TerrariLua V2

local sFile = fs.open("world", "w")
local chunk = 0
local termW, termH = term.getSize()
local midW, midH = math.floor(termW/2), math.floor(termH/2)
local xPos, yPos = 0, 51
local pDir = ">"
local blockinfo = {
["bedrock"] = 128,
["stone"] = 256,
["dirt"] = 4096,
["grass"] = 32,
["air"] = 32768
}
world = nil
local blocks = {}
blocks[0] = "bedrock"
blocks[1] = "bedrock"
for i = 2, 24 do
    blocks[i] = "stone"
end
for i = 25, 40 do
    blocks[i] = "dirt"
end
for i = 41, 49 do
    blocks[i] = "grass"
end
blocks[50] = "air"

function generateWorld(filename)
    local sFile = fs.open(filename, "w")
    for x = -midW - 3, midW + 3 do
        sFile.writeLine("  [" .. tostring(x) .. "] = {")
        for y = 1, 50 do
            sFile.writeLine("    [" .. tostring(y) .. "] = \"" .. tostring(blocks[math.random(y/1.2, y)]) .. "\",")
        end
        for y = 51, 100 do
            sFile.write("    [" .. tostring(y) .. "] = \"air\"")
            if y == 100 then
                sFile.writeLine("")
            else
                sFile.writeLine(",")
            end
        end
        if x == midW + 3 then
            sFile.writeLine("  }")
        else
            sFile.writeLine("  },")
        end
    end
    sFile.close()
end

function displayWorld()
    term.setBackgroundColor(colors.black)
    term.clear()
    term.setCursorPos(midW + 1, midH + 1)
    term.setBackgroundColor(colors.lightBlue)
    term.write(pDir)
    for x = xPos - midW, xPos + midW do
        for y = (yPos > 100 - midH) and 100 or yPos + midH, (yPos <= midH) and 1 or yPos - midH, -1 do
            if world[x][y] ~= "air" then
                term.setCursorPos(xPos + midW - x + 1, midH + yPos - y + 1)
                term.setBackgroundColor(blockinfo[world[x][y]])
                term.write(" ")
            end
        end
    end
end

function loadWorld(filename)
        world = nil
        local lFile = fs.open(filename, "r")
        loadstring("world = {\n" .. lFile.readAll() .. "\n}")()
        lFile.close()
end

function updateWorld()
    if not world[xPos - midW - 3] or not world[xPos + midW + 3] then
        if not world[xPos - midW - 3] then
            world[xPos - midW - 3] = {}
            for y = 1, 50 do
                world[xPos - midW - 3][y] = tostring(blocks[math.random(y/1.2, y)])
            end
            for y = 51, 100 do
                world[xPos - midW - 3][y] = "air"
            end
        elseif not world[xPos + midW + 3] then
            world[xPos + midW + 3] = {}
            for y = 1, 50 do
                world[xPos + midW + 3][y] = tostring(blocks[math.random(y/1.2, y)])
            end
            for y = 51, 100 do
                world[xPos + midW + 3][y] = "air"
            end
        end
    end
end

function saveWorld(filename)
    local sFile = fs.open(filename, "w")
    local worldlen = 0
    local worldmid = nil
    for i, v in pairs(world) do
        worldlen = worldlen + 1
        if i == 0 then
            worldmid = worldlen
        end
    end
    for x = -(worldlen - worldmid), worldmid - 1 do
    sFile.write("  [" .. tostring(x) .. "] = {")
                for y = 1, 100 do
                        sFile.write("\"" .. world[x][y] .. "\"")
                        if y == 100 and x == worldmid - 1 then
                                sFile.writeLine("}")
                        elseif y == 100 then
                            sFile.writeLine("},")
            else
                                sFile.write(", ")
                        end
                end
        sFile.flush()
    end
    sFile.close()
end

term.setBackgroundColor(colors.black)
term.clear()
term.setCursorPos(midW - 4, 2)
term.write("TerrariLua")
term.setCursorPos(midW - 5, 8)
term.write("Start  Game")
term.setCursorPos(midW - 4, 10)
term.write("Exit Game")
term.setBackgroundColor(colors.blue)
while true do
    local events = {os.pullEvent()}
    if events[1] == "mouse_click" and events[2] == 1 then
        if events[3] >= midW - 5 and events[3] <= midW + 5 and events[4] == 8 then
            term.setCursorPos(midW - 5, 8)
            term.write("Start  Game")
            sleep(.2)
            break
        end
        if events[3] >= midW - 4 and events[3] <= midW + 4 and events[4] == 10 then
            term.setCursorPos(midW - 4, 10)
            term.write("Exit Game")
            sleep(.2)
            os.exit()
        end
    end
end
term.setBackgroundColor(colors.black)
term.clear()
term.setCursorPos(midW - 4, 2)
term.write("Start Menu")
term.setCursorPos(midW - 4, 8)
term.write("New  Game")
term.setCursorPos(midW - 4, 10)
term.write("Load Game")
term.setBackgroundColor(colors.blue)
local startUp = nil
while true do
    local events = {os.pullEvent()}
    if events[1] == "mouse_click" and events[2] == 1 then
        if events[3] >= midW - 4 and events[3] <= midW + 4 and events[4] == 8 then
            term.setCursorPos(midW - 4, 8)
            term.write("New  Game")
            startUp = "new"
            sleep(.2)
            break
        end
        if events[3] >= midW - 4 and events[3] <= midW + 4 and events[4] == 10 then
            term.setCursorPos(midW - 4, 10)
            term.write("Load Game")
            startUp = "load"
            sleep(.2)
            break
        end
    end
end
term.setBackgroundColor(colors.black)
term.clear()
term.setCursorPos(1, 1)
term.write("Input World Name: ")
local filename = nil
if startUp == "new" then
    filename = tostring(read())
    generateWorld(filename)
    loadWorld(filename)
elseif startUp == "load" then
    filename = tostring(read())
    loadWorld(filename)
end
while true do
    updateWorld()
    displayWorld()
    term.setCursorPos(1, 1)
    term.write(tostring(xPos) .. "," .. tostring(yPos))
    sleep(.05)
    local events = {os.pullEvent()}
    if events[1] == "key" then
        if events[2] == 200 then --up
            pDir = "^"
            if world[xPos][yPos + 1] == "air" then
                yPos = yPos + 1
            end
        elseif events[2] == 205 then --right
            pDir = ">"
            if world[xPos - 1][yPos] == "air" then
                xPos = xPos - 1
            end
        elseif events[2] == 208 then --down
            pDir = "v"
            if world[xPos][yPos - 1] == "air" then
                yPos = yPos - 1
            end
        elseif events[2] == 203 then --left
            pDir = "<"
            if world[xPos + 1][yPos] == "air" then
                xPos = xPos + 1
            end
        end
        if events[2] == 17 then
            pDir = "^"
        elseif events[2] == 30 then
            pDir = "<"
        elseif events[2] == 31 then
            pDir = "v"
        elseif events[2] == 32 then
            pDir = ">"
        end
        if events[2] == 45 then
            local changeB = "air"
            local oTemp = fs.open("temp", "w")
            local changeX, changeY = nil, nil
            local ready = false
            if pDir == "^" then
                changeX, changeY = xPos, yPos + 1
            elseif pDir == ">" then
                changeX, changeY = xPos - 1, yPos
            elseif pDir == "v" then
                changeX, changeY = xPos, yPos - 1
            elseif pDir == "<" then
                changeX, changeY = xPos + 1, yPos
            end
            if world[changeX][changeY] ~= "bedrock" then
                world[changeX][changeY] = "air"
            end
        end
        if events[2] == 46 then
            local changeB = "stone"
            local oTemp = fs.open("temp", "w")
            local changeX, changeY = nil, nil
            local ready = false
            if pDir == "^" then
                changeX, changeY = xPos, yPos + 1
            elseif pDir == ">" then
                changeX, changeY = xPos - 1, yPos
            elseif pDir == "v" then
                changeX, changeY = xPos, yPos - 1
            elseif pDir == "<" then
                changeX, changeY = xPos + 1, yPos
            end
            if world[changeX][changeY] == "air" then
                world[changeX][changeY] = "stone"
            end
        end
        if events[2] == 29 then
            saveWorld(filename)
        end
    end
end