%======================================================================
% This is
%		pawn.mf
%
% Copyright (C) 1989-93  by Elmar Bartel.
%
% This program is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation; either version 1, or (at your option)
% any later version.
%
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

% This is the oldest part of all my the MF-sources.
% I started Metafonting with this figure.
%						ElB.
%======================================================================

%-----------------------------------------------------------
% This macro depends on some global sizes:
%	thin, BottomSpace, BottomWidth, sidewith 
% The values are defined as basic sizes of the Chess Characters

def PawnShape(expr wbf,hbf,wmf,hmf,wtf,htf,ibm,imt) =
	%begingroup
	%save wb,wm,wt,hb,hm,ht,interbm,intermt;
	numeric wb,wm,wt,hb,hm,ht,interbm,intermt;
	wb = BottomWidth*wbf;	    % width of bottom ellipse
	hb = hbf*wb;		    % hight of bottom ellipse
	wm = wmf*wb;  hm = hmf*wm;  % width and hight of middle ellipse
	wt = wtf*wb;  ht = htf*wt;  % width and hight of top ellipse
	interbm = ibm*thin;	    % amount of intersection of bottom
				    % and middle
	intermt = imt*thin;	    % amount of intersection of middle
				    %and top
	%save superb,superm,supert;
	numeric superb,superm,supert;
	superb=.73;
	superm=.75;
	supert=.73;

	%save topb,topm,topt;
	numeric topb,topm,topt;
	topb=BottomSpace+hb;
	topm=topb+hm-interbm;
	topt=topm+ht-intermt;

	%screenrule((0,BottomSpace),(qs,BottomSpace));
	%screenrule(((qs-wb)/2,0),((qs-wb)/2,qs));
	%screenrule(((qs+wb)/2,0),((qs+wb)/2,qs));

	%screenrule((0,topb),(qs,topb));
	%screenrule((0,topm),(qs,topm));
	%screenrule((0,topt),(qs,topt));

	%save bp,mp,tp;
	numeric bp,mp,tp;
	path bp,mp,tp,PawnPath;

	%save x,y,z;
	%pair z[]b,x[]b,y[]b;
	%pair z[]m,x[]m,y[]m;
	%pair z[]t,x[]t,y[]t;

	bot rt z1b = ((qs+wb)/2, BottomSpace);
	bot lft z3b = ((qs-wb)/2, BottomSpace);
	bot y4b + hb = top y2b - hb = BottomSpace;
	x2b = x4b = qs/2;
	bp=superellipse(z1b,z2b,z3b,z4b,superb);
	bp:= subpath(0,4) of bp;

	rt x1m - wm/2 = lft x3m + wm/2 = qs/2;
	top y2m = bot y4m + hm  = topm;
	y1m = y3m = (y2m+y4m)/2;
	x2m = x4m = qs/2;
	mp=superellipse(z1m,z2m,z3m,z4m,superm);

	rt x1t - wt/2 = lft x3t + wt/2 = qs/2;
	top y2t = bot y4t + ht = topt;
	y1t = y3t = (y2t+y4t)/2;
	x2t = x4t = qs/2;
	tp=superellipse(z1t,z2t,z3t,z4t,supert);

	% compute the intersectiontimes on the right side of the pawn
	% The pathtimes of superellipses range from 0 to 8

	%save scbr,scmbr,scmtr,sctr;
	numeric scbr,scmbr,scmtr,sctr;
	scbr = xpart (bp intersectiontimes (subpath(6,8)of mp));
	scmbr = xpart (mp intersectiontimes (subpath(0,2)of bp));
	scmtr = xpart (mp intersectiontimes (subpath(6,8)of tp));
	sctr = xpart (tp intersectiontimes (subpath(0,2)of mp));

	% here is a macro to mirror pathtimes of superellipses on y-axis
	def mr(expr v) = 
		if v > 4: 12-v;
		    else: 4-v;
		fi
	enddef;

	% Now the left intersectionpoints
	%save scbl,scmbl,scmtl,sctl;
	numeric scbl,scmbl,scmtl,sctl;
	scbl = mr(scbr);
	scmbl = mr(scmbr);
	scmtl = mr(scmtr);
	sctl = mr(sctr);

	PawnPath:=subpath(0,scbr)of bp ..
	  subpath(scmbr,(8+scmtr)) of mp ..
	  subpath(sctr,8+sctl) of tp ..
	  subpath(scmtl,scmbl) of mp ..
	  subpath(scbl,4) of bp;
	%endgroup

enddef;
%-----------------------------------------------------------
def MakePawnPath =
    pickup chess_pen;
    if unknown PawnPath:
	% wb = qs - 2*sidespace;	% width of bottom ellipse
	% hb = hbf*wb;			% hight of bottom ellipse
	% wm = wmf*wb;  hm = hmf*wm;	% width and hight of middle
					% ellipse
	% wt = wtf*wb;  ht = htf*wt;	% width and hight of top
					% ellipse
	%
	%               wbf, hbf, ,wmf, hmf, wtf, htf, ibm, imt
	%PawnShape(      .80, .50,  .55, .85,  .3, 1.0, 2.0, 1.2);
	%PawnShape(      .85, .55,  .60, .90,  .4, 1.0, 2.0, 1.2);
	PawnShape(      .77, .61,  .60, .84,  .35, 0.95, 1.8, 1.4);
    fi
enddef;
%------------------------------------------------------------
def CorrectPawnEdges =
	pickup sqr;
	drawdot(z1b);
	drawdot(z3b);
enddef;
%-----------------------------------------------------------

%we have to define six essential characters:
%         WoW   NoW   BoW   WoB   NoB   BoB
%Pawn       0     6    12    18    24    30
%Knight     1     7    13    19    25    31
%Bishop     2     8    14    20    26    32
%Rook       3     9    15    21    27    33
%Queen      4    10    16    22    28    34
%King       5    11    17    23    29    35

% All these cases are repeated three more times:
% Left turned, Right turned and upside down
%------------------------------------------


def MakeWhitePawn = 
	pickup chess_pen;
	clearit;
	MakePawnPath;
	draw PawnPath -- cycle;
	cullit;
	WhiteMan:= currentpicture;
enddef;

def MakeBlackPawn =
	pickup chess_pen;
	clearit;
	MakePawnPath;
	filldraw PawnPath -- cycle;
	cullit;
	BlackMan:= currentpicture;
enddef;

def MakeOuterShape =
	pickup frame_pen;
	clearit;
	filldraw PawnPath -- cycle;
	cullit;
	OuterShape:= currentpicture;
enddef;

MakeWhitePawn;
MakeBlackPawn;
MakeNeutral(WhiteMan, BlackMan);
MakeOuterShape;

%===========================================================
% this one for testing
%beginchar(Pawn+White+OnBlack, qs#, qs#, 0);
%	"White pawn on black field";
%	MakeBlackField;
%	currentpicture:= currentpicture - OuterShape;
%	cullit;
%	currentpicture:= currentpicture + WhiteMan;
%endchar;
%endinput
%===========================================================

beginchar(Pawn+White+OnWhite, qs#, qs#, 0);
	"White pawn on white field";
	currentpicture:= WhiteMan;
endchar;

beginchar(Pawn+White+OnWhite+LeftTurned, qs#, qs#, 0);
	"White pawn on white field rotated to the left";
	currentpicture:= TurnLeft(WhiteMan);
endchar;

beginchar(Pawn+White+OnWhite+RightTurned, qs#, qs#, 0);
	"White pawn on white field rotated to the right";
	currentpicture:= TurnRight(WhiteMan);
endchar;

beginchar(Pawn+White+OnWhite+UpSideDown, qs#, qs#, 0);
	"White pawn on white field upside down";
	currentpicture:= TurnUpSideDown(WhiteMan);
endchar;

beginchar(Pawn+Black+OnWhite, qs#, qs#, 0);
	"Black pawn on white field";
	currentpicture:= BlackMan;
endchar;

beginchar(Pawn+Black+OnWhite+LeftTurned, qs#, qs#, 0);
	"Black pawn on white field rotated to the left";
	currentpicture:= TurnLeft(BlackMan);
endchar;

beginchar(Pawn+Black+OnWhite+RightTurned, qs#, qs#, 0);
	"Black pawn on white field rotated to the right";
	currentpicture:= TurnRight(BlackMan);
endchar;

beginchar(Pawn+Black+OnWhite+UpSideDown, qs#, qs#, 0);
	"Black pawn on white field upside down";
	currentpicture:= TurnUpSideDown(BlackMan);
endchar;

beginchar(Pawn+Neutral+OnWhite, qs#, qs#, 0);
	"Neutral pawn on white field";
	currentpicture:= NeutralMan;
endchar;

beginchar(Pawn+Neutral+OnWhite+LeftTurned, qs#, qs#, 0);
	"Neutral pawn on white field rotated to the left";
	currentpicture:= TurnLeft(NeutralMan);
endchar;

beginchar(Pawn+Neutral+OnWhite+RightTurned, qs#, qs#, 0);
	"Neutral pawn on white field rotated to the right";
	currentpicture:= TurnRight(NeutralMan);
endchar;

beginchar(Pawn+Neutral+OnWhite+UpSideDown, qs#, qs#, 0);
	"Neutral pawn on white field upside down";
	currentpicture:= TurnUpSideDown(NeutralMan);
endchar;

beginchar(Pawn+White+OnBlack, qs#, qs#, 0);
	"White pawn on black field";
	MakeBlackField;
	currentpicture:= currentpicture - OuterShape;
	cullit;
	currentpicture:= currentpicture + WhiteMan;
endchar;

beginchar(Pawn+White+OnBlack+LeftTurned, qs#, qs#, 0);
	"White pawn on black field turned to the left";
	MakeBlackField;
	currentpicture:= currentpicture - TurnLeft(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnLeft(WhiteMan);
endchar;

beginchar(Pawn+White+OnBlack+RightTurned, qs#, qs#, 0);
	"White pawn on black field turned to the right";
	MakeBlackField;
	currentpicture:= currentpicture - TurnRight(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnRight(WhiteMan);
endchar;

beginchar(Pawn+White+OnBlack+UpSideDown, qs#, qs#, 0);
	"White pawn on black field upsidedown";
	MakeBlackField;
	currentpicture:= currentpicture - TurnUpSideDown(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnUpSideDown(WhiteMan);
endchar;

beginchar(Pawn+Neutral+OnBlack, qs#, qs#, 0);
	"Neutral pawn on black field";
	MakeBlackField;
	currentpicture:= currentpicture - OuterShape;
	cullit;
	currentpicture:= currentpicture + NeutralMan;
endchar;

beginchar(Pawn+Neutral+OnBlack+LeftTurned, qs#, qs#, 0);
	"Neutral pawn on black field turned to the left";
	MakeBlackField;
	currentpicture:= currentpicture - TurnLeft(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnLeft(NeutralMan);
endchar;

beginchar(Pawn+Neutral+OnBlack+RightTurned, qs#, qs#, 0);
	"Neutral pawn on black field turned to the right";
	MakeBlackField;
	currentpicture:= currentpicture - TurnRight(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnRight(NeutralMan);
endchar;

beginchar(Pawn+Neutral+OnBlack+UpSideDown, qs#, qs#, 0);
	"Neutral pawn on black field upsidedown";
	MakeBlackField;
	currentpicture:= currentpicture - TurnUpSideDown(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnUpSideDown(NeutralMan);
endchar;

beginchar(Pawn+Black+OnBlack, qs#, qs#, 0);
	"Black pawn on black field";
	MakeBlackField;
	currentpicture:= currentpicture - OuterShape;
	cullit;
	currentpicture:= currentpicture + BlackMan;
endchar;

beginchar(Pawn+Black+OnBlack+LeftTurned, qs#, qs#, 0);
	"Black pawn on black field turned to the left";
	MakeBlackField;
	currentpicture:= currentpicture - TurnLeft(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnLeft(BlackMan);
endchar;

beginchar(Pawn+Black+OnBlack+RightTurned, qs#, qs#, 0);
	"Black pawn on black field turned to the right";
	MakeBlackField;
	currentpicture:= currentpicture - TurnRight(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnRight(BlackMan);
endchar;

beginchar(Pawn+Black+OnBlack+UpSideDown, qs#, qs#, 0);
	"Black pawn on black field upsidedown";
	MakeBlackField;
	currentpicture:= currentpicture - TurnUpSideDown(OuterShape);
	cullit;
	currentpicture:= currentpicture + TurnUpSideDown(BlackMan);
endchar;