digCircle v1.0

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-- Made by nDoorn --
--------------------
--- Version 1.0 ---
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-- How to use this program? --
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-- Place an Fuel chest in slot 16
-- Place an Item chest in slot 15
-- Set the settings
-- Start the program!

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---- SETTINGS ----
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local radius        = 5
local depth         = 5
local quarters      = 1
local minFuelLevel  = 600

--------------------------------------------
---------------- FUNCTIONS -----------------
--------------------------------------------
function round(num) return math.floor(num + 0.5) end

function digCircle(grid)
local X = 0
local Y = 0
local DigDepth = depth - 2
local GridValue = 0

checkFuel()

    while true do
        for i=1, quarters, 1 do
            while true do
                if (grid[X][Y + 1] == 1) then
                    tForwardDig(1)
                    Y = Y + 1
                else
                    tBack(Y)
                    Y = 0

                    depositItems()
                    checkFuel()

                    if (grid[X+1][Y] == 1) then
                        turtle.turnRight()
                        tForwardDig(1)
                        X = X + 1
                        turtle.turnLeft()
                    else
                        turtle.turnRight()
                        tBack(X)
                        X = 0
                        break
                    end
                end
            end
        end

        for i=1, quarters, 1 do
            turtle.turnLeft()
        end

        if (DigDepth == 0) then
            break
        end

        if (DigDepth == 1) then
            turtle.digDown()
            turtle.down()
            turtle.digDown()
            DigDepth = DigDepth - 1
        end

        if (DigDepth >= 2) then
            turtle.digDown()
            turtle.down()
            turtle.digDown()
            turtle.down()
            turtle.digDown()
            DigDepth = DigDepth - 2
        end

        depositItems()

    end

    print("-----------------------------")
    print("-- Yay, i am done. Phew :) --")
    print("-----------------------------")
end

function tForwardDig(steps)
    for k=1, steps, 1 do
        turtle.dig()
        turtle.forward()
        turtle.digDown()
    end
end

function tLeft(steps)
    for k=1, steps, 1 do
        turtle.turnLeft()
    end
end

function tRight(steps)
    for k=1, steps, 1 do
        turtle.turnRight()
    end
end

function tBack(steps)
    for k=1, steps, 1 do
        turtle.back()
    end
end

function checkFuel()
    local fuel = turtle.getFuelLevel()
    local refuelItems = 0
    if fuel < minFuelLevel then
        turtle.select(16)                       -- Select the Fuel chest
        turtle.placeUp()                        -- Place the fuel chest
        turtle.suckUp()                         -- Get some fuel from the chest
        refuelItems = turtle.getItemCount(16)   -- Get the number of fuel items
        turtle.refuel(refuelItems)              -- Refuel the turtle
        turtle.digUp()                          -- Pickup the chest again
    end
end

function depositItems()
    turtle.select(15)                           -- Select the item chest slot
    turtle.placeUp()                            -- Place the item chest
    for i=1, 14, 1 do                           -- Go through all the slots of the turtle
        turtle.select(i)                        -- Select slot 1 - 14
        if (turtle.getItemCount ~= 0) then      -- check if there is an item there
            turtle.dropUp()                     -- If there is, put it in the chest
        end
    end
    turtle.select(15)                           -- Select slot 15
    turtle.digUp()                              -- Pick up the chest
end

--------------------------------------------
------------------- CODE -------------------
--------------------------------------------
term.clear()

-- Create an array
local grid = {}

for x=0, radius, 1 do
    grid[x] = {}
    for y=0, radius, 1 do
        grid[x][y] = 0
    end
end

local original = {}

term.clear()
term.setCursorPos(1,1)

print("Circle radius is : ", radius)
print("Circle depth is  : ", depth)
print("Turtle fuel level: ", turtle.getFuelLevel())
print("")
print("Calculating the grid")
-- Calculate the step values
for i=0, radius - 1, 1 do --for i=0, radius - 1, 1 do
    local buffer    = 0

    buffer = math.sqrt(math.pow(radius, 2) - math.pow(i, 2))
    buffer = round(buffer) - 1

    for j=i, buffer, 1 do
        grid[i][j] = 1
    end

    for j=i, buffer, 1 do
        grid[j][i] = 1
    end
end

print ("Starting with digging")
print ("")
digCircle(grid)