% Copyright (C) 1991 Silvio Levy % % This file 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 2 of the License, or % (at your option) any later version. % % This file 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, see . % % As a special exception, if you create a document which uses this font, % and embed this font or unaltered portions of this font into the % document, this font does not by itself cause the resulting document to % be covered by the GNU General Public License. This exception does not % however invalidate any other reasons why the document might be covered % by the GNU General Public License. If you modify this font, you may % extend this exception to your version of the font, but you are not % obligated to do so. If you do not wish to do so, delete this exception % statement from your version. if unknown gen_sigma: readfrom("gen_sigma") fi def dims = 8.5u#,asc_height#,0 enddef; def ital = 0 enddef; def fit_params = 0,0 enddef; def gen_letter = pickup fine.nib; top y1r=vround(if not monowidth:.95 fi x_height+oo); x1r=.5w; %top of loop x5r=.5w; bot y5r=-oo; %bottom of ditto lft x3r=w-rt x7r=hround(.75u); y3r=y7r=.5[y1r,y5r]; %left and right bulge filldraw stroke gr_arc.e(1,2,3)(vair,stem,.5otilt) %three quadrants of loop & gr_arc.e(3,4,5)(vair,stem,.5otilt) & gr_arc.e(5,6,7)(vair,stem,.5otilt); %we now draw the hook z8..z9..z10. It must satisfy the following constraints: %its outer contour is symmetric with respect to some axis containing z9l; %one end is known, the width there is thin_stem, and the width at z10 %is, ideally, stem. (But since we may have to change that we call it Stem.) z8l=z1l; numeric thin_stem, med_stem; thin_stem=.7[hair,Stem]; %the aperture, measured perpendicular to the axis, equals Stem numeric apert; apert=2Stem+thin_stem-currentbreadth; %apert=length(z10l-z8l); numeric left_goal; lft left_goal=vround(lft x3r+.5u); %leftmost tangent known numeric top_goal; top top_goal=h+oo; %highest tangent known %if by taking Stem=stem we got apert > top_goal-y1l, the problem might %not have a solution with a horizontal tangent; in that case the %constraint is on apert: if 2stem+.7[hair,stem]-currentbreadth>top_goal-y8l: apert=top_goal-y8l; else: Stem=stem; fi %we first estimate the slope of the axis by imagining that, in the vicinity %of z9l, the hook looks like a semicircle of diameter apert/2. %(this value is empiric, but reasonable because the tension is high) z0l=(left_goal+.25apert,top_goal-.25apert); %center of semicircle numeric axis; axis=angle(z0l-z8l)+angle(length(z0l-z8l)+-+.5apert,.5apert); z9l=z0l+(.25apert,0)rotated(axis); z10l=z8l+(0,-apert)rotated(axis); %we now iterate, correcting z9l until the tangencies are satisfied path hook; numeric left_real; numeric top_real; forever: hook:=z8l{dir(axis)}..tension 1.5..z9l..tension 1.5..{-dir(axis)}z10l; if directiontime up of hook=-1: left_error:=0; message "hook has no vertical tangent!"; else: left_error:=xpart directionpoint up of hook-left_goal; fi if directiontime right of hook=-1: top_error:=0; message "hook has no horizontal tangent!"; else: top_error:=ypart directionpoint right of hook-top_goal; fi %message "top_error:"; show top_error; message "left_error:"; show left_error; exitif (abs(left_error)<.05) and (abs(top_error)<.05); x9l:=x9l-left_error; y9l:=y9l-top_error; axis:=angle(z9l-z8l)+angle(length(z9l-z8l)+-+.5apert,.5apert); x10l:=x8l+apert*sind axis; y10l:=y8l-apert*cosd axis; endfor pos8(thin_stem,axis-90); pos10(Stem,axis+90); pos9(.3[hair,Stem],axis+180); filldraw stroke z7e{z7'e}..{dir axis}z8e..tension 1.5..z9e..tension 1.5..{-dir axis}z10e; enddef; cmchar "Lowercase delta"; beginchar("d",dims); this_letter; penlabels(1,2,3,4,5,6,7,8,9,10); endchar; if boolean barebones: picture savedpicture; endinput; fi cmchar "Lowercase sigma followed by delta"; begindoublechar(oct"004",dim_sigma); mid_sigma; middoublechar(dims); this_letter; endchar; picture savedpicture;