ISO/IEC 8632-1:1992

ISO/IEC
INTERNATIONAL
STANDARD 86324
Second edi tian
1992-l o-01
e-e-_- -pl_-----------Y -.-------
_ __---_- -_-. - .- -_ -. - ---- ----_ ---_
_ __. _-. .______-_ I ____ __ ___ ___________._-. -___ ____. _ -__._- - _._, _. _ ._-_ . . _--._ _-_-e.- -- --.c- - .--.--.-.-- _--
Information technology - Computer graphics -
Metafile for the storage and transfer of picture
description information -
Part 1:
Functional speckfication
Technologies de l’inforn7a tion - lnfogr-aphie --- AMaficl~ier de stockage
et de tr&sfert des informations de description d’imges --
Pariie I: Description fonctionnelle
Reference nutnber
ISCMEC 8632-1:1992(E)

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ISO/IEC 8632-l: 1992 (E)
CONTENTS
. . . 1
. . . . . . . . .
. . . . . . .
1 Scope . . . . . . .
2
. . l . . . . .
. . . . . . . . .
2 Normative references . . . . .
. . . 4
. . . l . . . . .
. . . . . * .
3 Definitions and abbreviations
. 4
. . . . . . . . .
. . . . . . . . *
3.1 Definitions . . . .
. 9
. . . . . . . . . . . .
. . . . . .
3.2 Abbreviations . . .
. * . . . . . . 10
. . . . . . . . . . .
4 Concepts . . . . . . .
. . . . . . . . 10
. . . . . . . . . . .
4.1 Introduction . . . .
. . . . . . . . 10
. . . . . . . . . .
4.2 Delimiter elements . . .
11
. . . . . . . .
. . . . . . . . .
4.3 Metafile descriptor elements . .
12
. . . . . . . .
IdentifiLation . . . . . . . . . . .
4.3.1
12 L
. . . . . . . . . . .
Functional capab& . . . . . . . .
4.3.2
. .
. . . . . . . . . . 16
Default metafile state . . . . . . .
4.3.3
. . . 16
. . . . . . . . . . .
Fonts and character sets e . . .
4.3.4
. . . 21
. . . . . . . . . . .
4.4 Picture descriptor elements . . . . .
21
. . . . . . . . . .
. . . . . . . .
4.4.1 Scaling mode o . .
21
. . . . . . . . . . 0
Colour selection mode . . . . . . .
4.4.2
. . . 21
. . . . . . . . . . . . .
4.4.3 Specification modes . . .
. . . . . . 22
. . . . . . . . . .
4.4.4 VDC extent . . . . . .
. . . . . . . 22
. . . . . . . . . . .
4.4.5 CGM tailoring . . .
. . . . . . . . 24
. . . . . . . . . .
4.4.6 Background colour
. . . . . . . . 24
. . . . . . . . . .
4.4.7 Device viewport control
. . . . . . 25
. . . . * . . . . . . .
4.4.8 Representations . .
. . . . . 25
. . . . . . . . . . . . .
4.4.9 Definable attributes .
. . . . . . . . 25
4.5 Control elements . . . . . . . . . . .
. . . . . . . . 25
4.51 VDC space and rang; . . . . . . . . . . .
. . . . . . . . 25
. . . . . . . . . .
4.52 Clipping . . . . .
. . . . 27
. . . . . . . . . . .
4.5.3 Save and restore primitive context
. . . . 27
. . . . . . . . . . .
4.5.4 Compound clipping and shielding
. . . . 30
4.5.5 Generalized text path . . . . . . . . . . . . . . .
. . * . . . . . 30
4.5.6 Mitre limit . . . . . . . . . . . . . .
. . . . . . l . 30
4.5.7 Transparent cell colour . . . . . . . . . .
0 ISO/IEC 1992
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
photocopyin g and microfilm, without permission in
means, electronic or mechanical, including
writing from the publisher.
lSO/IEC Copyright Office l Case postale 56 l CH-1211 Genkve 20 l Switzerland
Printed in Switzerland
11

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ISO/IEC 8632-l: 1992 (E)
. . . 31
. . . . . . . . . . .
. .
4.6 Graphical primitive elements . . .
. . . . . . . . . . . 33
. . . . .
4.6.1 Line elements . . . . .
. . . . . . . . . . . 35
. . . . .
4.6.2 Marker element . . . .
. . . . . . . . . . . 36
. . . . .
4.6.3 Text elements . m . . .
. . . . . . . . . 36
4.6.4 Filled-area elements . . . . . . . . . .
. . . . . . . . . . . . . . 38
. . . . .
4.6.5 Cell elements
. . . . . . . . . . . 41
4.6.6 Circular arc elements . . . . . . . .
. . . . . . . . . 41
. . . . . . .
4.6.7 Elliptical elements . . . .
. . . . . . . . . 42
. . . . . . .
4.6.8 Hyperbolic Arc Element . .
. . . . . . . . . 42
4.6.9 Parabolic arc element . . . . . . . . . .
. . . . . . . . . 46
4.6.10 Spline curve elements . . . . . . . . . .
. . . . . . . . . . . . 48
4.6.11 Closed figures . . . . . . . . .
. 54
. . . . . . . . . . . .
4.6.12 Symbol elements . . . . . . .
. . . . 55
. . . . . . . . . . .
.
4.7 Attribute elements . . . . . .
. . . 58
. . . . . . . .
. . . . .
4.7.1 Line attributes . . . . .
. . . 59
. . . . . . . .
. . . . .
4.7.2 Marker attributes . . . .
l . . . 61
. . . . . . .
. . . . .
4.7.3 Text attributes . . . . .
. . . . 85
. . . . . . . . . .
. .
4.7.4 Filled-area attributes . . .
. . . . 87
. . . . . .
4.7.5 SDecification modes and transformation of aspects
. . . . . 88
. . . . . . . .
.......
4.7.6 C&our attributes
. . . . . 90
. . . . . . . .
4.7.7 Pick identifier .
. . . . . 90
. . . . . . . .
4.7.8 Compound text path .
. . . 91
. . . . . . . . . .
4.7.9 Symbol Attributes .
. . . . . 93
. . . . . . . .
4.8 Escape elements .
. . . . . l . 93
. . . . . .
4.9 External elements .
. . . l . . . 93
. . . . . .
4.10 Segment elements .
. . . . . . . 93
. . . . . .
4.10.1 Introduction .
. . . . . . . . 94
.... . . . l .
4.10.2 Local and global segments
. . . . . . . . . 95
. . . . . .
4.10.3 Delimiting and naming segments
. . . . . . . 95
....... . . . . . .
4.10.4 Segment attributes
. . . . . . . . . 96
... . . . .
4.105 Copy segment and inheritance
. . . . . . . . . 101
.......... . . . .
4.11 Metafile states
. . . . . . . . . . 112
........... . . .
4.12 Registration
. . . . . . 115
...... . . . . . . .
5 Abstract specification of elements
. . . . . . . . 115
........... . . . . .
5.1 Introduction
. . . . . 119
......... . . . . . . . .
5.2 Delimiter elements
. . . . . . . . . 119
5.2.1 BEGIN METAFILE . . . . .
. . . . . . . . . . . . . 119
5.2.2 END METAFILE .
. . . . . . . . . . . . . 119
5.2.3 BEGIN PICTURE .
. . . 120
.... . . . . . . . l . .
5.2.4 BEGINPICTURE BODY
. . . . . 121
. . . . . . . .
5.2.5 END PICTURE
. . . 121
............. . . . . . . . . . .
5.2.6 BEGIN SEGMENT
. . . . . . . . 121
....... . . . . .
5.2.7 END SEGMENT
. . . . . . . . . . . 122
5.2.8 BEGIN FIGURE . . .
. 122
. . . . . . . . . . . . . .
5.2.9 END FIGURE .
. . 122
. . . . . . . . . . . . .
5.2.10 BEGIN PROTECTION REGION’
. 123
... . . . . . . . . . . . .
5.2.11 END PROTECTION REGION
.
.... . . . . . . . . . . . . 123
5.2.12 BEGIN COMPOUNDLINE
.
. . . . . . . . . . . . . 123
5.2.13 END COMPOUND LINE
. 124
. . . . . . . . . . . . .
5.2.14 BEGIN COMPOUND TEXT PATH l
. . . 1’4 L
. . . . . . . . . .
5.2.15 END COMPOUND TEXT PATH . .
. . . . . 124
..... . . . . . . . .
5.2.16 BEGINTILE ARRAY
. . . . . 125
...... . . . . . . . .
52.17 END TILE ARRAY
. . .
111

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ISO/IEC 8632-l: 1992 (E)
. . . . . . . . 127
5.3 Metafile descriptor elements . . . . . . . . . . .
. . . . . . 127
5.3.1 METAFILE VERSION . . . . . . . . . .
. . . . . . 127
5.3.2 METAFILE DESCRIPTIbN l . . . . . . . . . .
. . . . . . . 127
5.3.3 VDCTYPE . . . . . . . . . . . . . . .
. . . . 128
5.3.4 INTEGER PRECISION . . . . . . . . . . . . . .
. . . . 128
5.3.5 REAL PRECISION . . . . . . . . . . . . . . .
. . . . 128
5.3.6 INDEXPRECISION . . . . . . . . . . . . . . .
. . . . 128
5.3.7 COLOUR PRECISION . . . . . . . . . . . .
. . . 129
5.3.8 COLOUR INDEX PRECISION . . . . . . . . . . . . .
. . . . 129
MAXIMUM COLOUR INDEX . . . . . . . . . . . .
5.3.9
. . . . . . 129
5.3.10 COLOUR VALUE EXTENT . . . . . . . . . .
. . . 130
5.3.11 METAFILE ELEMENT LIST . . . . . . . . . . . . .
. . . . . . e . . . . . 131
5.3.12 METAFILE DEFAULTS REPLACEMENT
. . . . . . . . . . . . . 132
5.3.13 FONT LIST . . . . . . . . .
CHARACTER SET LIST . . . . . . . . . . . . . 132
5.3.14
. . . . . . . . . . . . . 133
5.3.15 CHARACTER CODING A&ObN&
. . . . . . . . . . . . . . . 134
5.3.16 NAMEPRECISION . . . .
MAXIMUM VDC EXTENT . . . . . . . . . . . . . . . . . 134
5.3.17
. 134
5.3.18 SEGMENT PRIORITY EXTENT . . . . . . . . . . . . . .
. . 135
5.3.19 COLOUR MODEL . . . . . . . . . . . . . . .
. . . . . 135
5.3.20 COLOUR CALIBRAT;ON . . . . . . . . . . . .
. . . . . 137
5.3.21 FONTPROPERTIES . . . . . . . . . . . . . .
. . . 141
5.3.22 GLYPH MAPPING . . . . . . . . . . . . . .
. . . 142
5.3.23 SYMBOL LIBRARY I& . . . . . . . . . . . . . .
. . . . . . . . . * . . . 143
5.4 Picture descriptor elements . . . . . .
. . . . . . . . . . . 0 . . . 143
5.4.1 SCALINGMODE . . . . .
. . . . . . . . . . . . . . . 143
5.4.2 COLOUR SELECTION MODE
. . . . . 144
5.4.3 LINE WIDTH SPECIFICATION MODE . . . . . . . .
. . . . . . . . . . . . 144
5.4.4 MARKER SIZE SPECIFICATION MODE
EDGE WIDTH SPECIFICATION MODE . . . . . . . . . . . . 145
5.4.5
5.4.6 VDC EXTENT . . . . . . . . . . . . . . . . . . . . . 145
5.4.7 BACKGROUNDCOLOUR . . . . . . . . . . . . . . . . . 146
5.4.8 DEVICEVIEWPORT . . . . . . . . . . . . . . . . . . 146
5.4.9 DEVICE VIEWPORT SPECIFICATION MODE . . . . . . . . . . 147
5.4.10 DEVICE VIEWPORTMAPPING . . . . . . . . . . . . . . . 147
5.4.11 LINE REPRESENTATION . . . . . . . . . . . . . . . . . 148
5.4.12 MARKERREPRESENT-ATION . . . . . . . . . . . . . . . 148
. . . 149
5.4.13 TEXT REPRESENTATION . . . . . . . . . . . . . .
. . . . . . . . . . 150
5.4.14 FILL REPRESENTATION . . . . . . .
EDGE REPRESENTATION . . . . . . . . . . . . . . . . . 150
5.4.15
INTERIOR STYLE SPECIFICATION MODE . . . . . . . . . 151
5.4.16 . .
5.4.17 LINE AND EDGE TYPE DEFINITION . . . . . . . . . . . . 151
.
5.4.18 HATCH STYLE DEFINITION . . . . . . . . . . . . . 152
.
5.4.19 GEOMETRIC PATTERN DEFINIT;ON . . . . . . . . . . . . . 153
5.5 Control elements . . . . . . . . . . . . . . . . 155
5.5.1 vDc INTEGER ‘PREC&I;)N’ . . . . . . . . . . . . . . . . 155
5.5.2 VDC REAL PRECISION . . . . . . . . . . . . . . . . . 155
5.5.3 AUXILIARY COLOUR . . . . . . . . . . . . . . . . . . 155
5.5.4 TRANSPARENCY . . . . . . . . . . . . . . . . . . . 156
. 157
5.5.5 CLIP RECTANGLE . . . . . . . . . . . . . . . . . .
. . . . 157
5.5.6 CLIP INDICATOR . . . . . . . . . . . . . .
. 157
5.5.7 LINE CLIPPING MODE . . . . . . . . . . . . .
. 158
5.5.8 MARKER CLIPPING MODE’ . . . . : : . . . . . . . . .
iv

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ISO/IEC 8632-l: 1992 (E)
. 158
5.5.9 EDGE CLIPPINGMODE . . . . . . . . . . . . . . . .
. . . 158
5.5.10 NEW REGION . . . . . . . . . . . . . . . . . .
. l . . . 159
5.5.11 SAVE PRIMITIVE CONTEXT . . . . . . . . . . .
. . . . . . . . . 160
5.5.12 RESTORE PRIMITIVE CONTEXT . . . . .
. . . . . . . 160
5.5.13 PROTECTION REGION INDICATOR . . . . . .
. . . . . . . . 161
5.5.14 GENERALIZED TEXT PATH MODE . . . . .
. . . . . . . . . . . . . 161
5.5.15 MITRE LIMIT . . . . . . . .
. . . . . . . . . . . . . 161
5.5.16 TRANSPARENT CELL COLOUR . .
. e . . . . . . . . . . . 163
5.6 Graphical primitive elements . . . . . .
. . . . . . . . . . . . . 163
5.6.1 POLYLINE . . . . . . . . .
. . . . . . . . . . . . . 163
5.6.2 DISJOINT POLYLINE . . . . .
. . . 163
5.6.3 POLYMARKER . . . . . . . . . . . . . . . . .
. . . . . . 164
5.6.4 TEXT . . . . . . . . . . . . .
. . . . . . . . . . 165
5.6.5 RESTRI&ED TEXT . . . . . . . . .
. . . . . . . . . . . . . 166
5.6.6 APPENDTEXT . . . . . . .
. . . . . . . . . . . 167
5.6.7 POLYGON . . . . . . . . . . .
. . . . . . . . . . . . . 168
5.6.8 POLYGON SET . . . . . . .
. . . . . . . . . . . . . 171
5.6.9 CELL ARRAY . . . . . . . .
. . . . . . . . . . 173
5.6.10 GENERALIZED DRAWING PRIMITIVE (GDP)
. . 173
......... . . . . . . . . . .
5.6.11 RECTANGLE
. . . . . . . . . 174
........... . . .
5.6.12 CIRCLE
. . . . . . . . 174
5.6.13 CIRCULAR ARC 3 POINT . . . . .
. . . . . . . . . . 175
5.6.14 CIRCULAR ARC 3 POINT CLOSE . . . .
. . . . . . . . . . . . 177
5.6.15 CIRCULAR ARC CENTRE .
. . . . . . . . . . . . 177
5.6.16 CIRCULAR ARC CENTRE CLOSE . .
....... . . . . . . . . . . . . 178
5.6.17 ELLIPSE
. . . . . . . . . . . 179
5.6.18 ELLIPTICAL’ARC’ . l
. . . . . . . . . 180
5.6.19 ELLIPTICAL ARC CL&E . . . .
. . * . . . . . . . . . 181
5.6.20 CIRCULAR ARC CENTRE REVERSED .
...... . . . . . . . . . . . . 181
5.6.2 1 CONNECTING EDGE
. . . . 182
....... . . . . . . . .
5.6.22 HYPERBOLIC ARC
. . . . . 182
5.6.23 PARABOLIC ARC . . . . . . . .
. . . . . . . . . . . . 183
5.6.24 NON-UNIFORM B-SPLIl?k l
.
5.6.25 NON-UNIFORM RATIONAL B-bPLIl& l . . . . . . . . . . . 183
. .
5.6.26 POLYBEZIER . . . . . . . . . . . 184
. . . . 185
5.6.27 POLYSYMBOL . . . . . . . . .
. . . . . . . 185
5.6.28 BITONAL TILE . . . . . .
. . . l . . . . 187
5.6.29 TILE . . . . .
.......... . . . . . . . . . . . 190
5.7 Attribute elements .
. . . . . . . . . 190
5.7.1 LINE BUNDLE INDEX . . . .
. . . . . . . . . . . 190
5.7.2 LINE TYPE . .
......... . . . . . . . . . . 191
5.7.3 LINE WIDTH . .
.
.... . . . . . . . . . . . 192
5.7.4 LINE COLOUR
. . . 192
.... . . . . . . . . .
5.7.5 MARKERBUNDLEINDEX’
........ . . . . . . . . . 192
5.7.6 MARKER TYPE l . .
. .
....... . . . . . . . 193
5.7.7 MARKER SIZE . . .
. . .
. . . . . . 194
5.7.8 MARKER COLOUI; . . .
. . . .
5.7.9 TEXT BUNDLE INDEk . . . . . . . . 194
.
. . . . .
5.7.10 TEXTFONT INDEX . . . . . . . . 195
. . . . . . . 195
5.7.11 TEXT PRECISION . . . . . .
. . . . . . . 196
5.7.12 CHARACTER EXPANSION FA;CT~R’ . . . . . .
. . . . . . . 196
5.7.13 CHARACTER SPACING . . . . . .
. . . . . . . 197
5.7.14 TEXT COLOUR . . . . . .
V

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ISO/IEC 8632-l: 1992 (E)
. . . . . . . . . . 197
5.7.15 CHARACTERHEIGHT . . . . . . . .
. . . . . . . . . . . . 198
5.7.16 CHARACTERORIENTATION . . .
. . . . . . . . . . . . . . . . . . . 199
5.7.17 TEXT PATH
. . . . . . . . . . . . . . . . . 199
5.7.18 TEXT ALIGNMENT
. . . . . . . . . . . . 200
5.7.19 CHARACTER SET INDEX
. . . . . . . . . . . . 200
5.7.20 ALTERNATE CHARACTER’SE;. IND’EX’
201
. . . . . . . . . . . . . .
5.7.21 FILLBUNDLEINDEX . . .
. . 201
INTERIORSTYLE . . . . . . . . . . . . . . . .
5.7.22
. . . . . . . . . 202
5.7.23 FILLCOLOUR . . . . . . . . . .
. . . . . . . 202
5.7.24 HATCHINDEX . . . . . . . . . . . .
. . . . . . . . . . . . . . . 203
5.7.25 PATTERN INDEX . .
. . . . . . . . . . . . . 204
EDGEBUNDLEINDEX . . . .
5.7.26
. . . . . . . . . . . . . 204
EDGETYPE . . . . . . .
5.7.27
. . . . . . . . . . . . . . 205
EDGE WIDTH . . . . . .
5.7.28
. . . . . . . . . . . . . . 205
5.7.29 EDGECOLOUR . . . . .
.
. . . . . . . . . . . . . . . 206
5.7.30 EDGE VISIBILITY
. . . . 206
. . . . . . . . l .
5.7.31 FILLREFERENCEPOiNi’ . .
. . . . . 207
PATTERNTABLE . . . . . . . . . . . . .
5.7.32
. . . . . 207
PATTERNSIZE . . . . . . . . . . . . . .
5.7.33
. . . . . . . . 208
COLOURTABLE . . . . . . . . . . .
5.7.34
. . . . . . 209
ASPECT SOURCEFLAGS . . . . . . . . . .
5.7.35
. . . . . . . . 210
5.7.36 PICKIDENTIFIER . . . . . . . . . .
. . . . . . . . . . . . . . 210
5.7.37 LINE CAP . . . . . . .
. . 211
. . . . . . . . . . . .
5.7.38 LINE JOIN . . . . . . .
. . . . . 211
LINE TYPE CONTINUATION . . . . . . . . . .
5.7.39
. . 212
LINE TYPE INITIAL OFFSET . . . . . . . . . . . . .
5.7.40
. . 212
TEXTSCORETYPE . . . . . . . . . . . . . . . .
5.7.41
. . . . . 213
5.742 RESTRICTEDTEXTTYPE . . . . . . . . . . .
. . . . . . . . . . 214
5.7.43 INTERPOLATED INTERIOR . . . . .
. . . . . . . . . . 215
5.7.44 EDGE CAP . . . . . . . . . . .
. . . . . . . . . . . . . 216
5.7.45 EDGE JOIN .
. . . . . 216
5.7.46 EDGE TYPE CONTINUATION l . . . . . . . . .
. . . . . . . . . 217
5.7.47 EDGE TYPE INITIAL OFFSET . . . . .
. . . . . . . . . . . 217
5.7.48 SYMBOL LIBRARY INDEX . . . .
. . . . . . . . . . . . . . 218
5.7.49 SYMBOLCOLOUR . . . .
5.7.50 SYMBOL SIZE . . . . . . . . . . . . . . . . 218
5.7.5 1 SYMBOL 0RIENTAT;ON . . . . . . . . . . . . . . . . 219
5.8 Escape elements . . . . . . . . . . . . . . l . . . . . . . 220
5.8.1 ESCAPE . . . . . . . . . . . . . . . . . . . . . 220
5.9 External elements . . . . . . . . . . . . . . . . . . . . . 221
5.9.1 MESSAGE . . . . . . . . . . . . . . . . . . . 221
5.9.2 APPLICATION DATA. . . . . . . . . . . . . . . . . . 221
. . . . . . . . 222
5.10 Segment elements . . . . . . . . . . .
222
5.10.1 COPY SEGMENi’ . . . . . . . . . . . . . . . . .
5.10.2 INHERITANCE FILTER . . . . . 0 . . . . . . . . . . 222
224
5.10.3 CLIP INHERITANCE . . . . . . . . . . . . . .
224
5.10.4 SEGMENT TRANSFORMATION . . . . . . . . l . . . . .
. . . . 224
5.10.5 SEGMENT HIGHLIGHTING . . . . . . . . . .
5.10.6 SEGMENT DISPLAY PRIORITY . . . . . . . . . . 225
. . . .
5.10.7 SEGMENT PICK PRIORITY . . . . . . 225
. . . . . . . . .
6 Metafile defaults . . . . . . . . . . . 227
. . . . . . . . .
vi

---------------------- Page: 6 ----------------------
ISO/IEC 8632-l: 1992 (E)
. . . 232
. . . . .
.............
7 Conformance
. . 232
. . . . . .
.........
7.1 Forms of co~formark
. . 232
. . . . . .
.........
7.2 Functional conformance of meta&
. . . . . . . 232
.
7.3 Full conformance of metafiles .
. . . . . . 232
.......... . .
7.4 Conformance of other encodings
. . . . 233
. . . .
A Formal grammar of the functional specification of version 1 metafiles
l . . . . 233
. . .
................
A. 1 Introduction
. . . . . 233
. . . . . .
.........
A.2 Notation used
. . . . . 233
............ . . .
A.3 Detailed grammar’
. . . 233
..... . . . . .
....
A.3.1 Metafile struc&re
. . . 234
. . . . .
.........
A.3.2 Metafile descriptor elements
. . . 236
. . . . .
.........
A.3.3 Picture descriptor elements
. . . 236
. . . . .
...... . . ....
A.3.4 Control elements
. . . . 237
. . l .
...........
A.3.5 Graphical elements
l . . . 240
. . l . .
...........
A.3.6 Attribute elements
. . . . . 243
. . .
............
A.3.7 Escape elements
. . . . . . . 243
.
A.3.8 External elements .
. . . . . . . 244
.............. .
A.4 Terminal symbols
248
. . . . . . . .
B Formal Grammar of the functional specification of version 2 metafiles
. . . 248
. . . l .
................
B.l Introduction
. l . . . 248
... l . . . .
.........
B.2 Notation used
. . . . . . . 248
.
............
B .3 Detailed grammar’
. . . . . . . . 248
.........
B.3.1 Metafile struck-e
. . . . . . . . 249
.........
B .3.2 Metafile descriptor elemenk
. . . . . . . . 252
.........
B.3.3 Picture descriptor elements
. . . . . . . . . 254
...........
B.3.4 Control elements
. . 255
. . . . . .
...........
B .3.5 Graphical elements
. . 257
. . . . . .
............
B.3.6 Attribute elements
. . . . . 261
. . .
B.3.7 Closed figure element .
. . . . . 261
. . .
B .3.8 Escape elements .
. . . . . 262
. . .
B.3.9 External elements .
. . . . . . . 262
............ .
B .3.10 Segment elements
. . . . . . . . 264
..............
B.4 Terminal symbols
. . . . . 272
. . .
C Formal grammar of the functional specification of version 3 metafiles
. . . . . l 272
................ . .
C.1 Introduction
. . . . . . . 272
............. .
C.2 Definitions
. . . . . 272
...... .... . . .
C.2.1 Notatidn &ed
. . . . . . . 272
.......... .
C.2.2 Structured Data Records:
. . . . . . . . 273
..............
C.3 Detailed Grammar
. . . . . . . . 273
............
C.3.1 Metafile structure
. . . . . . . . 278
.........
C.3.2 Metafile descriptor elements
. . . . . 281
......... . . .
C.3.3 Picture descriptor elements
. . . l . . . 285
............ .
C.3.4 Control elements
. . . . . . . 286
........... .
C.3.5 Graphical elements
. . . . . . . . 289
............
C.3.6 Attribute elements
. 294
. . . . . . .
............
C.3.7 Escape elements
. 294
. . . . . . .
............
C.3.8 External elements
. . . . . . . . 294
............
C.3.9 I Segment elements
. . . . . . . . 297
..............
C.4 Terminal symbols
. . . . . . . 307
.
D Guidelines for metafile generators and interpreters . . . . . .
. . . . . 307
. . .
D. 1 Introduction . . . . . . . . . . . . . . . .
vii

---------------------- Page: 7 ----------------------
ISO/IEC 8632-l: 1992 (E)
. 307
D.2 Errors and degeneracies . . . . . . . . . . . . l . . . . . .
. . 308
. . . . . . . . . .
D.2.1 Syntax errors . . . . . . . . .
. . . . . . . . . . . . 308
D.2.2 Geometrically degenerate primitives . .
. 309
. . . . . . . . . . .
D.2.3 Mathematical singularities and ambiguities
. 309
. . . . . . . . . . . . .
D.3 General guidelines .
. 309
. . . . . . . . . . . . .
D.3.1 Indexes .
309
. . . . . . . . . . . . . .
D.3.2 Colour model .
312
. . . . . . . . . . . . . .
D.3.3 Order of metafile descriptor elements
. . . . . . . . . . 312
. . . . . .
D.3.4 Unsatisfied references . . .
. . . l . . . . . . . . . 312
. . . . .
D.4 Guidelines for element classes
. . . . . * 312
l . . . . l . . .
. .
D.4.1 Delimiter elements
. . . . . . 312
. . . . . . .
. . .
D.4.2 Metafile descriptor elemenk .
. . . . . . 312
. . . . . . . . .
.
D.4.3 Picture descriptor elements .
. . . . . . 313
. . . . . . . . .
.
D.4.4 Control elements . . . .
. . . . . 313
. . . . . . . . . .
D.4.5 Graphical primitive elements .
. . . . . . 316
. . . . . . . . . .
D.4.6 Attribute elements . . . .
. . . . . . . . 318
. . . . . . . .
D.4.7 Escape elements . . . .
318
. . . . . . . . . .
. . . . . .
D.4.8 External elements . . . .
. . . . . . . 318
. . . . . * . . .
D.4.9 Segment elements . . . .
. . . 320
. . . . . . . . . . .
. .
E Guidelines for private encodings . . .
. . . . . . . . . . 321
. . . . . .
F Reference models . . . . . . . .
. . . . 325
G Conversions between the CIEXYZ reference corour space and metafile colour spaces
. . . . . 325
Gl Introduction . . . . . . . . . . . . . . . . . . .
. . . . . 325
G’2 . Definitions . . . . . . . . . . . . . . . . . . .
. . . . . 325
G3 . CIELUV . . . . . . . . . . . . . . . . . . . .
. 325
. . . .
G.3.1 Conversion from the CIEXYZ reference colour space to CIELUV
. . 326
. . .
G.3.2 Conversion from CIELUV to the CIEXYZ reference colour space
. 327
. . . .
G4 . CIELAB . . . . . . . . . . . . . . . . . . . .
. 327
. . . .
G.4.1 Conversion from the CIEXYZ reference colour space to CIELAB
. . 328
. . .
G.4.2 Conversion from CIELAB to the CIEXYZ reference colour space
. 329
. . . l . .
RGB
G5 .
. . . . . . 329
G.5.1 Conversion frbm*the CIEXYZ*re fk,,,,‘,olour sphce.to kGi .
. 330
. . . .
G.5.2 Conversion from RGB to the CIEXYZ reference colour space . .
. . 331
. . .
G6 RGB-related . . . . . . . . . . . . . . . . . . .
. . . 331
. . .
G-7 . CMYK
. . . . 331
. .
G.7.1 Converkon fromC&YK to the &EXYZ refere’nce copout &a&
. . . . . 331
G.7.2 CMYK Calibration data . . . . . . . . . . . . .
. . . . . 332
G8 . Bibliography . . . . . . . . . . . . . . . . . . .
. . .
Vlll

---------------------- Page: 8 ----------------------
ISO/IEC 8632-l: 1992 (E)
Foreword
IS0 (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
IS0 or IEC participate in the development of International Standards through technical committees established
by the respective organization to deal with particular fields of technical activity. IS0 and IEC technical
committees collaborate in fields of mutual interest. Other international organizations, governmental and non-
governmental, in liaison with IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint technical committee, ISO/IEC
JTC 1, Draft International Standards adopted by the joint technical committee are circulated to national bodies
for voting. Publication as an International Standard requires approval by at least 75 % of the national bodies
casting a vote.
International Standard ISO/IEC 8632-l was prepared by Joint Technical Committee ISO/IEC JTC 1,
Information technology.
which has been technically
This second edition cancels and replaces the first edition (IS0 863291:1987),
revised.
ISO/IEC 8632 consists of the following parts, under the general title Information technology - Comyutel
graphics - IMetafile for the storage and transfer of picture description information :
Part I : Functional specification
Part 2: Character encoding
Part 3: Binary encoding
Fart 4: Clear text encoding
Annexes A, B, and C form an integral part of this part of ISO/IEC 8632. Annexes D, E, F and G are for
information only
ix

---------------------- Page: 9 ----------------------
ISO/IEC 8632-l: 1992 (E)
Introduction
0.1 Purpose
The Computer Graphics Metafile provides a file format suitable for the storage and retrieval of picture
information. The file format consists of a set of elements that can be used to describe pictures in a way that
is compatible between systems of different architectures and devices of differing capabilities and design.
This picture description includes the capability for describing static pictures. Static pictures are those
where elements which may lead to dynamic effects (for example those leading to regeneration) are prohi-
bited within the picture body.
0.2 Reasons for this International Standard
The main reasons for producing a stand ard corn puter graphics metafile are
to allow picture information to be stored in an organized way on a graphical software system;
a>
to facilitate transfer of picture information between different graphical software systems;
b)
to enable picture information to be transferred between graphical devices;
c>
to enable picture information to be transferred between different computer graphics installations.
d)
0.3 Design requirements
To reach these objectives, a number of design principles were adopted:
The metafile should provide a suitable set of elements for the transfer of a wide range of pictorial
a>
information.
The metafile should address the more usual and essential features found on graphical devices
b)
directly and should provide access to less common facilities via an escape mechanism.
The design of the metafile should not preclude extension of ISO/IEC 8632 at a later stage to cover
C)
facilities beyond those included in this version of the Standard. It should also not preclude further
extensions to support future standards.
The metafile should be usable from GKS (Graphical Kernel System - IS0 7942) with both
d)
metafile input and metafile output functions. It should include the capability to support IS0 7942
(GKS) static picture capture.
X

---------------------- Page: 10 ----------------------
ISO/IEC 8632-1: 1992 (E)
Introduction
Design requirements
ISO/IEC 8632 should address the needs of different applications that have conflicting require-
e)
ments for size of metafile, speed of generation and interpretation, readability, editability and ease
of transfer through different transport mechanisms.
0.4 Design criteria
The requirements of 0.3 were used to formulate the following criteria which were used to decide between
different design possibilities.
Completeness: In any area of ISO/IEC 8632, the functionality specified by ISO/IEC 8632 should
a>
be complete in itself.
Conciseness: Redundant elements or parameters should be avoided.
b)
Consistency: Contradictory elements should be avoided.
c)
Extensibility: The ability to add new elements and generality to ISO/IEC 8632 should not be pre-
d)
cluded.
Fidelity: The minimal results and characteristics of elements should be well defined.
e>
Implementability: An element should be able to be supported efficiently on most host systems
f)
and/or graphics hardware.
Orthogonality: The elements of the metafile should be independent of each other, or any depen-
s)
dencies should be structured and well defined.
Predictability: ISO/IEC 8632 should be such that the recommended or proper use of standard ele-
h)
ments guarantees the results of using a particular element.
Standard practice: Only those elements that reflect existing practice, that are necessary to support
existing practice, or that are necessary to support proposed standards should be standardized.
.
Usefulness: Functions should be powerful enough to perform useful tasks.
J)
Well-structured: The assumptions that elements make about each other should be minimized. An
k)
element should have a well-defined interface and a simply stated unconditional purpose. Mul-
tipurpose elements and side effects should be avoided.
0.5 Access to a metafile
The metafile has been designed so that, although its main usage is anticipated as being with completely
sequential access, non-sequential access is also possible. Once the basic environment of the metafile has
been established, individual pictures may be accessible if the medium, the encoding and the implementation
support this form of access.
0.6 Generation and interpretation of metafiles
The specific mechanisms of metafile generation and interpretation are not described by ISO/IEC 8632,
although it does describe the intended result of such interpretation. The basic set of metafile elements
includes a capability for the addition of application-dependent data, which do not have graphical meaning
and for which no intended interpretation results are described.
0.7 Distinction between formal specification and encodings
The functionality provided by the metafile is separated from the
...