Lua (ROBLOX) drawing script

player=game.Players.LocalPlayer
    mouse=player:GetMouse()
size=UDim2.new(0,50,0,50)
active=false
function createpixel(x,y)
    local pixel = Instance.new('Frame')
        pixel.Size=size
        pixel.Position=UDim2.new(0,x-(pixel.Size.X.Offset/2),0,y-(pixel.Size.Y.Offset/2))
        pixel.Parent=script.Parent
        pixel.BackgroundColor3=BrickColor.new('Cyan').Color
        pixel.BorderSizePixel = 0
end

mouse.Button1Down:connect(function()
    active=true
    repeat wait()   createpixel(mouse.X,mouse.Y) until active==false
end)

mouse.Button1Up:connect(function()
    active = false
end)