%telspb%
% generate characters filled with tiny dots
input telmode;
%mode:=proof;
%boolean testing; testing := true;
font_size 72pt#;
slant:=0;
pen_width#:=2.5pt#;
% Following code(with minor modifications) is taken from the article,  
% The ABC's of Special Effects by Georgia K. M. Tobin,
% that appeared in TUGboat, Volume 9(1988), No. 1
vardef special_effects=
% creates characters filled with tiny dots.
    cullit;
    picture Normalchar;
         Normalchar:=currentpicture;
    clearit;
% Depending on the output device, pen size  (0.5pt) may need to be
% changed.
    pickup pencircle scaled 0.5pt; 
    filldraw (0,-d)--(w,-d)--
         (w,h)--(0,h)--cycle;
    picture Blackbox;
         Blackbox:=currentpicture;
    picture Reversevideo;
         Reversevideo:=Blackbox-Normalchar;
    clearit;
% Depending on the output device,stepsizes(u/4 and uh/4) may need to be
% changed.
    for g=0 step u/4 until w:
      for f=-d step uh/4 until h:
         draw(g,f);
      endfor;
    endfor;
    picture Dottedoverlay;
         Dottedoverlay:=currentpicture;
    currentpicture:=Dottedoverlay-Reversevideo;
enddef;
input telparam;  
%%