<proc border
    Draw.FillBox (600, 450, 550, 451, black)
    Draw.FillBox (0, 50, 50, 51, black)
        delay (1000)
        cls
    Draw.FillBox (600, 450, 500, 451, black)
    Draw.FillBox (0, 50, 100, 51, black)
        delay (1000)
        cls
    Draw.FillBox (600, 450, 450, 451, black)
    Draw.FillBox (0, 50, 150, 51, black)
        delay (1000)
        cls
    Draw.FillBox (600, 450, 400, 451, black)
    Draw.FillBox (0, 50, 200, 51, black)
        delay (1000)
        cls
    Draw.FillBox (600, 450, 350, 451, black)
    Draw.FillBox (0, 50, 250, 51, black)
        delay (1000)
        cls
    Draw.FillBox (600, 450, 300, 451, black)
    Draw.FillBox (0, 50, 300, 51, black)
end border>

for i: 0 .. 100
   drawFrame(i)
   sleep(50)
end for

% stops flickering; use with View.Update
setscreen ("offscreenonly")

% this is what i use to draw the animated circle border
proc animate_circle_border
        (ox, oy, rad,
        start_color, end_color, color_span, % these are the paramters i use so i can customize
        roughness, thickness, tick : int)   % the output without changing the function
    for i : 0 .. 360 by roughness % this is my counter.  it lets me repeat something while
                                  % keeping track of how much ive done thus far.  by x
                                  % just tells it to skip every x numbers
                                 
        % this is just circular math stuff dont worry about it
        var x1 := round (sind (i + tick) * rad)
        var y1 := round (cosd (i + tick) * rad)
        var x2 := round (sind (i + tick + roughness) * rad)
        var y2 := round (cosd (i + tick + roughness) * rad)
                               % #! im adding tick here because it
                               % lets me make my animation look different each time
                               % i call this draw function... think of it as the frame
                               % counter in a movie
       
        % picking a color
        var c := start_color + ((i div roughness) div color_span)
        if (c > end_color) then
            c := end_color
        end if

        % draw my shape
        Draw.ThickLine (ox + x1, oy + y1, ox + x2, oy + y2, thickness, c)
    end for
end animate_circle_border

% this keeps track of my animation progress i use this in my drawing
% function to make it draw differently each call (illusion of motion)
var tick := 0

% this is my drawing loop
loop
    % clear the screen
    cls
   
    % incriment my progress; dont worry about this - 15 mod 360 stuff thats
    % just how i want my progress to be for the math to work in my drawing function
    % you would be perfectly fine increasing/decreasing however you wish
    tick := (tick - 15) mod 360
   
    % draw my frame, note im passing tick to it... this is so in my function i can
    % let it draw differently (see #!)
    animate_circle_border (maxx div 2, maxy div 2, 100, 21, 31, 15, 1, 3, tick)
   
    % update the screen
    View.Update

    % delay for a while (so it doesn't all happen as fast as turing can draw)
    % im usign delaysincelast here because if the animation takes longer to draw
    % i want to delay less (so it looks like its moving at a uniform speed)
    Time.DelaySinceLast (30)
end loop