Unrolled line algorithm

declare sub nLine( byref x1 as integer, byref y1 as integer, byref x2 as integer, byref y2 as integer, byref c as uinteger, byref lthick as integer = 0  )

screenres 640,480,32





do

    screenlock
    nLine int(rnd*640),int(rnd*480),int(rnd*640),int(rnd*480), rgb(rnd*256,rnd*256,rnd*256), 1
    screenunlock

    sleep 3,1

loop until inkey$=chr$(27)

sleep








sub nLine( byref x1 as integer, byref y1 as integer, byref x2 as integer, byref y2 as integer, byref c as uinteger, byref lthick as integer = 0  )

    dim as integer Xdif = x2 - x1
    dim as integer Ydif = y2 - y1
    dim as integer xit, yit, tempx, tempy

    if Xdif < 0 then
        Xdif = -Xdif
    end if

    if Ydif < 0 then
        Ydif = -Ydif
    end if

    if Xdif >= Ydif then
        if x2 < x1 then
            swap x2, x1
            swap y2, y1
        end if

        if y2 < y1 then
            Xit = -1
        else
            Xit = 1
        end if

        TempY = y1

        for TempX = x1 to x2
            'pset(TempX, TempY), c
            'line(tempx-lthick,tempy-lthick)-(tempx+lthick,tempy+lthick),c,bf
            circle(tempx, tempY), lThick, c,,,,f
            Yit = Yit - Ydif

            if Yit < 0 then
                Yit = Yit + Xdif
                TempY = TempY + Xit
            end if
        next

    else

        if y2 < y1 then
            swap x2, x1
            swap y2, y1
        end if

        if x2 < x1 then
            Xit = -1
        else
            Xit = 1
        end if

        TempX = x1

        for TempY = y1 to y2
            'pset(TempX, TempY), c
            'line(tempx-lthick,tempy-lthick)-(tempx+lthick,tempy+lthick),c,bf
            circle(tempx, tempY), lThick, c,,,,f
            Yit = Yit - Xdif

            if Yit < 0 then
                Yit = Yit + Ydif
                TempX = TempX + Xit
            end if
        next

    end if

end sub