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
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
|
% vim: tw=80
\_def\_pdfextra_version{0.1}
\_codedecl \RM {Extra PDF features (v\_pdfextra_version)}
\_doc
\sec Package initialization
We are in the \OpTeX/ package namespace. A couple of shortcuts are defined
here: \`\.isdefined`, \`\.trycs`, \`\.cs` \`\.slet`, \`\.slet`, \`\.sdef` and
\`\.xdef`. They all hard code the package name, because we already have too
many levels of indirection.
\_cod
\_namespace{pdfextra}
\_def\.isdefined#1{\_isdefined{_pdfextra_#1}}
\_def\.trycs#1{\_trycs{_pdfextra_#1}}
\_def\.cs#1{\_cs{_pdfextra_#1}}
\_def\.slet#1#2{\_slet{_pdfextra_#1}{_pdfextra_#2}}
\_def\.sdef#1{\_sdef{_pdfextra_#1}}
\_def\.sxdef#1{\_sxdef{_pdfextra_#1}}
\_doc
\sec Helper macros
The macros here are just helpers for the macros to follow. They are not
useful generally, but proved useful in the expandable context of writing to
PDF files.
Already the first one limits the use to \LuaTeX/ (but who needs other engines
anyways :). \`\.emptyor`<possibly empty text><text to use when first argument is
nonempty> checks whether the first argument is empty, if not it expands the
second argument which can use the text from the first argument with
\`\.nonempty`. \`\.attrorempty`<attribute name><value> builds upon the first
one and is really useful for PDF dictionaries, when we don't want to write an
attribute without a value (a default specified by standard will be used instead).
\_cod
\_def\.emptyor#1#2{%
\_immediateassignment\_edef\.nonempty{#1}%
\_ifx\.nonempty\_empty\_else #2\_fi
}
\_def\.attrorempty#1#2{\.emptyor{#2}{/#1 \.nonempty}}
\_doc
There is a dillema for handling colors. While typesetting it is possible to
use greyscale, CMYK or RGB colors. But there are contexts where it is
possible to only use RGB colors. We want to provide the user with two
possibilities of specifying colors:
\begitems
* RGB color using PDF triplet (e.g. `1 0 0`),
* \OpTeX/ color using control sequence (e.g. `\Blue`)
\enditems
Both are handled by \`\.colortorgbdef`<cs><color specification>, which
defines <cs> to the corresponding PDF RGB triplet. The indirection with
defining a macro is because we want to use the processed color within
expansion only contexts where grouping is not possible.
\_cod
\_def\.colortorgbdef#1#2{\_bgroup
\_def\_setrgbcolor##1{##1}%
\_def\_setcmykcolor##1{\_cmyktorgb ##1 ;}%
\_def\_setgreycolor##1{##1 ##1 ##1}%
\_xdef#1{#2}%
\_egroup
}
\_doc
\`\.xaddto``\macro`{<text>} is a natural extension of \OpTeX's `\addto` that
expands <text> and is global.
\_cod
\_def\.xaddto#1#2{\_edef\.tmp{#2}%
\_global\_ea\_addto\_ea#1\_ea{\.tmp}%
}
\_doc
This package defines a few commands in the form
`\macro[<name>][<optional arguments>]{<text>}`. To make it possible to omit
the `[<optional arguments>]` \`\.secondoptdef` is defined.
`\.secondoptdef\<macro><parameters>{<body>}`
defines `\macro` with first mandatory argument in brackets (saved to
\`\.name`). Second optional argument in brackets is scanned using helper
macro defined with `\optdef` and is saved to `\_opt` token list). Additional
<parameters> can be specified as with `\optdef` (numbered from `#1`).
\_cod
\_def\.secondoptdef#1{%
\_def#1[##1]{\_def\.name{##1}\.cs{sopt:\_string#1}}%
\_ea\_optdef\_csname _pdfextra_sopt:\_string#1\_endcsname[]%
}
\_doc
When processing comma separated lists sometimes it is needed to ignore the
remaining text. For this we use \`\.untilend` macro which ignores everything
up to dummy \`\.end`. This is analogous to \OpTeX/'s `\_finbody` used for the
same purpose. Sometimes `\.end` is used as sentinel and compared in `\ifx`
tests, hence we define it to a unique value.
\_cod
\_def\.untilend#1\.end{}
\_def\.end{_pdfextra_end}
\_doc
For various uses it is necessary to know the number of page where something
happens. This has to be handled asynchronously with `\write`. Here we use
\OpTeX/ specific `.ref` file and associated macros, but this could be
replaced as long as the same interface is exposed.
\`\.setpageof`<name> writes \`\.Xpageof`<name> to the `.ref` file. In the next
\TeX/ run `\.Xpageof` finds out the page number (`\gpageno`) from \OpTeX/'s
`\_currpage` and saves it so that \`\.pageof`<name> can retrieve it. In the
first run we can't be sure of the page where the content will end up. As a
rough estimate we take the current page~-- this actually works well for
slides where page breaks are manual.
`\.pageof` is expandable, but we want to let the user know, that the document
needs to be processed twice. Therefore we use \LuaTeX's
`\immediateassignment` to increment the counter of unresolved references.
When `.ref` file is read along with the defintion of `\.Xpageof` this package
has not been loaded yet. Hence we can't use namespaced variants of
`\.isdefined`, etc.
\_cod
\_refdecl{%
\_def\.Xpageof#1{\_isdefined{_pdfextra_pageof:#1}\_iffalse
\_sxdef{_pdfextra_pageof:#1}{\_ea\_ignoresecond\_currpage}\_fi
}%
}
\_def\.setpageof#1{\_openref \_ewref\.Xpageof{{#1}}}
\_def\.pageof#1{%
\.trycs{pageof:#1}{%
\_immediateassignment\_incr\_unresolvedrefs
\_the\_numexpr\_gpageno+1\_relax % best effort = current page num
}%
}
\_doc
\label[files]
\sec Handling of files
Handling of files is a big topic of this package. Files are everywhere~--
files containing multimedia, JavaScript script files, attachments, externally
referred files\dots Therefore a more sophisticated mechanism for handling
files is needed. The mechanism introduced in this section handles all three
cases of a {\em file specification}:
\begitems
* files embedded in the PDF (\"e", embedded file),
* files determined by path (\"x", external file),
* files determined by URL (\"u", url file).
\enditems
Although ideally all three would be interchangible this is not always the
case, because e.g. some media files must be embedded and linking to external
resources does not work with embedded files.
In most cases there are two many names and other associated values involved:
\begitems
* Some kind of a \"friendly" name. This one is sometimes shown by PDF viewers.
* The real name of the file. Also shown but in different contexts.
* The path or URL used to determine the file.
* MIME type of the file.
\enditems
For example when talking about \OpTeX/'s documentation we might have a
friendly name of \"opdoc", file name of \"`optex-doc.pdf`", URL of
\"\url{http://petr.olsak.net/ftp/olsak/optex/optex-doc.pdf}" and MIME type of
\"application/pdf". Different subset of them is required in different
contexts, but the user should only have to specify the friendly name (by
which they will refer to the file) and the path/URL of the file. The rest
will be deduced. The friendly name is used as a handle and {\em is usable}
in all places where file specification is required (although it may not
produce conforming output, see above).
In this two step process~-- definition and (re)use~-- we introduce a command
for defining files: \`\filedef``/<type> [<friendly name>]{<path or URL>}`. The
macro itself does general definitions and dispatches the type dependant work
to other macros in the form `_filedef:<type>`.
\_cod
\_def\.filedef/#1#2[#3]#4{%
\.sxdef{filename:#3}{(\.filename{#4})}%
\_edef\.tmp{\.exttomime{\.fileext{#4}}}%
\_ifx\.tmp\_empty
\_opwarning{MIME type of '#4' unknown, using '\.defaultmimetype'}%
\_edef\.tmp{\.defaultmimetype}%
\_fi
\.sxdef{filemime:#3}{\.tmp}%
\.cs{filedef:#1}{#3}{#4}%
}
\_nspublic \filedef ;
\_doc
Types \"e", \"x", \"u" are predefined, anything else would essentialy be a
variant of these.
External file (\"x") is determined only by path.
\_cod
\.sdef{filedef:x}#1#2{%
\.slet{filespec:#1}{filename:#1}%
}
\_doc
URL file (\"u") is determined by URL. Using all sorts of characters is
allowed by using `\_detokenize`. This time it is necessary to create full
{\em file specification}~-- a dictionary, where the \"file system" is URL.
\_cod
\.sdef{filedef:u}#1#2{%
\.sdef{filespec:#1}{<</FS /URL /F (\_detokenize{#2})>>}%
}
\_doc
Embedded files (\"e") are the most interesting ones. For further use (e.g.
for displaying the embedded files as attachments) MIME type is required. It
is saved in the stream as a `\Subtype`, encoded as a PDF name (e.g.
`/video#2Fmp4`). The embedded file stream must be wrapped in a full {\em file
specification}, which has the `/EF` (\"embedded file") entry. Also the
friendly name is used for some purpose by PDF viewers, so it set in `/Desc`
(description).
\_cod
\.sdef{filedef:e}#1#2{%
\_edef\.tmp{\.cs{filemime:#1}}%
\_isfile{#2}\_iffalse
\_opwarning{file '#2' not found}%
\_fi
\_pdfobj stream
attr{/Type /EmbeddedFile /Subtype \_ea\.mimetoname\_ea[\.tmp]}
file {#2}%
\_pdfrefobj\_pdflastobj
\.sxdef{filestream:#1}{\_the\_pdflastobj\_space 0 R}%
\_pdfobj {<</Type /Filespec
/F \.cs{filename:#1}
/Desc (#1)
/EF << /F \_the\_pdflastobj \_space 0 R >>%
>>}%
\_pdfrefobj\_pdflastobj
\.sxdef{filespec:#1}{\_the\_pdflastobj\_space 0 R}%
}
\_doc
Now the less interesting part~-- determining the file names from paths and
determining MIME types. The file name is the part after the last \"`/`" (if
any). The file extension is the part after last \"`.`" (if any).
\_cod
\_def\.filename#1{\_ea\.filenameA#1/\.end}
\_def\.filenameA#1/#2{\_ifx\.end#2#1\_else\_afterfi{\.filenameA#2}\_fi}
\_def\.fileext#1{\_ea\.fileextA#1.\.end}
\_def\.fileextA#1.#2{\_ifx\.end#2#1\_else\_afterfi{\.fileextA#2}\_fi}
\_doc
MIME type is determined from file extension (e.g. `mp4` is \"video/mp4"). For
mapping of file extensions to MIME types we abuse \TeX/'s hash table which
gets populated with \"known MIME types". This necessarily means that the
database is incomplete. Users can define their own additional mappings, or
they can contribute generally useful ones to this package.
The default MIME type (used for unknown file extensions) is
\"application/octet-stream"~-- binary data.
The uninteresting MIME type database itself is at the very end (\ref[mime]).
\_cod
\_def\.mimetoname[#1/#2]{/#1\_csstring\#2F#2}
\_def\.defaultmimetype{application/octet-stream}
\_def\.exttomime#1{\.trycs{mimetype:#1}{}}
\_doc
Here we define an \OpTeX/ style \"is-macro" that checks whether the file has
already been defined~-- \`\.isfiledefined``{<name>}\iftrue` (or `\iffalse`).
The case where the file has not
been defined using `\filedef` can be handled in a lot of ways. As a default
we interpret <name> as path and try to embed it. Because the path from <name>
is used as the \"friendly name" the file will be embedded only once even when
requested more times.
\_cod
\_def\.isfiledefined#1#2{\.isdefined{filespec:#1}\_iftrue\_else
\_afterfi{\.fileundefined{#1}}\_fi#2%
}
\_def\.fileundefined#1{\_isfile{#1}\_iftrue\.filedef/e[#1]{#1}\_else
\_opwarning{file '#1' not found, ignored}\_ea\_unless\_fi
}
% strict requirement of preceeding `\filedef` can be set like this:
%\_def\.fileundefined#1{\_opwarning{file '#1' is not defined, ignored}\_unless}
\_doc
\label[actions]
\sec PDF actions
The core of interactivity in PDF are actions. They are all initialy handled
by \`\pdfaction``[<action spec>]`. <action spec> is a comma separated list of
`<type>:<arguments>`. Leading spaces in the elements of the list are ignored
using undelimited-delimited argument pair trick.
An invocation could look like this:
\begtt
\pdfaction[
js:{app.alert("Yay JavaScript, going to page 5");},
ilink:pg:5,
transition:Wipe,
]
\endtt
This is why we have to be very careful when loading the contents between `[]`
to arguments. In particular, we can't split immediatly using `[#1:#2]`,
because this would discard the braces guarding the comma in the JavaScript
code. However we also need to find out the {\em type} of action which is
taken as a type of the first action (`js` in this case).
\`\.pdfactiontype``[<action spec>]` does this~-- we don't mind that there the
braces are lost.
`\pdfaction` processes the list, to create a chain of actions using `/Next`
field. The handling of each action type is up to macro
`\_pdfextra_<type>action`, which receives `[<type>:<arguments>]`. Because of
this a single type handler can handle multiple different actions, as is the
case with `\.ilinkaction` which is the fallback for unknown action types.
\_cod
\_def\.pdfaction[#1#2]{\.pdfactionA#1#2,\.stop\.end}
\_def\.pdfactionA#1,#2#3\.end{%
<<%
\.pdfactionB[#1]%
% next action
\_ifx\.stop#3\_else\_space
/Next \_afterfi{\.pdfactionA#2#3\.end} % intentional space
\_fi
>>
}
\_def\.pdfactionB[#1:#2]{\.trycs{#1action}{\_ea\.ilinkaction}[#1:#2]}
\_nspublic \pdfaction ;
\_def\.pdfactiontype[#1:#2]{#1}
\_doc
\label[actions-additional]
\secc Additional actions
Some PDF objects, like pages and some annotations, can also have \"additional
actions". These are actions which will be executed when an event happens~--
like page getting opened for `/O` action in page's additonal actions or `/PO`
in annotation's additional actions. For constructing these additional actions
we define a helper macro \`\.pdfaactions`. The use is as something follows:
\begtt \catcode`<=13 \adef|{\csstring<}
/AA || \.pdfaactions{ {O} {<action spec 1>} {C} {<action spec 2>} } >>
\endtt
To produce something this:
\begtt \catcode`<=13 \adef|{\csstring<}
/AA || /O ||<action 1>>> /C ||<action 2>>> >>
\endtt
\_cod
\_def\.pdfaactions#1{<<\.pdfaactionsA #1\.end\.end>>}
\_def\.pdfaactionsA#1#2{\_ifx\.end#1\_else /#1 \_ea\.pdfaction\_ea[#2]\_ea\.pdfaactionsA\_fi}
\_doc
\label[actions-link]
\secc Link annotations
The main use of actions~-- annotations of `/Subtype /Link`.
Annotation of this type creates an active rectangular area on the page that
executes a PDF action (or chain of them in the general case).
\`\hlinkactive``[<action spec>]<text>` is a natural extension of \OpTeX/'s
`\linkactive`, that supports the classic \"jump" actions of types `ref`,
`bib`, etc. But also other types of actions. No distinction between
\"internal" (`\ilink`) and external (`\ulink`) links is made. The mechanism is
completely generic.
The `\pdfstartlink`/`\pdfendlink` primitives are used to denote the part of
the page where <text> appears as active. \LuaTeX/ will then handle even the
situations where <text> gets broken across multiple lines (by creating
multiple rectangular annotations to cover all `\hbox`es).
\_cod
\_def\.hlinkactive[#1]#2{\_bgroup\_def\#{\_csstring\#}%
\_edef\.type{\.pdfactiontype[#1]}%
\_quitvmode\_pdfstartlink \.linkdimens
attr{\_pdfborder{\.type}}%
user{/Subtype /Link /A \.pdfaction[#1]}\_relax
\_localcolor\.linkcolor{\.type}#2\_pdfendlink\_egroup
}
\_doc
`\hlinkactive` itself is dormant before `\hyperlinks` occurs. Until then, a
dummy \`\hlink` is used. \OpTeX/'s `\hyperlinks` is extended to hook `\hlink`
activation. The colors of internal/external links are remembered for
compatibility with \OpTeX/.
\_cod
\_def\.hlink[#1]#2{\_quitvmode{#2}}
\_nspublic \hlink ;
\_let\.oldhyperlinks\_hyperlinks
\_def\_hyperlinks#1#2{%
\.oldhyperlinks#1#2
\_let\.ilinkcolor=#1%
\_let\.elinkcolor=#2%
\_let\.hlink=\.hlinkactive
\_let\hlink=\.hlink
}
\_public \hyperlinks ;
\_doc
Two customizations of `\hlinks` are possible:
\begitems
* Dimensions of rectangular areas created by
`\pdfstartlink`/`\pdfendlink`. This is done using \`\.linkdimens`
(analogous to \OpTeX's `\linkdimens`). Dimensions that are unset are taken
from the respective `\hbox`es. \`\lininglinks` sets the dimensions for
running text~-- it covers all space of a line using `\baselineskip`.
\`\nolininglinks` sets no dimensions, this is useful for buttons, that may
have larger height/depth than a line.
* The color is determined from the type of link (that is the first action in
<action spec>) by checking `\_<type>linkcolor` (compatible with \OpTeX/) or
`\_pdfextra_<type>linkcolor`.
As a fallback \`\.ilinkcolor` is used (set by `\hyperlinks`).
\enditems
\_cod
\_def\.lininglinks{%
\_def\.linkdimens{height.75\_baselineskip depth.25\_baselineskip}%
}
\_def\.nolininglinks{\_def\.linkdimens{}}
\.lininglinks
\_nspublic \lininglinks \nolininglinks ;
\_def\.linkcolor#1{\_trycs{_#1linkcolor}{\.trycs{#1linkcolor}{\.ilinkcolor}}}
\_def\.ilinkcolor{}
\_doc
\secc Open action
The document itself has one action defined in the document catalog. It is
called `/OpenAction`. We allow the user to set it using the familiar
<action spec> syntax with the command \`\openaction``[<action spec>]`.
Internally we could directly set it by appending to the catalog
using the primitive `\pdfcatalog`, but \LuaTeX/ (pdf\TeX/ really) allows
setting the action with special syntax. This has the benefit that it is not
allowed to set the action more than once.
\_cod
\_def\.openaction[#1]{\_pdfcatalog{} openaction user{\.pdfaction[#1]}\_relax}
\_nspublic \openaction ;
\_doc
\label[actions-jump]
\secc Jump actions
These are the most typical actions. Even \LuaTeX/ itself handles them,
although we don't use the possibility for maintaining generality. There are a
few types of jump actions:
\begitems
* `/GoTo` actions are the classic internal links to named destinations in the
PDF file (created by `\pdfdest` primitive or \OpTeX/'s `\dest`). The
destination names include also the type of internal link (e.g.
`ref:section1`). They are handled by \`\.ilinkaction``[<type>:<name>]`.
* `/URI` actions which are in most cases used as \"goto URL" actions. These
are not that useful directly, because special characters should be handled
before this actions is used (like with `\url`). The low level use is
\`\.urlaction``[url:<url>]`.
* \"Goto remote" actions, which can jump to a destination in another PDF file~--
either determined by name, or by page number. The external files are
expected to be defined by `\filedef` (but not the embedded variant). The
use is either \`\.extrefaction``[extref:<name>:<named destination>]` for
links to named destination or \`\.extpgrefaction``[extpgref:<name>:<page number>]`
for page destinations. Customization is possible with \`\.extrefextra`, by
default opening in a new windows is requested.
\enditems
\_cod
\_def\.ilinkaction[#1:#2]{/S /GoTo /D (#1:#2)}
\_def\.urlaction[#1:#2]{/S /URI /URI (#2)}
\_def\.extrefaction[#1:#2:#3]{/S /GoToR
/F \.cs{filespec:#2}
/D (#3)
\.extrefextra
}
\_def\.extpgrefaction[#1:#2:#3]{/S /GoToR
/F \.cs{filespec:#2}
/D [\_the\_numexpr#3-1\_relax\_space /Fit]
\.extrefextra
}
\_def\.extrefextra{/NewWindow true}
\_doc
Transition action is not really a jump action in of itself, but is only
useful when chained after jump actions, so we define it here. Transitions
(as page attributes) are handled more thoroughly in section~\ref[transitions].
The use would look something like:\nl
\`\.transitionaction`%
`[transition:<animation type>:<duration>:<raw PDF attributes>]`, where all fields
omitted from right take the default values.
\_cod
\_def\.transitionaction[#1:#2]{/S /Trans \.attrorempty{Trans}{\.maketrans[#2]}}
\_doc
\secc Named actions
User can request arbitrary \"named" action with
\`\.namedaction``[named:<name>]`. See user documentation for details.
\_cod
\_def\.namedaction[#1:#2]{/S /Named /N /#2}
\_doc
\secc JavaScript actions
JavaScript actions have two forms, either \`\.jsaction``[js:<name>]` or
`\.jsaction``[js:<script>]`. The first variant uses contents of `\filedef`'d
<name>, the second one uses <script> directly. There is no special catcode
handling.
\_cod
\_def\.jsaction[#1:#2]{/S /JavaScript
/JS \_ifcsname _pdfextra_filestream:#2\_endcsname \_lastnamedcs \_else
(#2)
\_fi
}
\_doc
\sec Page attributes
PDF represents pages as dictionaries. The dictionaries get generated by \LuaTeX/,
which fills in some attributes {\em attributes} (like `/Content` with
contents of the page and `/Annots` with array of annotations). We can add
more using `\pdfpageattr` primitive token list register. While not that many
are generally useful, there are a few interesting ones. For example
transitions can be set using page attributes, or we might want to set
additional actions (`/AA`) to listen for page events.
While the so called \"page objects" are in a tree structure (for fast lookup),
only the leaves are real \"pages". PDF allows some attributes to be inherited
from parent page objects, but not all of them and certainly not those we are
interested in.
The mechanism introduced in this section is optional, because it takes
complete control over `\pdfpageattr`. It gets activated when
\`\initpageattributes` is first used (which happens automatically for some
functionality exposed by this package), but may be activated by the user for
any other purpose. Only attributes listed in \`\pageattributes` are
processed.
We set the attributes anew for each page, by hooking into \OpTeX/'s
`\_begoutput`. Because `\pdfpageattr` token list doesn't get expanded before
written out to PDF, we expand it using the assignment in `\edef` trick. The
token list gets expanded, but the assignment is not made until it reaches
main processor when the temporary control sequence gets expanded.
\_cod
% pdfpagattr managament (default for all pages vs current page override)
\_def\.pageattributes{{Trans}{Dur}{Rotate}{AA}}
\_def\.initpageattributes{%
% add hook for setting primitive \pdfpageattr
\_addto\_begoutput{\_edef\.tmp{\_pdfpageattr={\.pdfpageattributes}}\.tmp}%
% no need to do this twice
\_let\.initpageattributes=\_relax
}
\_nspublic \pageattributes \initpageattributes ;
\_doc
The user interface we want to expose has two parts:
\begitems
* setting the page attribute for just this one page (\`\.pdfcurrentpageattr`),
* setting the default attribute (used when current page value is not set)
(\`\.pdfdefaultpageattr`).
\enditems
The first one of course brings in the typical \TeX/ problem of knowing the
page where something occurs. As always, the page number contained in
`\gpageno` during processing of said content may of course not actually be
the number of the page where the content ends up! Hence, we need to note the
page number with a delayed write, using `\.setpageof` and later `\.pageof`.
The different settings of page attributes should have distinct names, we use
the \`\.pageattrcount` counter for this.
\_cod
\_newcount\.pageattrcount
\_def\.pdfcurrentpageattr#1#2{\.initpageattributes
\_incr\.pageattrcount
\.setpageof{pageattr:\_the\.pageattrcount}%
\.sxdef{pdfpgattr:\.pageof{pageattr:\_the\.pageattrcount}:#1}{#2}%
}
\_def\.pdfdefaultpageattr#1#2{\.initpageattributes
\.sxdef{pdfpgattr:#1}{#2}%
}
\_doc
Finally, the macro \`\pdfpageattributes` takes care of setting generating the
contents of `\pdfpageattr`. For each attribute in `\pageattributes` it first
checks its current page value, only then the default value. If neither is
set, nothing is added.
\_cod
\_def\.pdfpageattributes{\_ea\.pdfpageattributesA\.pageattributes\.end}
\_def\.pdfpageattributesA#1{\_ifx\.end#1\_else
% use current page override or "default"
% don't emit anything if the value is empty
\.attrorempty{#1}{%
\.trycs{pdfpgattr:\_the\_gpageno:#1}{\.trycs{pdfpgattr:#1}{}}%
}%
\_ea\.pdfpageattributesA\_fi
}
\_doc
Each attributes then has two switches for the respective default and current
values. For defining a few of them a helper is introduced:\nl\indent
\`\.pdfpageattributesetters`` <attribute> \<default setter> \<current setter> {<value>}`,
\nl
where <attribute> is name of the attribute without the slash
(e.g. `MediaBox`), the two control sequences name the future user setters,
which will take single argument in brackets
(e.g. `\mediabox` and `\thismediabox`) and the <value> can use the
argument.
\_cod
\_def\.pdfpageattributesetters#1 #2#3#4{%
\.sdef{\_csstring#2}[##1]{\.pdfdefaultpageattr{#1}{#4}}%
\.sdef{\_csstring#3}[##1]{\.pdfcurrentpageattr{#1}{#4}}%
\_nspublic #2 #3 ;
}
\_doc
Some of the useful attributes are `/Rotate`, which rotates the pages visually
(can be set with \`\defaultpagerotate` and \`\pagerotate`), and the additional
actions (`/AA`, see section~\ref[actions-additional], set using
\`\defaultpageactions` \`\pageactions`).
\_cod
\.pdfpageattributesetters Rotate \defaultpagerotate \pagerotate {#1}
\.pdfpageattributesetters AA \defaultpageactions \pageactions {\.pdfaactions{#1}}
\_doc
\label[transitions]
\secc Transitions, page durations
There are predefined types of transitions, like `/Wipe`, `/Box`, `/Split`,
etc. Most have other customizible attributes~-- usually directions set in
different ways depending on the animation type at hand, but the most
important attribute is the duration of the animation. Parsing friendly user
notation in the form of
`[<animation type>:<duration>:<other raw attributes>]`, where fields from the
right may be omitted to produce the default value, is handled by
\`\.maketrans`. This macro is also used by transition actions
(see~\ref[actions-jump]). The defaults are simply those defined by PDF
standard (no transition, 1 second duration and the respective default
directions).
\_cod
\_def\.maketrans[#1]{\.maketransA#1:::\.end}
\_def\.maketransA#1:#2:#3:#4\.end{%
\.emptyor{#1}{<</S /\.nonempty \.attrorempty{D}{#2} #3>>}
}
\_doc
The attribute setters for transitions (\`\transitions`, \`\transition`) are a
simple wrappers. Similiar is the
setting of page duration in seconds after which PDF viewer automatically
advances to the next page (\`\defaultpageduration`, \`\pageduration`).
\_cod
\.pdfpageattributesetters Trans \transitions \transition {\.maketrans[#1]}
\.pdfpageattributesetters Dur \defaultpageduration \pageduration {#1}
\_doc
\sec Attachments and document level JavaScript
These don't have any last place to be in, so they are documented separately,
here. Attaching files using `/FileAttachment` annotations:
\begitems \style n
* is intended more towards viewers of the document for extra additions and
* doesn't work in the viewers as well as one would like.
\enditems
That is why instead embed files using normal `\filedef` and then allow them
to be added to the document level `/EmbeddedFiles` entry, which means they
will be shown in the user interface by PDF viewers. `/EmbeddedFiles` is a
document level name tree (contained inside `/Names` entry of `/Catalog`) that
maps names of files to their objects. Although we simplify matters by
constructing more of an array.
What works very similiarly is document level JavaScript. It is a name tree
within `/JavaScript` field. It maps names of JavaScript actions to their
object numbers. The names aren't very useful, but the actions have their
purpose. They are executed in turn after the document is opened. Hence they
can be used to predefine JavaScript functions in the global context, to be
used later within actions explicitly activated by the user.
The user level commands are \`\attach``[<name>]` (to attach a previously
`\filedef`'d name with fallback to embedding now if it is a valid path) and
\`\dljavascript``[<name>]{<script>}` (adds action that executes <script>
after document is opened, <name> is more or less meaningless).
Internally both commands construct lists of what ends up in the resulting name
array, i.e. pairs {\visiblesp `(<name>) <object number> 0 R `}. Intermediate
macros \`\.embeddedfiles` and \`\.dljavascripts` are used for this.
In the case of file attachments, nothing happens if file is defined and not
found by the fallback.
\_cod
% file attachment
\_def\.embeddedfiles{}
\_def\.attach[#1]{\.isfiledefined{\.name}\_iftrue
\.xaddto\.embeddedfiles{(#1) \.cs{filespec:#1} }\_fi
}
\_nspublic \attach ;
\_def\.dljavascripts{}
\_def\.dljavascript[#1]#2{%
\_immediate\_pdfobj{<< \.jsaction[js:{#2}] >>}%
\.xaddto\.dljavascripts{(#1) \_the\_pdflastobj \_space 0 R }%
}
\_nspublic \dljavascript ;
\_doc
Object creation, which is common to both, is handled by\nl\indent
\`\.makenamearray``<name tree name><name tree content>`.\nl
It doesn't do anything
for empty lists, to not bloat PDF files when this mechanism isn't used.
\_cod
\_def\.makenamearray#1#2{\_ifx#2\_empty\_else
\_immediate\_pdfobj {<< /Names [ #2 ] >>}%
\_pdfnames{/#1 \_the\_pdflastobj \_space 0 R }\_fi
}
\_doc
The lists themselves can only be written out to the PDF file at the very end
of the run. We use \OpTeX/'s `\_byehook`, which is run in `\_bye`. But `\bye`
itself may be predefined by the user, for example when using some of the
\OpTeX/ tricks. We just hope that user keeps `\_byehook`.
\_cod
\_addto\_byehook{%
\.makenamearray{EmbeddedFiles}\.embeddedfiles
\.makenamearray{JavaScript}\.dljavascripts
}
\_doc
\sec Viewer preferences
There are a few customizations of display (and other preferences of PDF
viewers) possible in the document catalog or its subdictionary
`/ViewerPreferences`. Most are not that useful. The interesting
ones are implemented by \`\fullscreen`, \`\showoutlines`, \`\showattached`.
They all set the page mode using \`\.setpagemode`. We don't handle respecting
the last setting (using \`\_byehook`). To prevent invalid PDF files, we set
`\.setpagemode` to `\_relax` after use.
\_cod
\_def\.setpagemode#1{\_pdfcatalog{/PageMode /#1}\_glet\.setpagemode=\_relax}
\_def\.fullscreen{\.setpagemode{FullScreen}}
\_def\.showoutlines{\.setpagemode{UseOutlines}}
\_def\.showattached{\.setpagemode{UseAttachments}}
\_nspublic \fullscreen \showoutlines \showattached ;
\_doc
Only the setting of duplex / double sided printing and display is in the
nested dictionary. It is handled by \`\duplexdisplay`. The simplistic version
does not handle more attributes in `/ViewerPreferences`. We also set the
meaning to `\_relax` to prevent more (erroneous) uses.
\_cod
\_def\.duplexdisplay{\_pdfcatalog{%
/PageLayout /TwoPageRight
/ViewerPreferences <<
/Duplex /DuplexFlipLongEdge
>>}%
\_glet\.duplexdisplay=\_relax
}
\_def\duplexdisplay{\.duplexdisplay}
\_doc
\sec Multimedia
PDF essentially allows insertion of different types of multimedia:
\begitems
* images,
* audio/video,
* 3D art.
\enditems
The first is pretty standard and handled normally by the engine (\LuaTeX).
Others are possible, but have to be done manually according to one of the
mechanisms specified by PDF standard:
\begitems
* Sounds (audio only),
* Movies (video and/or audio),
* Renditions (video and/or audio),
* 3D annotations (3D art),
* Rich Media (video and/or audio, 3D art)
\enditems
Sadly all these mechanisms are badly flawed, each in different ways. At least
we try to use the one that works in the viewers.
For audio/video \"Movies" are the simplest mechanism, but they have been
deprecated in PDF 2.0 and no longer work in Acrobat/Foxit (same for
\"Sounds").
\"Renditions" are complicated, partly dependant on JavaScript, but at least
supported by Acrobat, Foxit, Evince and Okular.
\"Rich media" annotations were designed for Flash. This use case is no longer possible
today, but the obscurities remain. They are unnecessiraly complicated, but can
be used without Flash too. Although the result is very plain for audio/video~--
no controls can be displayed and there are no associated actions.
\"3D annotations" are reasonably simple, but also flawed. They cannot reuse
embedded file as a source for 3D data. Hence it is better and more consistent
to use Rich Media for 3D annotations. It even has additional benefits, like
the possibility of using multiple initialization scripts.
In the end, this package exposes two user commands corresponding to two
mechanisms~-- first are Renditions (`\render`) for audio/video that works in most
browsers and Rich Media (`\RM`) mainly for 3D art, but also for audio/video
with limited possibilities.
Both mechanisms have an annotation at their core. Annotations is essentially
a rectangular area on page. The area corresponds to where the
multimedium will show up. After activating the area somehow (by user click,
or action) the multimedium will start playing. Before annotations the
rectangular area will show something that is called \"normal appearance".
This appearance is of type form XObject. Those are really similiar to pages~--
they have dimensions, contents made up of PDF graphics operators, \dots,
but they are reusable. Not that useful for annotations where we will need the
form only once, but nice anyways. pdf\TeX/ has primitives for creating them~--
`\pdfxform` and friends. They essentially do the same code like `\shipout`
does, but instead of page, they make this reusable object. One can then
either use this reusable object in another page/form, but we will indirectly
refer to it for the appearance.
Important aspect of annotations is that they are really only rectangular
areas on the page, but they are not really part of the page. They sort of sit
on another level and are not influenced by PDF graphic operators which make
the page. In pdf\TeX/ annotations are handled by {\em whatsit} nodes. While
most nodes map to known primitive \TeX/ concepts (like typeset characters,
boxes, rules, etc.) Whatsits are essentially commands for \TeX/ that are
delayed until page is being shipped out (written to PDF file). `\write`,
`\special`, and most pdf\TeX/ commands create whatsits. For annotationos this
is important, because this means that the engine only stores the information
about annotation that we specify, but creates it at due time, when it should
be written to PDF.
Because whatsits are essentially dimensionless and we want it to be a part of
normal \TeX/ typesetting material we create the annotation (whatsit) in
`\hbox`. This box will be otherwise empty, because the apperance of the
rectangular area is determined by the normal appearance field (`/N` in
`/AP`). We set the dimensions of the box to the dimensions of normal
appearance. Everything will line up nicely, because when processed, the
annotation will take dimensions from the box.
All of these concepts are implemented in:\nl\indent
\`\.boxedannot``[<type>:<name>]{<appearance>}{<special text>}{<annotation attributes>}`\nl
<type> is used to determine the annotation border (same principle as with
Link annotations, section~\ref[actions-link]), <name> will be used as the
annotation name (`/NM`), <special text> is used for influencing the
`\pdfannot` primitive, and <annotation attributes> will become the body of
the annotation.
\_cod
\_def\.boxedannot[#1:#2]#3#4#5{%
\_setbox0=\_hbox{#3}\_setbox2=\_null
\_ht2=\_ht0 \_wd2=\_wd0 \_dp2=\_dp0
\_immediate\_pdfxform0
% box with annotation both stretching to dimensions of appearance
\_hbox{\.setpageof{#1:#2}%
\_pdfannot #4 {#5
/AP <</N \_the\_pdflastxform \_space 0 R>>
\_pdfborder{#1}
/NM (#2)
/Contents (#1 '#2')
}%
\_copy2
}%
}
\_doc
There is another weird thing common to both multimedia mechanisms~--
the redefinition of `\.name`. It is initially
set by `\.secondoptdef` to <name>, but may be redefined by user supplied
`name` key-value parameter. This should be used when there are multiple uses
of the same content. Otherwise samely named annotations would be
indistinguishable both for PDF viewer and our handling of actions (which
would all refer only to the first instance).
To somewhat overcome this, trying to use the same <name> (within the same
type of annotaiton) will use dummy name from \`\.unnamedannotcount` (for
uniqueness). This means that <name> will always refer to the first instance.
\`\.redefinename` handles this.
\_cod
\_newcount\.unnamedannotcount
\_def\.redefinename#1{%
\.isdefined{#1:\.name}\_iftrue
\_incr\.unnamedannotcount
\_edef\.name{\_the\.unnamedannotcount}%
\_else
\_edef\.name{\_kv{name}}%
\_fi
}
\_doc
\label[mm-renditions]
\secc Renditions (audio/video)
There are three main types of PDF objects involved in the Renditions
(\"Multimedia") mechanism:
\begitems
* Screen annotations define the area for playing multimedia.
* Rendition objects define the multimedia to play.
* Rendition actions associate Rendition objects with Screen annotations.
\enditems
You can theoretically arbitrarily mix and match rendition objects and screen
annotations by invoking different actions. In practice Evince and Okular do
really simplistic parsing and don't fully support the actions fully. But by
keeping it simple it is possible to make it work almost the same in all
viewers that support renditions.
Different sources of audio/video should be possible. In fact all three file
specifications (embedded files, files specified by URL/path) could work.
Again in practice embedded file is the safest bet, that works in all viewers
that support renditions.
The user facing command is:\nl\indent
\`\render``[<name>][<optional key-value paramers>]{<horizontal material>}`\nl\noindent
<name> is the friendly name set using `\filedef` or file path if <name> isn't
`\filedef`d and is to be embedded. The key-value parameters in brackets
can be entirely omitted. They can influence the playback (except for `controls`
most are not well supported). Default values are taken from
`\.renderdefaults`.
`\render` doesn't do anything (except print warning) if file <name> isn't
defined and <name> isn't a path to file that can be embedded.
The first PDF object it defines is Rendition, which specifies information
about the multimedium (name, file specification, MIME type and options from
key-value parameters). Some of the fields are in `/BE` (\"best effort")
dictionaries. This is due to the very general design of Renditions, which
theoretically allows the PDF viewer to choose from multiple Renditions if
they know they can't support some of the requested features. But that is not
much useful in practice, so we just don't complicate it.
Next defined object is Screen annotation, which complicates thing by
requiring (`/P`) reference to the page where the annotation is (handled by
`\setpageof` and `\pageof` pair). Important field is `/A` which specifies
actions that shall be executed when the screen area is clicked. We let the
user change the action, but the sensible default of starting to play the
multimedium is used (and this is the only thing that works in some viewers
anyways). Additional actions `/AA` may be used to react to events like mouse
over or page open/close~-- the most probable use case is autoplay on page
open, for which shortcut of \`\renditionautoplay` is defined.
The code is slightly complicated by the fact, that actions need to reference
the Rendition and Screen objects. In the case of the action contained in
Screen annotation this essentialy involves a self reference. Hence it is
needed to first reserve an object number and later use it for the annotation.
Because the object numbers may also be needed by actions defined later, we need
to save them to `\_pdfextra_rendition:<name>` and `\_pdfextra_screen:<name>`
respectively, but also define aliases with empty names, so users can easily
reference the latest rendition.
\_cod
\.secondoptdef\.render#1{\.isfiledefined{\.name}\_iftrue\_bgroup
\_ea\_readkv\_ea{\_ea\.renderdefaults\_ea,\_the\_opt}%
\.colortorgbdef\.bgcolor{\_kv{background}}%
% rendition object ("media specifaction")
\_pdfobj {<</Type /Rendition
/S /MR
/N \.cs{filename:\.name}
/C <<%/Type /MediaClip
/S /MCD % subtype MediaClipData
/D \.cs{filespec:\.name}
/CT (\.cs{filemime:\.name})
/P << /TF (TEMPALWAYS) >> % allow creating temporary files
>>
/P <<%/Type /MediaPlayParams
/BE << /C \_kv{controls} /V \_kv{volume} /RC \_kv{repeat} >>
>>
/SP <<%/Type /MediaScreenParams
/BE << /O \_kv{opacity} /B [\.bgcolor] >>
>>
>>}\_pdfrefobj\_pdflastobj
\.redefinename{rendition}%
\.sxdef{rendition:\.name}{\_the\_pdflastobj}%
% screen annotation ("screen space allocation")
\_pdfannot reserveobjnum% "self" reference will be needed inside screen annot.
\.sxdef{screen:\.name}{\_the\_pdflastannot}%
% aliases to latest rendition/screen with empty name
\_global\.slet{rendition:}{rendition:\.name}%
\_global\.slet{screen:}{screen:\.name}%
\_edef\.action{\_kv{action}}\_edef\.aactions{\_kv{aactions}}%
\.boxedannot[rendition:\.name]{#1}{useobjnum\_the\_pdflastannot}{%
/Subtype /Screen
% reference to page of the rendition (\setpageof done by \.boxedannot)
% the spaces are weird, but \pdfpageref eats them
/P \_pdfpageref\.pageof{rendition:\.name} \_space 0 R
/A \_ea\.pdfaction\_ea[\.action]
/AA \_ea\.pdfaactions\_ea{\.aactions}
}%
\_egroup\_fi
}
\_nspublic \render ;
\_doc
Here are the defaults used for `\render`~-- \`\.renderdefaults`. Users can
redefine them all together or override as needed with key-value parameters.
The defaults correspond to values specified by PDF standard. Other values may
not be respected by all viewers.
\_cod
\_def\.renderdefaults{%
name=\.name,
controls=false,
volume=100,
repeat=1,
opacity=1.0,
background=1 1 1,
action=rendition::play,
aactions={},
}
\_doc
Most probable use of additional actions is to start auto-start playing of the
multimedium. For this purpose \`\renditionautoplay` is defined as a shorthand
for action to play the lastly defined rendition on page visible event.
\_cod
\_def\.renditionautoplay{{PV}{rendition::play}}
\_nspublic \renditionautoplay ;
\_doc
\seccc Rendition actions
Rendition actions unfortunately use cryptic symbolic numbers (`0`, `1`, `2`
and `3`) for actions that could be called `play`, `stop`, `pause` and
`resume` respectively. Except for these predefined actions (that use `/OP`)
running of JavaScript is possible using `/JS (<script>)` with potential
fallback to `/OP`. This is dangerous teritory, because support of the right
API in the viewer is very low. Although it is possible to define such action
type by:
\begtt
\.sdef{renditionaction:myaction}{/JS (app.alert("something useful");) /OP 0}
\endtt
The use of rendition action is:
\`\.renditionaction``[rendition:<name>:<action type>]`. Empty name refers to
last rendition, so e.g.`\.renditionaction``[rendition::pause]` is possible.
\_cod
\.sdef{renditionaction:play}{/OP 0}
\.sdef{renditionaction:stop}{/OP 1}
\.sdef{renditionaction:pause}{/OP 2}
\.sdef{renditionaction:resume}{/OP 3}
\_def\.renditionaction[#1:#2:#3]{/S /Rendition
\.cs{renditionaction:#3}
/R \.cs{rendition:#2} 0 R
/AN \.cs{screen:#2} 0 R%
}
\_doc
\secc Rich Media (3D/audio/video)
Some principles seen with Renditions (section~\ref[mm-renditions]) apply here
too. But additionally we deal with 3D specifics and unfortunate Flash
leftovers.
Unlike Renditions both page area and multimedium specifaction are handled in
a single annotation~-- the Rich Media annotation. The code is unfortunately
obscured due to the weird requirements, but this is essentially what we are
trying to create with \`\RM`:
\begtt
/Type /Annot
/Subtype /RichMedia
/RichMediaSettings <<
/Activation <<
/Condition /PV
/Scripts [ 14 0 R ]
>>
/Deactivation << /Condition /XD >>
>>
/RichMediaContent <<
/Assets << /Names [ (kladka.prc) 2 0 R (wireframe.js) 14 0 R ] >>
/Configurations [ <<
/Type /RichMediaConfiguration
/Subtype /3D
/Instances [ <<
/Type /RichMediaInstance
/Subtype /3D
/Asset 2 0 R
>> ]
>> ]
>>
\endtt
The activation/deactivation will be dealt with later. But we see that to
insert a simple 3D file, we have to pack it inside a file specification
(indirect reference to object `2 0 R`), then in \"instance", inside a
\"configuration" inside \"content". As if it wasn't enough the names
(normally contained in the file specification) have to be specified again in
`Assets` name tree that uselessly maps names to file specifications. Because
this is a 3D Rich Media annotation there are other files at play~--
initialization scripts. These are specified in `/Scripts` and are executed in
turn when the annotation is activated. Not shown is, that some
\"configurations" and \"instances" actually have to be specified indirectly.
If it wasn't for Flash we could do with something like:
\begtt
/Type /Annot
/Subtype /RichMedia
/Activation /PV
/Scripts [ 14 0 R ]
/Deactivation /XD
/Content 2 0 R
\endtt
Which contains equivalent information. But unfortunately here we are\dots
\_cod
\.secondoptdef\.RM#1{\.isfiledefined{\.name}\_iftrue
\_edef\.tmp{\.cs{filemime:\.name}}%
\_edef\.subtype{\_ea\.mimetormsubtype\_ea[\.tmp]\_space}%
\_ifx\.subtype\_space
\_opwarning{unknown rich media type for '\.name', ignored}\_else
\_bgroup
\_ea\_readkv\_ea{\_ea\.RMdefaults\_ea,\_the\_opt}%
% Instance that has the media file as an asset
\_pdfobj {<</Type /RichMediaInstance
/Subtype /\.subtype
/Asset \.cs{filespec:\.name}
>>}\_pdfrefobj\_pdflastobj
% Configuration with one single instance (the above)
\_pdfobj {<</Type /RichMediaConfiguration
/Subtype /\.subtype
/Instances [ \_the\_pdflastobj \_space 0 R ]
>>}\_pdfrefobj\_pdflastobj \_edef\.configuration{\_the\_pdflastobj}%
\_edef\.names{\.cs{filename:\.name} \.cs{filespec:\.name} }% initial asset
\.redefinename{rm}%
\_def\.scriptfilespecs{}%
\_edef\.views{\_kv{views}}\_edef\.scripts{\_kv{scripts}}%
\_ifx\.views\_empty \_edef\.views{\.name}\_fi
\_ea\.DDDscripts\_ea{\.scripts}%
% annotation in hbox
\.boxedannot[rm:\.name]{#1}{}{%
/Subtype /RichMedia
/RichMediaSettings <<
/Activation <<
/Condition \.cs{activation:\_kv{activation}}
\.emptyor{\.scriptfilespecs}{/Scripts [ \.nonempty ]}
/Presentation << /Toolbar \_kv{toolbar} \.RMpresentationextra >>
>>
/Deactivation << /Condition \.cs{deactivation:\_kv{deactivation}} >>
>>
/RichMediaContent <<
/Assets << /Names [ \.names ] >>
/Configurations [ \.configuration \_space 0 R ]
\.emptyor{\_ea\.DDDviews\_ea{\.views}}{/Views [ \.nonempty ]}
>>
}%
\.sxdef{rm:\.name}{\_the\_pdflastannot}%
\_global\.slet{rm:}{rm:\.name}%
\_egroup\_fi\_fi
}
\_nspublic \RM ;
\_doc
The code is similiar to `\render`, but we also ignore everything if we don't
recognize the type of media (`Video`, `Sound` or `3D`). For that we use a
simple mapping from MIME types with \`\.mimetormsubtype`. This means that
although we aim Rich Media mostly for 3D art it may also be used for Video
and Sound.
\_cod
\_def\.mimetormsubtype[#1/#2]{\.cs{rmtype:#1}}
\.sdef{rmtype:model}{3D}
\.sdef{rmtype:video}{Video}
\.sdef{rmtype:audio}{Sound}
\_doc
Then we also need to construct the weird name \"tree" (essentialy an array in
our case) and script array. \`\.DDDscripts` and \`\.DDDviews` do this.
Name tree is accumulated in `\.names`, and starts with the media file. After
that each script is added to \`\.names` and \`\.scriptfilespecs`. The scripts
are passed as a comma separated array. Ignoring initial spaces is done using
undelimited-delimited argument pair trick.
\_cod
\_def\.DDDscripts#1{\.DDDscriptsA#1,,,\.end}
\_def\.DDDscriptsA#1#2,{\_ifx,#1\_ea\.untilend\_else
\.isfiledefined{#1#2}\_iftrue%
\_addto\.scriptfilespecs{\.cs{filespec:#1#2} }%
\_addto\.names{\.cs{filename:#1#2} \.cs{filespec:#1#2} }%
\_fi
\_ea\.DDDscriptsA\_fi
}
\_doc
For 3D views we need to process yet another comma separated list, this time
with \`\.DDDviews`. The result has to be separated by spaces and we also
don't want to emit something if the specified view was invalid. Unfortunately
this is expansion only context, so we can't issue a warning.
As a user convenience, before `\.DDDview` is executed, view with the name of
`\.name` is tried instead of empty view array. This means that for simple 3D
art with one view, one can create view with the same name as the 3D object
and not have to specify anything. We also take the name only after it is
redefined from optional key-value parameters~-- this is so we can support
even the case of e.g. `screw` 3D model used twice, once with `name=screw1`,
another time with `name=screw2` (with the corresponding `screw1` and `screw2`
views). This is probably less useful, but\dots
\_cod
\_def\.DDDviews#1{\.DDDviewsA#1,,,\.end}
\_def\.DDDviewsA#1#2,{\_ifx,#1\_ea\.untilend\_else
\.isdefined{3dview:#1#2}\_iftrue
\_lastnamedcs\_space \_fi
\_ea\.DDDviewsA\_fi
}
\_doc
The activation/deactivation names are kind of cryptic, so we give them
descriptive names. Default is explicit (de)activation. Instead of `/PV` (page
visible) and `/PI` (page invisible) it would be possible to use \"page open"
and \"page close". These are slightly different in cases when more pages are
shown on screen at once, because only one page is \"open", while multiple are
\"visible".
\_cod
\.sdef{activation:explicit}{/XA}
\.sdef{activation:auto}{/PV}
\.sdef{deactivation:explicit}{/XD}
\.sdef{deactivation:auto}{/PI}
\_doc
Additional means of customization are here. \`\.RMdefaults` contains the
default key-value parameters. \`\.RMpresentationextra` can be used to set
more attributes in `/RichMediaPresentation` dictionary (although those are
more specific and not generally useful).
\_cod
\_def\.RMdefaults{%
name=\.name,
activation=explicit,
deactivation=explicit,
toolbar=true,
views=,
scripts=,
}
\_def\.RMpresentationextra{}
\_doc
For scripting using JavaScript actions one needs to access the 3D context of
the 3D / Rich Media annotation. This requires the page number. We can't use
`this.pageNum` from [TODO], because the script strictly doesn't have to be on
the same page. We use `\.pageof` (`\.setpageof` was done in `\.boxedannot`)
to retrieve the page number in next run. Also PDF indexes page numbers from
0. \`\DDDannot``{<name>}`. and \`\DDDcontext``{<name>}` allow this.
\_cod
\_def\.DDDannot#1{%
this.getAnnotRichMedia(\_the\_numexpr\.pageof{rm:#1}-1\_relax, '#1')%
}
\_def\.DDDcontext#1{\.DDDannot{#1}.context3D}
\_nspublic \DDDannot \DDDcontext ;
\_doc
\label[mm-3dviews]
\secc 3D views
This is the interesting part about 3D art. They can have a set of predefined
views~-- although a user may start from one, they can interactively change
all the aspects by dragging with mouse or messing with the settings shown by
right click menu.
There are several transformations that have to be done before it is possible
to display 3D scene on a computer screen:
\begitems \style n
* 3D transformation from the coordinate system of 3D artwork (\"model") to the \"world
coordinate system".
* 3D transformation from the world coordinate system to camera coordinate
system.
* projection to 2D (3D to 2D transformation).
\enditems
When talking about PDF, positive $x$ goes to the right, positive $y$ up, and
positive $z$ \"away" from us (\"into the page"). This means we are working
with a left handed coordinate system. In camera space, the camera sits at
$(0, 0, 0)$ facing towards positive $z$ with positive $x$ and $y$ going right
and up respectively. Projection (one way or another) discards the $z$
coordinate.
Although the transformations are not strictly linear, they are essentially
done using multiplication by {\em transformation matrices}. The matrix for
\"model to world" (or \"model") transformation is part of the 3D art file and can't
be changed. However, we can make it up, because we can fully control the
second transformation (\"world to camera" or \"view" transformation)~--
although we don't specify the \"world to camera" matrix but rather its
inverse, the \"camera to world" matrix (`/C2W`). This matrix has the $4 \times 4$
form, which also allows {\em linear transformation} and {\em translation}:
$$
M_{c2w} = \pmatrix{a & d & g & t_x \cr b & e & h & t_y \cr c & f & i & t_z \cr 0 & 0 & 0 & 1}
$$
Here we use the column major convention, which is also the order how we would
write the matrix to PDF file, where it is an array of 12 elements:
\begtt \catcode`\$=3
/C2W [$a$ $b$ $c$ $d$ $e$ $f$ $g$ $h$ $i$ $t_x$ $t_y$ $t_z$]
\endtt
In the rendering pipeline everything is transformed from world coordinates to
camera space coordinates. We can think about the process also in the other
way. Using $M_{c2w}$ we specify camera's position and orientation in the
world coordinate system. Due to how transformation using matrix
multiplication works, the first column in the $M_{c2w}$ matrix (vector $(a,
b, c)^T$) specifies how \"positive $x$ direcetion" (\"right") from camera
space ends up in world coordinate system. Similiarly for $(d, e, f)^T$ being
the image of positive $y$ (\"up") and $(g, h, i)^T$ being the image of
positive $z$ (\"forward"). The last column, $(t_x, t_y, t_z)^T$ represents
translation from camera space to world. Translation of origin (camera
position) will leave it in the point with coordinates $(t_x, t_y, t_z)$.
Because of these associations with the intuitive meanings of $x$,
$y$, $z$ in camera space we also sometimes call the vectors in the first
three columns of $M_{c2w}$ \"right", \"up" and \"forward" and the last one
\"eye":
$$
\vec{R} = \pmatrix{a \cr b \cr c}\!, \quad
\vec{U} = \pmatrix{d \cr e \cr f}\!, \quad
\vec{F} = \pmatrix{g \cr h \cr i}\!, \quad
\vec{E} = \pmatrix{t_x \cr t_y \cr t_z}\!.
$$
We usually want $\vec{R}$, $\vec{U}$ and $\vec{F}$ to form an orthonormal set
of vectors, i.e. all of unit length and each pair is orthogonal. The
orthoganility will come from the way we calculate them, but the normality has
to be ensured by normalizing the vectors after computing them, which will not
be explicitly written out in the following text. $\vec{E}$ is a positional,
not directional, vector and it's length will be preserved.
Now we only need a convenient way to calculate all four vectors. A wide spread
method is sometimes called \"look at". It essentially involves having two
points: \"eye" ($E$, position of the camera) and \"target" ($T$, the point
where the camera is pointing at). The camera position is already provided:
$$
\vec{E} = E
$$
From these two points alone we can easily calculate the forward vector, which
corresponds to the direction of the camera:
$$
\vec{F} = \overrightarrow{ET} = T - E
$$
When we now imagine the point $E$ and vector $\vec{F}$ looking towards $T$ we
can see that there is a degree of freedom~-- the camera can rotate about the
forward vector. There is no other way than to arbitrarily choose
either up or right vector. Usually we choose an arbitrary \"global up" vector
$U_G$, which will influence the general direction of the final up vector.
This is because we use it to calculate the right vector:
$$
\vec{R} = \vec{U}_G \times \vec{F}
$$
The cross product makes it so that:
\begitems \style n
* $\vec{R}$ is perpendicular to $\vec{F}$
* it is also perpendicular to global up vector ($\vec{U}_G$) which we used to
get rid of remaining degree of freedom.
\enditems
Now that we have two orthonormal vectors (with the normalization not being
explicit) we can calculate the remaining up vector:
$$
\vec{U} = \vec{F} \times \vec{R}
$$
The last mysterious part about the calculation are the cross products. They
are of course not commutitative, so why e.g. $\vec{U}_G \times \vec{F}$ and
not the other way around? This is because we have to preserve the relations
these vectors had as directions of positive axes of the original camera
space. There we had positive $x$ going right, positive $y$ up and positive
$z$ forward in a left handed coordinate system. This means that following
holds (according the left hand rule):
$$\eqalign{
\vec{R} &= \vec{U} \times \vec{F} \cr % j * k = i
\vec{U} &= \vec{F} \times \vec{R} \cr % k * i = j
\vec{F} &= \vec{R} \times \vec{U} \cr % i * j = k
}$$
The scheme has one flaw though. When the directions of global up vector
$\vec{U}_G$ and forward vector $\vec{F}$ are linearly dependent the computed
right vector will be $(0, 0, 0)$. Hence some handling of this special case is
needed.
The \"look at" method is essentially what is used in Alexander Grahn's
package movie15\fnote{\url{https://www.ctan.org/pkg/movie15}}. Although the
input aren't two points, but rather a \"center of orbit" point ($COO$, our
\"target"), \"center of orbit to camera vector" ($\overrightarrow{C2C}$,
default is $(0, -1, 0)$) and distance of camera from the center of orbit
($ROO$). The value used for the arbitrary \"global up" vector is $(0, 0, 1)$.
When forward vector is $(0, 0, z)$, then global up is chosen to be $(0, -1,
0)$ or $(0, 1, 0)$ to handle the \"0 right vector" issue.
Because the movie15 method of providing the parameters is used in essentially
all packages that handle PDF 3D art (movie15, media9, rmannot, Con\TeX/t) we
also follow the suite.
\`\DDDview`[<view name>][<key-value parameters>] is the command for defining
3D views. These have to be saved into separate PDF objects anyways, using
this interface we allow their reuse. If <view name> is same as <name> of
`\RM` argument and no other views are specified <view name> view is
automatically used (see `\RM` for details).
Key-value parameters are not optional this time, because rarely one suffices
with default values~-- different 3D views are about customization. Handling
of them is not as straightforward as before. We initially read the key-value
parameters only to determine the `method` used for calculating the `/C2W`
matrix. Then we reread key-value parameters again, this time with also with
the default values for this particular method. Not that the general 3d views
details are changed, but the methods themselves have key-value parameters of
their own, and we support specifying them in this \"flat" way.
Additionally we allow the different methods used to compute `/C2W` to not be
expandable. Hence they are executed outside of expansion only context and are
fully processed~-- the text they add to 3D view PDF object is temporarily
stored in \`\.viewparams`.
The rest is simply setting sensible defaults (or user overrides) for
internal/external name of the view (`/IN` and `/XN`, one is used for
scripting, one is shown by the PDF viewer), background color, rendering mode,
and lighting. Cross sections and nodes are currently not supported, although
users can hook in their own code using `\.DDDviewextra`,
`\.DDDrendermodeextra` or `\.DDDprojectionextra`.
We have to be careful about setting rendering mode and lighting scheme,
because they normally fall back to the values specified in 3D art file, which
we can't access, so better not set them to anything if they are empty.
\_cod
\_def\.DDDview[#1][#2]{\_bgroup
\_readkv{\.DDDviewdefaults,#2}%
\_edef\.tmp{\.DDDviewdefaults,\.cs{3dview:\_kv{method}:defaults}}%
\_readkv{\.tmp,#2}%
\.colortorgbdef\.bgcolor{\_kv{background}}%
\.cs{3dview:\_kv{method}}% sets \.viewparams (/MS, /C2W, /CO)
\_pdfobj {<</Type /3DView
/XN (#1)
/IN (#1)
\.viewparams % /MS, /C2W, /CO
/P <<
\.cs{3dprojection:\_kv{projection}}
\.DDDprojectionextra
>>
/BG <<%/Type /3DBG
/Subtype /SC
/C [\.bgcolor]
>>
\.emptyor{\_kv{rendermode}}{%
/RM <<%/Type /3DRenderMode
/Subtype /\.nonempty
\.DDDrendermodeextra >> }%
\.emptyor{\_kv{lighting}}{%
/LS <<%/Type /3DLightingScheme
/Subtype /\.nonempty >> }%
>>}%
\_pdfrefobj\_pdflastobj
\.sxdef{3dview:#1}{\_the\_pdflastobj \_space 0 R}%
\_egroup
}
\_nspublic \DDDview ;
\_doc
\`\.DDDviewdefaults` stores default key-value parameters for 3D views. They
are mostly the PDF standard defaults or what movie15/media9 uses (for
compatibility).\`\.DDDviewextra`, \`\.DDDrendermodeextra` or
\`\.DDDprojectionextra` can be used by the users to hook themself into 3D
view object creation.
\_cod
\_def\.DDDviewdefaults{
projection=perspective,
scale=1,
ps=Min,
FOV=30,
background=1 1 1,
rendermode=,
lighting=,
method=media9,
}
\_def\.DDDprojectionextra{}
\_def\.DDDrendermodeextra{}
\_def\.DDDviewextra{}
\_doc
There are two different projection methods:
\begitems
* Orthographic: $z$ coordinate is simply thrown away, `scale` is used for scaling
the result. For technical parts where we want lines that are parallel stay
parallel in the view.
* Perspective: is the way human eye sees. `FOV` can be used to set field of
view. (`ps` parameter for additonal scaling to fit width/height is also
available, but the default is fine for casual users).
\enditems
\_cod
\.sdef{3dprojection:ortho}{/Subtype /O /OS \_kv{scale}}
\.sdef{3dprojection:perspective}{/Subtype /P /FOV \_kv{FOV} /PS /\_kv{ps}}
\_doc
We offer the possibility of setting`/C2W` matrix and `/CO` (distance from
camera to center of orbit) directly using `method=manual`.
\_cod
\.sdef{3dview:manual:defaults}{
matrix=1 0 0 0 1 0 0 0 1 0 0 0 ,
centeroforbit=0,
}
\.sdef{3dview:manual}{\_edef\.viewparams{
/MS /M
/C2W [\_kv{matrix}]
/CO \_kv{centeroforbit}
}}
\_doc
Another simple way of specifying camera position/orientation is to use a
named setting of U3D file using a U3D path with `method=u3d`.
\_cod
\.sdef{3dview:u3d:defaults}{
u3dpath=,
}
\.sdef{3dview:u3d}{%
\_pdfunidef\.tmp{\_kv{u3dpath}}%
\_edef\.viewparams{
/MS /U3D
/U3DPath \.tmp \_space
}}
\_doc
The most advanced method of setting `/C2W` matrix and `/CO` is
`method=media9`. It is thoroughly explained above, the few differences are
because the input values are not two points. Also for conciseness \"x", \"y"
and \"z" are used instead of right, up and forward. The calculations are
done in Lua, for simplicity.
We expect the user to supply the numbers in the form \"`1 2 3`", but in Lua we
need them comma separated (\"1, 2, 3"). \`\.luatriplet` does this. Just in
case the code is somehow adapted without ensuring that $x$ and $z$ are
orthonormal, we normalize also $y$ after the second cross product.
\_cod
\_def\.luatriplet#1 #2 #3 {#1, #2, #3}
\.sdef{3dview:media9:defaults}{%
roo=0,
coo=0 0 0,
c2c=0 -1 0,
}
\.sdef{3dview:media9}{\_edef\.coo{\_kv{coo}}\_edef\.c2c{\_kv{c2c}}\_edef\.viewparams{
/MS /M
/C2W [\_directlua{
local function normalize(x, y, z)
local len = math.sqrt(x*x + y*y + z*z)
if len ~= 0 then return x/len, y/len, z/len else return 0, 0, 0 end
end
local function cross(ux, uy, uz, vx, vy, vz)
return uy*vz - uz*vy, uz*vx - ux*vz, ux*vy - uy*vx
end
local function printmat(...)
local arr = table.pack(...)
for k, v in ipairs(arr) do
arr[k] = string.format("\_pcent.6f", v)
end
tex.print(table.concat(arr, " "))
end
local roo = \_kv{roo}
local coo_x, coo_y, coo_z = \_ea\.luatriplet\_expanded{\_kv{coo}}
local c2c_x, c2c_y, c2c_z = normalize(\_ea\.luatriplet\_expanded{\_kv{c2c}})
local eye_x, eye_y, eye_z = coo_x + c2c_x*roo, coo_y + c2c_y*roo, coo_z + c2c_z*roo
local z_x, z_y, z_z = -c2c_x, -c2c_y, -c2c_z
local up_x, up_y, up_z = 0, 0, 1
if math.abs(z_x) + math.abs(z_y) < 0.0000001 then % z_x == 0 and z_y == 0
if z_z < 0.0000001 then % z_z <= 0
up_x, up_y, up_z = 0, 1, 0
else
up_x, up_y, up_z = 0, -1, 0
end
end
local x_x, x_y, x_z = normalize(cross(up_x, up_y, up_z, z_x, z_y, z_z))
local y_x, y_y, y_z = normalize(cross(z_x, z_y, z_z, x_x, x_y, x_z))
local eye_x, eye_y, eye_z = coo_x - z_x*roo, coo_y - z_y*roo, coo_z - z_z*roo
printmat(x_x, x_y, x_z, y_x, y_y, y_z, z_x, z_y, z_z, eye_x, eye_y, eye_z)
}]
/CO \_kv{roo}
}}
\_doc
Last, but not least, is an action for setting the 3D view of a 3D/RM annotation
using an action. \`\.goto3dviewaction``[goto3dview:<name>:<view>]`. <name> is
name of the annotation which will be influenced. <view> is passed directly to
PDF. Therefore it can be either an index to the view array (starting at 0) or name
of view in parentheses~-- \"`(<view name>)`".
\_cod
\.sdef{goto3dviewaction}[#1:#2:#3]{/S /GoTo3DView
/TA \.cs{rm:#2} 0 R
/V #3
}
\_doc
\label[mime]
\sec MIME type database
This is the uninteresting MIME type database teased in section~\ref[files].
Ideally this would only be a subset of what IANA defines at
\url{https://www.iana.org/assignments/media-types/media-types.xhtml}.
But there are additions like `model/u3d` and `model/prc`, which don't
seem to be official, yet. Other \"unofficial" MIME types are taken from
Mozilla's \"common" lists:
\begitems
* \url{https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types}.
* \url{https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types}
\enditems
\`\.mimetype``{<extension>}{<MIME type>}` is a shortcut of mapping
<extension> to <MIME type>.
\_cod
\_def\.mimetype#1#2{\_sdef{_pdfextra_mimetype:#1}{#2}}
\.mimetype{js}{application/javascript}
\.mimetype{pdf}{application/pdf}
\.mimetype{prc}{model/prc}
\.mimetype{u3d}{model/u3d}
\.mimetype{wav}{audio/x-wav}
\.mimetype{mp3}{audio/mpeg}
\.mimetype{opus}{audio/opus}
\.mimetype{avi}{video/x-msvideo}
\.mimetype{mp4}{video/mp4}
\.mimetype{webm}{video/webm}
\_endnamespace
\_endcode
This is the technical documentation. It is intended for those who want to know
how this package works internally. Casual users shouldn't need to read this. But
if you would like to customize anything or perhaps just use some part of this
package, feel free to copy paste and use anything you want in \OpTeX/'s spirit.
This documentation is interleaved within the source itself, both are contained
in a single file, `pdfextra.opm` (according to \OpTeX/ conventions). The user
documentation is instead contained in `pdfextra-doc.tex`, which itself
`\input`'s the documented source file `pdfextra.opm` so that the user and
technical documentation is available in a single PDF file, `pdfextra-doc.pdf`.
|
