%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%    Loggates.mf --- special characters for drawing digital
%    electronic circuits with logical gates.
%
%    Version history:
%    -  "milstd" font by Rick Simpson, font for logical gates
%       as in MIL-STD 806.
%       (published in UKTeX 1988, issue 30 (23 Sept. 1988).)
%    -  Extended version, 30 March 1992, by Nico Verwer,
%       now called loggates.mf. Added XOR, NXOR and OR-input
%       lines, supported in loggates.sty.
%
%    To create the "loggates" font, use the command:
%       makefont loggates
%    or:  
%       mf '\mode=localfont; mag=magstepX ; input' loggates.mf
%    for X = 0, 0.5, 1, 2, 3, 4, 5.
%
%    To use the characters in a PLAIN TeX document:
%       \font\loggates=loggates         % define the font
%            . . .
%       {\loggates\char0}               % typeset the character
%
%    To use the characters in a LaTeX document:
%        \newfont{\loggates}{loggates}   % define the font
%             . . .
%        {\loggates\char0}               % typeset the character
%
%    The file loggates.sty contains definitions that make this 
%    font easy to use.
%

mode_setup;
font_identifier "LOGGATES";
font_size 10pt#;
gatew = 1.2pt;
linew = 0.4pt;

picture pic;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Slanting line at 45-degree angle for marking
%       busses in logic diagrams.

slwd#:=7pt#;
define_pixels(slwd);

beginchar(0,slwd#,slwd#,0);  "Slanted line for buss widths";

x1 = 0;
y1 = 0;

x2 = slwd;
y2 = slwd;

pickup pencircle scaled gatew;
draw z1--z2;

labels (1,2);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       AND gate, facing to the right
%

gateunit# := 6pt#;

gatea# := 2   * gateunit#;
gateb# := 4   * gateunit#;
gatec# := 2.5 * gateunit#;
gated# := 2   * gateunit#;

define_pixels(gatea,gateb,gatec,gated);

w_and# := gatec#+gated#;
h_and# := gateb#;
define_pixels(w_and,h_and);

beginchar(1,w_and#,h_and#,0);  "AND gate, right";

x1 = x2 = 0;
x3 = x5 = gatec;
x4 = gatec + gated;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = gatea;

pickup pencircle scaled gatew;
draw z1--z2--z3{right}..z4..{left}z5--z1;

pic := currentpicture;

labels (range 1 thru 5);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       AND gate, facing down
%

beginchar(2,h_and#,w_and#,0);  "AND gate, down";

currentpicture := pic rotated 270 shifted (0,w_and);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       AND gate, facing to the left
%

beginchar(3,w_and#,h_and#,0);  "AND gate, right";

currentpicture := pic rotated 180 shifted(w_and,h_and);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       AND gate, facing up
%

beginchar(4,h_and#,w_and#,0);  "AND gate, up";

currentpicture := pic rotated 90 shifted(h_and,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NAND gate, facing to the right
%

gatee# := gateunit#;

define_pixels(gatee);

w_nand# := gatec#+gated#+gatee#;
h_nand# := gateb#;
define_pixels(w_nand,h_nand);

beginchar(5,w_nand#,h_nand#,0);  "NAND gate, right";

x1 = x2 = 0;
x3 = x5 = gatec;
x4 = gatec + gated;
x6 = x4 + gatee/2;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = gatea;
y6 = y4;

pickup pencircle scaled gatew;
draw z1--z2--z3{right}..z4..{left}z5--z1;
draw fullcircle scaled gatee shifted(z6);

pic := currentpicture;

labels (range 1 thru 6);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NAND gate, facing down
%

beginchar(6,h_nand#,w_nand#,0);  "NAND gate, down";

currentpicture := pic rotated 270 shifted (0,w_nand);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NAND gate, facing to the left
%

beginchar(7,w_nand#,h_nand#,0);  "NAND gate, left";

currentpicture := pic rotated 180 shifted(w_nand,h_nand);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NAND gate, facing up
%

beginchar(8,h_nand#,w_nand#,0);  "NAND gate, up";

currentpicture := pic rotated 90 shifted(h_nand,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       OR gate, facing to the right
%

gatef# := .75 * gateunit#;
gateg# := 1.5 * gateunit#;
gateh# := 3   * gateunit#;

define_pixels(gatef,gateg,gateh);

w_or# := gateg#+gateh#;
h_or# := gateb#;
define_pixels(w_or,h_or);

beginchar(9,w_or#,h_or#,0);  "OR gate, right";

x1 = x2 = 0;
x3 = x5 = gateg;
x4 = gateg + gateh;
x6 = gatef;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = y6 = gatea;

pickup pencircle scaled gatew;
draw z1..z6..z2;
draw z2--z3;
draw z3{right}..{(1,-2)}z4;
draw z4{-1,-2}..z5{left};
draw z5--z1;

pic := currentpicture;

labels (range 1 thru 6);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       OR gate, facing down
%

beginchar(10,h_or#,w_or#,0);  "OR gate, down";

currentpicture := pic rotated 270 shifted (0,w_or);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       OR gate, facing to the left
%

beginchar(11,w_or#,h_or#,0);  "OR gate, left";

currentpicture := pic rotated 180 shifted(w_or,h_or);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       OR gate, facing up
%

beginchar(12,h_or#,w_or#,0);  "OR gate, up";

currentpicture := pic rotated 90 shifted(h_or,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NOR gate, facing to the right
%

w_nor# := gateg#+gateh#+gatee#;
h_nor# := gateb#;
define_pixels(w_nor,h_nor);

beginchar(13,w_nor#,h_nor#,0);  "NOR gate, right";

x1 = x2 = 0;
x3 = x5 = gateg;
x4 = gateg + gateh;
x6 = gatef;
x7 = x4 + gatee/2;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = y6 = gatea;
y7 = y4;

pickup pencircle scaled gatew;
draw z1..z6..z2;
draw z2--z3;
draw z3{right}..{(1,-2)}z4;
draw z4{-1,-2}..z5{left};
draw z5--z1;
draw fullcircle scaled gatee shifted (z7);

pic := currentpicture;

labels (range 1 thru 7);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NOR gate, facing down
%

beginchar(14,h_nor#,w_nor#,0);  "NOR gate, down";

currentpicture := pic rotated 270 shifted (0,w_nor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NOR gate, facing to the left
%

beginchar(15,w_nor#,h_nor#,0);  "NOR gate, left";

currentpicture := pic rotated 180 shifted(w_nor,h_nor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NOR gate, facing up
%

beginchar(16,h_nor#,w_nor#,0);  "NOR gate, up";

currentpicture := pic rotated 90 shifted(h_nor,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Buffer, facing to the right
%

gatei# := 3    * gateunit#;
gatej# := .866 * gatei#;
gatek# := 1.5  * gateunit#;

define_pixels(gatei,gatej,gatek);

w_buf# := gatej#;
h_buf# := gatei#;
define_pixels(w_buf,h_buf);

beginchar(17,w_buf#,h_buf#,0);  "Buffer, right";

x1 = x2 = 0;
x3 = gatej;

y1 = 0;
y2 = gatei;
y3 = gatek;

pickup pencircle scaled gatew;
draw z1--z2--z3--z1;

pic := currentpicture;

labels (range 1 thru 3);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Buffer, facing down
%

beginchar(18,h_buf#,w_buf#,0);  "Buffer, down";

currentpicture := pic rotated 270 shifted (0,w_buf);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Buffer, facing to the left
%

beginchar(19,w_buf#,h_buf#,0);  "Buffer, left";

currentpicture := pic rotated 180 shifted(w_buf,h_buf);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Buffer, facing up
%

beginchar(20,h_buf#,w_buf#,0);  "Buffer, up";

currentpicture := pic rotated 90 shifted(h_buf,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Inverter, facing to the right
%

w_inv# := gatej#+gatee#;
h_inv# := gatei#;
define_pixels(w_inv,h_inv);

beginchar(21,w_inv#,h_inv#,0);  "Inverter, right";

x1 = x2 = 0;
x3 = gatej;
x4 = x3 + gatee/2;

y1 = 0;
y2 = gatei;
y3 = y4 = gatek;


pickup pencircle scaled gatew;
draw z1--z2--z3--z1;
draw fullcircle scaled gatee shifted (z4);

pic := currentpicture;

labels (range 1 thru 4);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Inverter, facing down
%

beginchar(22,h_inv#,w_inv#,0);  "Inverter, down";

currentpicture := pic rotated 270 shifted (0,w_inv);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Inverter, facing to the left
%

beginchar(23,w_inv#,h_inv#,0);  "Inverter, left";

currentpicture := pic rotated 180 shifted(w_inv,h_inv);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       Inverter, facing up
%

beginchar(24,h_inv#,w_inv#,0);  "Inverter, up";

currentpicture := pic rotated 90 shifted(h_inv,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       XOR gate, facing to the right
%

w_xor# := gatef#+gateg#+gateh#;
h_xor# := gateb#;
define_pixels(w_xor,h_xor);

beginchar(25,w_xor#,h_xor#,0);  "XOR gate, right";

x1 = x2 = 0 + gatef;
x3 = x5 = gateg + gatef;
x4 = gateg + gateh + gatef;
x6 = gatef + gatef;
x7 = x8 = 0;
x9 = 0 + gatef;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = y6 = gatea;
y7 = 0;
y8 = gateb;
y9 = gatea;

pickup pencircle scaled gatew;
draw z1..z6..z2;
draw z2--z3;
draw z3{right}..{(1,-2)}z4;
draw z4{-1,-2}..z5{left};
draw z5--z1;
draw z8..z9..z7;

pic := currentpicture;

labels (range 1 thru 9);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       XOR gate, facing down
%

beginchar(26,h_xor#,w_xor#,0);  "XOR gate, down";

currentpicture := pic rotated 270 shifted (0,w_xor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       XOR gate, facing to the left
%

beginchar(27,w_xor#,h_xor#,0);  "XOR gate, left";

currentpicture := pic rotated 180 shifted(w_xor,h_xor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       XOR gate, facing up
%

beginchar(28,h_xor#,w_xor#,0);  "XOR gate, up";

currentpicture := pic rotated 90 shifted(h_xor,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NXOR gate (a.k.a. comparator), facing to the right
%

w_nxor# := gatef#+gateg#+gateh#+gatee#;
h_nxor# := gateb#;
define_pixels(w_nxor,h_nxor);

beginchar(29,w_nxor#,h_nxor#,0);  "NXOR gate, right";

x1 = x2 = 0 + gatef;
x3 = x5 = gateg + gatef;
x4 = gateg + gateh + gatef;
x6 = gatef + gatef;
x7 = x8 = 0;
x9 = 0 + gatef;
x10 = x4 + gatee/2;

y1 = y5 = 0;
y2 = y3 = gateb;
y4 = y6 = gatea;
y7 = 0;
y8 = gateb;
y9 = gatea;
y10 = y4;

pickup pencircle scaled gatew;
draw z1..z6..z2;
draw z2--z3;
draw z3{right}..{(1,-2)}z4;
draw z4{-1,-2}..z5{left};
draw z5--z1;
draw z8..z9..z7;
draw fullcircle scaled gatee shifted (z10);

pic := currentpicture;

labels (range 1 thru 10);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NXOR gate, facing down
%

beginchar(30,h_nxor#,w_nxor#,0);  "NXOR gate, down";

currentpicture := pic rotated 270 shifted (0,w_nxor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NXOR gate, facing to the left
%

beginchar(31,w_nxor#,h_nxor#,0);  "NXOR gate, left";

currentpicture := pic rotated 180 shifted(w_nxor,h_nxor);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%       NXOR gate, facing up
%

beginchar(32,h_nxor#,w_nxor#,0);  "NXOR gate, up";

currentpicture := pic rotated 90 shifted(h_nxor,0);

endchar;

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
%      lines to connect inputs of OR-like gates
%      N.B.: right/down facing inputs come before the gate,
%      left/up facing inputs after the gate!
%      The left/down lines have to be shifted by TeX, since 
%      this shift cannot be determined in advance for down-
%      facing lines.
%      Only the right-facing lines have a height, which should
%      be used to determine the exact place where connections
%      should enter the gate.
%

linea# := 0.2 * gateb#;
lineb# := 0.25 * (gateb# - (2 * linea#));
linec# := 0.3333 * (gateb# - (2 * linea#));

lineea# := 0.5 * gatef#;
lineeb# := 0.75 * gatef#;
lineec# := 0.87 * gatef#;
lineed# := 0.95 * gatef#;

define_pixels(linea,lineb,linec,lineea,lineeb,lineec,lineed);

beginchar(33,0,gateb#-linea#,0); "upper input facing right";
x1 = 0;
x2 = lineea;
y1 = y2 = gateb - linea;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(40,0,0,0); "upper input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(47,0,0,0); "upper input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(54,0,0,0); "upper input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(34,0,linea#,0); "lower input facing right";
x1 = 0;
x2 = lineea;
y1 = y2 = linea;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(41,0,0,0); "lower input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(48,0,0,0); "lower input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(55,0,0,0); "lower input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(35,0,linea#+(2*lineb#),0); "middle input facing right";
x1 = 0;
x2 = lineed;
y1 = y2 = linea + (2 * lineb);
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(42,0,0,0); "middle input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(49,0,0,0); "middle input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(56,0,0,0); "middle input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(36,0,gateb#-linea#-lineb#,0); "upper-middle input facing right";
x1 = 0;
x2 = lineeb;
y1 = y2 = gateb - linea - lineb;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(43,0,0,0); "upper-middle input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(50,0,0,0); "upper-middle input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(57,0,0,0); "upper-middle input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(37,0,linea#+lineb#,0); "lower-middle input facing right";
x1 = 0;
x2 = lineeb;
y1 = y2 = linea + lineb;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(44,0,0,0); "lower-middle input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(51,0,0,0); "lower-middle input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(58,0,0,0); "lower-middle input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(38,0,gateb#-linea#-linec#,0); "next-to-upper input facing right";
x1 = 0;
x2 = lineec;
y1 = y2 = gateb - linea - linec;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(45,0,0,0); "next-to-upper input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(52,0,0,0); "next-to-upper input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(59,0,0,0); "next-to-upper input facing up";
currentpicture := pic rotated 90;
endchar;

beginchar(39,0,linea#+linec#,0); "next-to-lower input facing right";
x1 = 0;
x2 = lineec;
y1 = y2 = linea + linec;
pickup pencircle scaled linew;
draw z1--z2;
pic := currentpicture;
labels (range 1 thru 2);
endchar;
beginchar(46,0,0,0); "next-to-lower input facing down";
currentpicture := pic rotated 270;
endchar;
beginchar(53,0,0,0); "next-to-lower input facing left";
currentpicture := pic rotated 180;
endchar;
beginchar(60,0,0,0); "next-to-lower input facing up";
currentpicture := pic rotated 90;
endchar;

end;