Starfield Lateral

local w, h = term.getSize()
local stars = {}
local velocity = 1
local tArgs = {...}
local compnum = tonumber(tArgs[1])
local sendnum = compnum + 1
if sendnum == 5 then sendnum = 1 end

Star = {
x = 0,
y = 0
}

function Star:new(x, y)
    local class = {x = x, y = y}
    setmetatable(class, self)
    self.__index = self
    return class
end

function generateStars()
    local generatelist = {}
    for i = 1, 30 do
        local x = nil
        local y = nil
        local success = false
        while not success do
            x = math.random(1, w)
            y = math.random(1, h)
            success = true
            for i, v in pairs(generatelist) do
                if i == x and v == y then
                    success = false
                end
            end
        end
        stars[i] = Star:new(x, y)
        generatelist[#generatelist + 1] = {x, y}
    end
end

term.setBackgroundColor(colors.black)
term.clear()
generateStars()
local deleteprev = false
while true do
    if velocity < 0 then
        sendnum = sendnum - 2
    elseif velocity > 0 then
        sendnum = sendnum + 2
    end
    if sendnum < 0 then sendnum = sendnum + 4 end
    if sendnum > 4 then sendnum = sendnum - 4 end
    local newstar = nil
    newstar = {rednet.receive(.05)}
    if newstar and newstar[3] == tostring(compnum) then
        stars[#stars + 1] = Star:new(w, tonumber(newstar[2]))
    elseif newstar and newstar[2] == "velocity +" then
        velocity = velocity + 1
    elseif newstar and newstar[2] == "velocity -" then
        velocity = velocity - 1
    end
    if velocity > 3 then velocity = 3 end
    if velocity < -3 then velocity = -3 end
    for i, _ in pairs(stars) do
        if stars[i] ~= false then
            local star = stars[i]
            if (star.x < 1 and velocity > 0) or (star.x > w and velocity < 0) then
                term.setBackgroundColor(colors.black)
                    term.setCursorPos(1, star.y)
                    term.write("  ")
                rednet.broadcast(tostring(star.y), tostring(sendnum))
                stars[i] = false
                else
                term.setBackgroundColor(colors.black)
                    term.setCursorPos(star.x + velocity, star.y)
                    term.write(" ")
                    term.setCursorPos(star.x, star.y)
                term.setBackgroundColor(colors.white)
                    term.write("*")
                    star.x = star.x - velocity
                stars[i] = star
            end
        end
    end
    --[[local delList = {}
    for i, _ in pairs(stars) do   --note: this way is actually more efficient, but in actual use, it doesn't change
        if not stars[i] then  --enough to make the extra lag worth it
            delList[#delList + 1] = i
        end
    end
    for i, v in pairs(delList) do
        table.remove(stars, v - i + 1)
    end]]--
    for i = 1, #stars do
        if stars[i] ~= nil and stars[i] == false then
            table.remove(stars, i)
        end
    end
end