Basic Bresenham circle implementation in Lua

bresenham_circle.lua

# Ported from https://www.daniweb.com/programming/software-development/threads/321181/python-bresenham-circle-arc-algorithm

-- Bresenham circle
function circle(radius)
    local pixels = {}
    local switch = 3 - (2 * radius)
    local x = 0
    local y = radius
    while x <= y do
        table.insert(pixels, {x, -y})
        table.insert(pixels, {y, -x})
        table.insert(pixels, {y, x})
        table.insert(pixels, {x, y})
        table.insert(pixels, {-x, y})
        table.insert(pixels, {-y, x})
        table.insert(pixels, {-y, -x})
        table.insert(pixels, {-x, -y})
        if switch < 0 then
            switch = switch + (4 * x) + 6
        else
            switch = switch + (4 * (x - y)) + 10
            y = y - 1
        end
        x = x + 1
    end
    return pixels
end