sdig

-- NAME: SDIG
-- usage SDIG <B> <Z> <S>
-- digs a 1x3 tunnel of Z length in an S-shaped pattern, with B number of branches, with S spaces between each branch
-- digs its way down main trunk to point of origin

local tArgs = {...}
local BTarget = tonumber(tArgs[1])
local ZTarget = tonumber(tArgs[2])
local STarget = tonumber(tArgs[3])
local BPass = 0

-- Dig a 1x3 chunk
function ZDig()
    while (turtle.detect()) do
        turtle.dig()
    end
    turtle.forward()
    turtle.digUp()
    turtle.digDown()
end


-- Dig the branch of z length
function Branch()
    for i=1, ZTarget do
        ZDig()
        if i % 8 == 0 then -- places torches every 8 spaces
            turtle.select(16)
            turtle.placeDown()
        end
    end
    BPass = BPass + 1 -- when the branch has been completed, increment the BPass
end


-- Turn the correct direction at end of branch
function Orient()
    if BPass % 2 == 0 then
        turtle.turnLeft()
    else
        turtle.turnRight()
    end
end


-- Dig to start of next branch (STarget spaces away)
function GotoBranchStart()
    for i=1, (STarget+1) do
        ZDig()
    end
    Orient() -- point turtle in right direction
end


-- Return from location on main branch back to Origin
function GotoOrigin()
    if BPass > 1 then
        for i=1, (BPass-1)*(1+STarget) do
            while (turtle.detect()) do
                turtle.dig()
            end
            turtle.forward()
            turtle.digUp()
            turtle.digDown()
        end
    end
end

-- PROGRAM



Branch()
while BPass < BTarget do
    Orient()
    GotoBranchStart()
    Branch()
end
if BPass % 2 ~= 0 then
    turtle.turnRight()
    turtle.turnRight()
    for i=1, ZTarget do
        turtle.forward()
    end -- now back at main branch
end
turtle.turnRight()
GotoOrigin()