) .. " 2 " .. (z1 + 65))

            -- Empty out the surrounding chunks:
            for yy = 255, 3, -1 do if yy ~= y then commands.execAsync("fill " .. (x1 - 4) .. " " .. yy .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. yy .. " " .. (z1 + 131) .. " minecraft:air") end end
            commands.execAsync("fill " .. (x1 - 4) .. " 0 " .. (z1 - 4) .. " " .. (x1 + 67) .. " 2 " .. (z1 + 59) .. " minecraft:air")
            commands.execAsync("fill " .. (x1 + 68) .. " 0 " .. (z1 - 4) .. " " .. (x1 + 131) .. " 2 " .. (z1 + 67) .. " minecraft:air")
            commands.execAsync("fill " .. (x1 + 60) .. " 0 " .. (z1 + 68) .. " " .. (x1 + 131) .. " 2 " .. (z1 + 131) .. " minecraft:air")
            commands.execAsync("fill " .. (x1 - 4) .. " 0 " .. (z1 + 60) .. " " .. (x1 + 59) .. " 2 " .. (z1 + 131) .. " minecraft:air")

            -- Teleport pads:
            commands.execAsync("fill " .. (x1 + 60) .. " 1 " .. (z1 + 60) .. " " ..(x1 + 61) .. " 1 " .. (z1 + 61) .. " minecraft:bedrock")
            commands.execAsync("fill " .. (x1 + 66) .. " 1 " .. (z1 + 60) .. " " ..(x1 + 67) .. " 1 " .. (z1 + 61) .. " minecraft:bedrock")
            commands.execAsync("fill " .. (x1 + 60) .. " 1 " .. (z1 + 66) .. " " ..(x1 + 61) .. " 1 " .. (z1 + 67) .. " minecraft:bedrock")
            commands.execAsync("fill " .. (x1 + 66) .. " 1 " .. (z1 + 66) .. " " ..(x1 + 67) .. " 1 " .. (z1 + 67) .. " minecraft:bedrock")
            commands.execAsync("setblock " .. (x1 + 61) .. " 2 " .. (z1 + 61) .. " minecraft:wooden_pressure_plate")
            commands.execAsync("setblock " .. (x1 + 66) .. " 2 " .. (z1 + 61) .. " minecraft:wooden_pressure_plate")
            commands.execAsync("setblock " .. (x1 + 61) .. " 2 " .. (z1 + 66) .. " minecraft:wooden_pressure_plate")
            commands.execAsync("setblock " .. (x1 + 66) .. " 2 " .. (z1 + 66) .. " minecraft:wooden_pressure_plate")
            commands.execAsync("setblock " .. (x1 + 61) .. " 0 " .. (z1 + 61) .. " minecraft:command_block 1 replace {Command:\"" .. teleport .. " @p " .. (x1 - 5) .. " 150 " .. (z1 - 5) .. "\"}")
            commands.execAsync("setblock " .. (x1 + 66) .. " 0 " .. (z1 + 61) .. " minecraft:command_block 1 replace {Command:\"" .. teleport .. " @p " .. (x1 + 132) .. " 150 " .. (z1 - 5) .. "\"}")
            commands.execAsync("setblock " .. (x1 + 61) .. " 0 " .. (z1 + 66) .. " minecraft:command_block 1 replace {Command:\"" .. teleport .. " @p " .. (x1 - 5) .. " 150 " .. (z1 + 132) .. "\"}")
            commands.execAsync("setblock " .. (x1 + 66) .. " 0 " .. (z1 + 66) .. " minecraft:command_block 1 replace {Command:\"" .. teleport .. " @p " .. (x1 + 132) .. " 150 " .. (z1 + 132) .. "\"}")
            commands.execAsync("setblock " .. (x1 + 60) .. " 2 " .. (z1 + 60) .. " minecraft:standing_sign 14 replace {Text2:\"{\\\"text\\\":\\\"North\\\"}\",Text3:\"{\\\"text\\\":\\\"West\\\"}\"}")
            commands.execAsync("setblock " .. (x1 + 67) .. " 2 " .. (z1 + 60) .. " minecraft:standing_sign 2 replace {Text2:\"{\\\"text\\\":\\\"North\\\"}\",Text3:\"{\\\"text\\\":\\\"East\\\"}\"}")
            commands.execAsync("setblock " .. (x1 + 60) .. " 2 " .. (z1 + 67) .. " minecraft:standing_sign 10 replace {Text2:\"{\\\"text\\\":\\\"South\\\"}\",Text3:\"{\\\"text\\\":\\\"West\\\"}\"}")
            commands.execAsync("setblock " .. (x1 + 67) .. " 2 " .. (z1 + 67) .. " minecraft:standing_sign 6 replace {Text2:\"{\\\"text\\\":\\\"South\\\"}\",Text3:\"{\\\"text\\\":\\\"East\\\"}\"}")

            -- Swap computers (this will fail horribly if the original computer was already near bedrock):
            commands.execAsync("setblock " .. (x1 + 64) .. " 1 " .. (z1 + 63) .. " computercraft:command_computer 3 replace {computerID:" .. os.getComputerID() .. ",x:" .. (x1 + 64) .. ",y:1,z:" .. (z1 + 63) .. ",id:\"computercraft : command_computer\",label:\"" .. os.getComputerLabel() .. "\",on:0b}")
            commands.execAsync("fill " .. (x1 - 4) .. " " .. y .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. y .. " " .. (z1 + 131) .. " minecraft:air")
        end
    elseif clickedAt(20, 31, 10) and ready then
        -- Fill build area back in with featureless terrain.
        clear(colours.black, colours.lightGrey)
        term.setCursorPos(math.floor((xSize - 10) / 2) + 1, 5)
        term.write("Filling...")
        sleep(0)

        for y = 63, 255 do commands.execAsync("fill " .. (x1 - 4) .. " " .. y .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. y .. " " .. (z1 + 131) .. " minecraft:air") end
        commands.execAsync("fill " .. (x1 - 4) .. " 62 " .. (z1 - 4) .. " " .. (x1 + 131) .. " 62 " .. (z1 + 131) .. " minecraft:grass")
        commands.execAsync("fill " .. (x1 - 4) .. " 0 " .. (z1 - 4) .. " " .. (x1 + 131) .. " 0 " .. (z1 + 131) .. " minecraft:bedrock")
        for y = 56, 61 do commands.execAsync("fill " .. (x1 - 4) .. " " .. y .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. y .. " " .. (z1 + 131) .. " minecraft:dirt") end
        for y = 55, 3, -1 do commands.execAsync("fill " .. (x1 - 4) .. " " .. y .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. y .. " " .. (z1 + 131) .. " minecraft:stone") end

        commands.execAsync("setblock " .. (x1 + 64) .. " 63 " .. (z1 + 63) .. " computercraft:command_computer 3 replace {computerID:" .. os.getComputerID() .. ",x:" .. (x1 + 64) .. ",y:63,z:" .. (z1 + 63) .. ",id:\"computercraft : command_computer\",label:\"" .. os.getComputerLabel() .. "\",on:0b}")
        commands.execAsync(teleport .. " @p " .. (x1 + 64) .. " 64 " .. (z1 + 65))
        for y = 2, 1, -1 do commands.execAsync("fill " .. (x1 - 4) .. " " .. y .. " " .. (z1 - 4) .. " " .. (x1 + 131) .. " " .. y .. " " .. (z1 + 131) .. " minecraft:stone") end
    elseif clickedAt(20, 31, 12) or pressedKey(keys.q, keys.x) then
        -- Exit.
        if myEvent[1] == "key" then os.pullEvent("char") end
        break
    end
end

---------------------------------------------
------------         Exit        ------------
---------------------------------------------

term.setTextColour(colours.white)
term.setBackgroundColour(colours.black)
term.clear()
term.setCursorPos(1, 1)
print("Thanks for using mapArt!\n")
shell.setDir(startDir)