1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
|
%% sgbx0023.mp
%% Copyright 2006 Tommy Ekola <tek@kth.se>
%
% This work may be distributed and/or modified under the conditions of
% the LaTeX Project Public License, either version 1.3 of this license
% or (at your option) any later version. The latest version of this
% license is in http://www.latex-project.org/lppl.txt
%
% This work has the LPPL maintenance status `maintained'. The Current
% Maintainer of this work is Tommy Ekola. The Base Interpreter is
% MetaPost.
vardef setup_tailarrow (expr source_file, cmdname) =
scantokens ("input tgbx0000");
scantokens ("input " & source_file);
expandafter def scantokens cmdname expr p =
scantokens (cmdname & "__sgbxww")(p)
enddef;
expandafter vardef scantokens (cmdname & "__sgbxww " & "(expr apth) " &
"text text_ = " &
"save math_spread, x_height, u, rule_thickness, bar, math_axis," &
" asc_height, eps, monospace, fudge, crisp, hair;" &
"boolean monospace;" &
"math_spread :=" & decimal math_spread & ";" &
"x_height# :=" & decimal x_height# & ";" &
"u# :=" & decimal u# & ";" &
"rule_thickness# :=" & decimal rule_thickness# & ";" &
"bar# :=" & decimal bar# & ";" &
"math_axis# :=" & decimal math_axis# & ";" &
"asc_height# :=" & decimal asc_height# & ";" &
"eps :=" & decimal eps & ";" &
"monospace :=" & if monospace: "true" else: "false" fi & ";" &
"fudge :=" & decimal fudge & ";" &
"crisp# :=" & decimal crisp# & ";" &
"hair# :=" & decimal hair# & ";")
save prevpen;
prevpen:=savepen;
save x,y;
numeric x[], x[]', x[]l, x[]'l, x[]r, x[]'r,
y[], y[]', y[]l, y[]'l, y[]r, y[]'r;
save spread, w;
numeric spread, w;
if crisp#>fudge*hair#:
crisp#:=fudge*hair#;
fi
pickup if crisp#=0: nullpen else: pencircle scaled crisp# fi;
spread = math_spread[.45x_height#, .55x_height#];
w = 18u#;
penpos1(rule_thickness#, 90); penpos2(rule_thickness#, 90);
penpos3(bar#, 0); penpos4(bar#, 0);
y0=y1=y2=math_axis#; x1-.5rule_thickness#=u#; rt x0=w-u#;
y3-y0=y0-y4=.24asc_height#+eps;
x3=x4=x0-3u#-eps;
penpos5(bar#, angle(z4-z0)); z5l=z0;
penpos6(bar#, angle(z3-z0)); z6l=z0;
z9=.381966[.5[z3,z4],z0];
save pp; path pp; pp = z4l{z9-z4}..z6r;
save t; numeric t; t = xpart(pp intersectiontimes ((0,y2l)--(w,y2l)));
x2=xpart point t of pp;
save mapto, n;
vardef mapto(text t) =
hide(numeric n; n:=0;
numeric x,x_[],y,y_[];
for z=t: z_[incr n]:=z; endfor;
transform T;
z_2 = z_1 transformed T;
z_4 = z_3 transformed T;
z_6 = z_5 transformed T;)
T
enddef;
save T; transform T;
save tt; numeric tt; tt = arctime(arclength apth - (x0-x9)) of apth;
save ttt; numeric ttt; ttt = arctime(arclength apth - (x0-x2)) of apth;
save ssss; numeric ssss; ssss = arctime(x0-x3l) of apth;
% Draw the right half of the arrowhead
save right_texarrowhead, pa;
vardef right_texarrowhead(expr T,s) =
(subpath(0, xpart ((z0..{z4-z9}z4r) intersectiontimes
(point s of pp -- point s of pp + (2rule_thickness#,0))))
of (z0..{z4-z9}z4r)--subpath(s,t) of pp--z2l) transformed T
enddef;
if arclength apth = 0:
T:=identity shifted (point (length apth) of apth - z0);
elseif arclength apth < x0-x3l:
T:=identity rotatedaround(z0,angle (direction (length apth) of apth))
shifted (point (length apth) of apth -z0);
else:
T:=mapto(z0,
point (length apth) of apth,
z2,
point ttt of apth,
z9+(0,3rule_thickness#),
point tt of apth +
3rule_thickness#*(unitvector (direction tt of apth)
rotated 90));
fi
save f,s;
vardef f(expr s) =
length(point s of (pp transformed T) - point tt of apth)
< length(point 0 of pp - z9)
enddef;
if f(0) or (arclength apth < x0-x3l): s := 0;
else: s := solve f(length pp, 0);
fi
path pa;
pa := right_texarrowhead(T,s);
% Draw the left half of the arrow head
pp := (z3l{z9-z3}..z5r);
save pq; path pq; pq := (z3r{z9-z3}..z0);
save left_texarrowhead, pb;
vardef left_texarrowhead(expr T, s) =
(z2r--subpath(t,s) of pp
--subpath(xpart ( pq intersectiontimes
(point s of pp -- point s of pp + (2rule_thickness#,0)))
,length pq) of pq) transformed T
enddef;
if arclength apth = 0:
T:=identity shifted (point (length apth) of apth - z0);
elseif arclength apth < x0-x3l:
T:=identity rotatedaround(z0,angle (direction (length apth) of apth))
shifted (point (length apth) of apth - z0);
else:
T:=mapto(z0,
point (length apth) of apth,
z2,
point ttt of apth,
z9+(0,3rule_thickness#),
point tt of apth + 3rule_thickness#
*(unitvector (direction tt of apth)
rotated 90));
fi
vardef f(expr s) =
length(point s of (pp transformed T) - point tt of apth)
< length(point 0 of pp - z9)
enddef;
if f(0) or (arclength apth < x0-x3l): s := 0;
else: s := solve f(length pp, 0);
fi
path pb;
pb := left_texarrowhead(T,s);
filldraw pa--pb--cycle text_;
% Draw the right half of the tail
save ss; ss := arctime(x9-x3l) of apth;
save sss; sss := arctime(x2-x3l) of apth;
if arclength apth = 0:
T:=identity shifted (point 0 of apth - z0);
elseif arclength apth < x0-x3l:
T:=identity rotatedaround(z0,angle (direction 0 of apth))
shifted (point 0 of apth - z0);
else:
T:=mapto(z0,
point ssss of apth,
z2,
point sss of apth,
z9+(0,3rule_thickness#),
point ss of apth +
3rule_thickness#*(unitvector (direction ss of apth)
rotated 90));
fi
pp := z4l{z9-z4}..z6r;
vardef f(expr s) =
length(point s of (pp transformed T) - point ss of apth)
< length(point 0 of pp - z9)
enddef;
if f(0) or (arclength apth < x0-x3l): s := 0;
else: s := solve f(length pp, 0);
fi
pa := right_texarrowhead(T,s);
% Draw the left half of the tail
if arclength apth = 0:
T:=identity shifted (point 0 of apth - z0);
elseif arclength apth < x0-x3l:
T:=identity rotatedaround(z0,angle (direction 0 of apth))
shifted (point 0 of apth - z0);
else:
T:=mapto(z0,
point ssss of apth,
z2,
point sss of apth,
z9-(0,3rule_thickness#),
point ss of apth -
3rule_thickness#*(unitvector (direction ss of apth)
rotated 90));
fi
pp := (z3l{z9-z3}..z5r);
pq := (z3r{z9-z3}..z0);
vardef f(expr s) =
length(point s of (pp transformed T) - point ss of apth)
< length(point 0 of pp - z9)
enddef;
if f(0) or (arclength apth < x0-x3l): s := 0;
else: s := solve f(length pp, 0);
fi
pb := left_texarrowhead(T,s);
filldraw pa--pb--cycle text_;
% Draw the path
if arclength apth > 2(x0-x2):
save stt; stt := arctime(.5(x0+x2)-x3l) of apth;
draw subpath(stt,ttt) of apth withpen pencircle scaled rule_thickness#
text_;
fi
pickup prevpen;
enddef;
enddef;
|
