triangle.ps

%!
%% Triangle of codes

% Define a simple procedure to show a piece of text at a given position
/showat
{
	newpath
    moveto
    show
	closepath
} bind def

% Move the origin slightly.
10 10 translate
5 5 scale

/Courier findfont

% Apply a matrix to give the font an 80% aspect ratio
[0.4 0 0 0.5 0 0]  makefont

% Make it the current font
setfont

% The 22 valid chars
/ALPHABASE22 (ABCDFGHJKLMNPQRSTVWXYZ) def

% Dummy TLA to be overwritten
/code (***) def

% Set the odometer to 000
/units 0 def
/tens 0 def
/huns 0 def


% Our infections loop from 0 to 99 in increments of 1.
0 1 99 
{ 
    /infections exch def

    % Deaths loop from 0 to {number of infections} in increments of 1.
    0 1 infections
    { 
        /deaths exch def

        code 2 ALPHABASE22 units get put
        code 1 ALPHABASE22 tens get  put
        code 0 ALPHABASE22 huns get  put

        code

        % Calculate the coordinates x = deaths, y = 99-infections …
        % … and put them on the stack

        deaths
        99 infections sub

        % plot the code
        showat

        % roll the odometer on

        units 1 add dup
        22 ge
        {
            tens 1 add dup
            22 ge
            {
                huns 1 add
                /huns def
                pop
                0
            } if

            /tens exch def
            pop
            0
        } if
        /units exch def

    } for
} for 


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