ISO 14306:2017

Industrial automation systems and integration — JT file format specification for 3D visualization

ISO 14306:2017 defines the syntax and semantics of a file format for the 3D visualization and interrogation of lightweight geometry and product manufacturing information derived from CAD systems, using visualization software tools that do not need the full capability of a CAD system. ISO 14306:2017 has been adopted as a 3D visualization capability in addition to the ISO 10303 series. The file format supports the following information: · facet information (triangles), stored with geometry compression techniques · visual attributes such as lights, textures and materials · product manufacturing information, such as dimensions, tolerances and other attributes · boundary representation (b-rep) solid model shape representations. Several alternatives are available, including a representation based on the geometry standard defined in ISO 10303 · configuration representations · delivery methods such as asynchronous streaming of content ISO 14306:2017 does not specify the implementation of, or definition of a run-time architecture for viewing or processing of the file format.

Systèmes d'automatisation industrielle et intégration — Spécification de format de fichier JT pour visualisation 3D

General Information

• Status: Published
• Publication Date: 07-Dec-2017
• ICS: 25.040.40 - Industrial process measurement and control
• Technical Committee: ISO/TC 184/SC 4 - Industrial data
• Drafting Committee: ISO/TC 184/SC 4/JWG 16 - Joint ISO/TC 184/SC 4 - ISO/IEC JTC 1/SC 24 - ISO/TC 171/SC 2 WG: Formats for visualization and other derived forms of product data
• Current Stage: 9093 - International Standard confirmed
• Completion Date: 26-Mar-2023

Relations

• Revises: ISO 14306:2012 - Industrial automation systems and integration — JT file format specification for 3D visualization
• Effective Date: 22-Sep-2012

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 14306
Second edition
2017-11
Industrial automation systems
and integration — JT file format
specification for 3D visualization
Systèmes d'automatisation industrielle et intégration — Spécification
de format de fichier JT pour visualisation 3D
Reference number
ISO 14306:2017(E)
©
ISO 2017

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ISO 14306:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form
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ii © ISO 2017 – All rights reserved

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ISO 14306:2017(E)
Content

Content . iii
Foreword . xvi
Introduction . xvii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Abbreviated terms . 5
4 Notational conventions . 6
5 File Format . 14
5.1 File Structure . 14
5.1.1 File Header . 14
5.1.2 TOC Segment . 16
5.1.3 Data Segment . 17
5.2 Data Segments . 22
6 LSG Segment . 24
6.1 Graph Elements . 24
6.1.1 Node Elements . 25
6.1.2 Attribute Elements . 48
6.2 Property Atom Elements. 92
6.2.1 Base Property Atom Element . 92
6.2.2 String Property Atom Element . 93
6.2.3 Integer Property Atom Element . 94
6.2.4 Floating Point Property Atom Element . 94
6.2.5 JT Object Reference Property Atom Element. 95
6.2.6 Date Property Atom Element . 96
6.2.7 Late Loaded Property Atom Element . 97
6.2.8 Vector4f Property Atom Element . 99
6.3 Property Table . 99
6.3.1 Element Property Table . 100
7 Shape LOD Segment . 102
7.1 Shape LOD Element . 102
7.1.1 Base Shape LOD Element. 102
7.1.2 Vertex Shape LOD Element . 103
7.1.3 Tri-Strip Set Shape LOD Element . 118
7.1.4 Polyline Set Shape LOD Element . 118
7.1.5 Point Set Shape LOD Element . 119
7.1.6 Null Shape LOD Element . 120
7.2 Primitive Set Shape Element . 120
7.2.1 Lossless Compressed Primitive Set Data . 122
7.2.2 Lossy Quantized Primitive Set Data . 124
8 Geometry Segments . 129
8.1 STEP B-Rep Segment . 129
8.2 XT B-Rep Segment . 129
8.3 JT ULP Segment . 129
8.4 JT LWPA Segment . 129
8.5 Wireframe Segment . 129
8.6 JT B-Rep Element (deprecated) . 129
9 Meta Data Segment . 131
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ISO 14306:2017(E)
9.1 Property Proxy Meta Data Element . 131
9.1.1 Date Property Value . 133
9.2 PMI Manager Meta Data Element . 134
9.2.1 PMI Entities . 137
9.2.2 PMI Associations . 158
9.2.3 PMI User Attributes . 160
9.2.4 PMI String Table . 161
9.2.5 PMI Model Views . 161
9.2.6 Generic PMI Entities . 163
9.2.7 PMI CAD Tag Data . 169
9.2.8 PMI Polygon Data . 170
10 Data Compression and Encoding . 174
10.1 Common Compression Data Collection Formats . 174
10.1.1 Int32 Compressed Data Packet . 174
10.1.2 Int32 Compressed Data Packet Mk. 2 . 179
10.1.3 Float64 Compressed Data Packet . 185
10.1.4 Compressed Vertex Coordinate Array . 189
10.1.5 Compressed Vertex Normal Array . 190
10.1.6 Compressed Vertex Texture Coordinate Array . 192
10.1.7 Compressed Vertex Colour Array . 194
10.1.8 Compressed Vertex Flag Array . 196
10.1.9 Point Quantizer Data . 197
10.1.10 Texture Quantizer Data . 197
10.1.11 Colour Quantizer Data . 198
10.1.12 Uniform Quantizer Data . 200
10.1.13 Compressed Entity List for Non-Trivial Knot Vector . 200
10.1.14 Compressed Control Point Weights Data . 204
10.1.15 Compressed Curve Data . 205
10.1.16 Compressed CAD Tag Data . 208
10.2 Encoding Algorithms . 211
10.2.1 Uniform Data Quantization . 211
10.2.2 Bitlength CODEC . 211
10.2.3 Arithmetic CODEC . 212
10.2.4 Deering Normal CODEC . 217
10.3 zlib compression . 219
11 Common Data Conventions and Constructs . 220
11.1 Late-Loading Data . 220
11.2 TOC Segment Location . 220
11.3 Bit Fields. 220
11.4 Empty Field . 220
11.5 Local version numbers . 220
11.5.1 Version numbers . 221
11.6 Hash Value . 223
11.7 Scene graph construction . 223
11.8 Metadata Conventions . 224
11.8.1 CAD Properties . 224
11.8.2 PMI Properties . 228
11.8.3 Tessellation Properties . 324
11.8.4 Miscellaneous Properties . 325
11.9 LSG Attribute Accumulation Semantics . 326
11.10 LSG Part Structure . 327
11.11 Range LOD Node Alternative Rep Selection . 327
11.12 Brep Face Group Associations . 327
11.13 Handling of different states / variants in a JT file . 328
11.13.1 Reference Sets . 329
11.14 Watermarks . 329
11.14.1 Background . 329
11.14.2 Issue – Missing specification in the ISO . 330
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ISO 14306:2017(E)
11.14.3 Recommended Solution . 330
11.14.4 Issue – Protection of data . 332
12 Conformance requirements. 333
Annex A (informative) Object Type Identifiers . 334
Annex B (normative) STEP B-Rep . 338
B.1 STEP B-Rep Element . 338
B.1.1 STEP B-Rep Data . 338
B.1.2 STEP schema . 339
B.1.3 STEP format . 339
B.1.4 STEP external element reference in ISO 10303-21 . 339
Annex C (normative) STEP schema . 341
Annex D (informative) Coding Algorithms – An Implementation . 414
D.1 Common classes . 414
D.1.1 CntxEntry class . 414
D.1.2 CntxEntryBase2 class . 414
D.1.3 ProbabilityContext class. 415
D.1.4 ProbContex2 class . 416
D.1.5 CodecDriver class . 419
D.1.6 CodecDriver2 class . 422
D.2 Bitlength decoding classes . 426
D.2.1 BitLengthCodec class . 426
D.2.2 BitLengthCodec2 class . 430
D.3 Arithmetic decoding classes . 438
D.3.1 ArithmeticProbabilityRange class . 438
D.3.2 ArithmeticCodec class . 438
D.3.3 ArithmeticCodec2 class . 442
D.4 Deering Normal decoding classes . 446
D.4.1 DeeringNormalLookupTable class . 446
D.4.2 DeeringNormalCodec class . 448
Annex E (informative) Hashing – An Implementation . 451
Annex F (informative) Polygon Mesh Topology Coder . 454
F.1 DualVFMesh . 455
F.2 Topology Decoder . 461
F.2.1 MeshCoderDriver class . 461
F.2.2 MeshCodec class . 464
F.2.3 MeshDecoder class . 470
Annex G (informative)  XT B- Rep segment . 473
G.1 XT B-Rep Element . 473
G.1.1 XT B-Rep Data . 474
G.2 Procedural Geometry . 474
G.2.1 Background . 474
G.2.2 Issue . 474
G.2.3 Recommended Solution . 476
G.3 Non-Manifold Bodies . 476
G.3.1 Background . 476
G.3.2 Issue . 477
G.3.3 Recommended Solution . 477
Annex H (informative)  XT B- Rep data segment. 478
H.1 Introduction to the XT B- Rep data segment . 478
H.2 Logical Layout . 478
H.2.1 Schema . 479
H.2.2 Embedded schemas . 479
H.2.3 Field types . 480
H.2.4 Variable-length nodes . 481
H.2.5 Unresolved indices . 481
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ISO 14306:2017(E)
H.3 Physical Layout . 481
H.3.1 Binary . 481
H.4 Model Structure . 482
H.4.1 Topology. 482
H.4.2 General points . 483
H.4.3 Entity definitions . 483
H.4.4 Entity matrix . 487
H.4.5 Representation of manifold bodies . 487
H.5 Schema Definition . 489
H.5.1 Underlying types . 489
H.5.2 Geometry . 489
H.5.3 Topology. 521
H.5.4 Associated Data . 534
H.6 Node Types . 545
H.7 Node Classes . 547
H.8 System Attribute Definitions . 547
H.8.1 Hatching Attributes . 547
H.8.2 Density Attributes . 549
H.8.3 Region . 551
H.8.4 Colour . 551
H.8.5 Reflectivity . 551
H.8.6 Translucency . 552
H.8.7 Name . 552
H.8.8 Incremental faceting . 552
H.8.9 Transparency . 552
H.8.10 Non-mergeable edges . 553
H.8.11 Group merge behaviour . 553
H.8.12 Unicode name . 553
H.8.13 Monikers . 553
Annex I (informative) PMI Data Segment . 559
Annex J (informative) Mapping table from ISO 10303-42 to XT B-Rep . 560
J.1 Wireframe Geometry . 560
J.2 Surfaces without topology . 560
J.3 Shapes represented by wireframe models with topology . 561
J.4 Manifold Surfaces with Topology . 561
J.5 Advanced boundary representation solids . 563
J.5.1 Color . 564
J.5.2 Name . 565
J.5.3 Wireframe style . 565
J.5.4 Visibility . 566
Annex K (informative) JT B-rep Segment . 567
K.1 JT B-Rep Element . 567
K.1.1 Topological Entity Counts . 569
K.1.2 Geometric Entity Counts . 570
K.1.3 Topology Data . 571
K.1.4 Geometric Data . 580
K.1.5 Topological Entity Tag Counters . 589
K.1.6 B-Rep CAD Tag Data . 591
Annex L (informative) Wireframe Segment . 592
L.1 Wireframe Rep Element . 592
L.1.1 Wireframe MCS Curves Geometric Data . 594
L.1.2 Wireframe Rep CAD Tag Data . 594
Annex M (informative) JT ULP Segment . 596
M.1 JT ULP Element . 596
M.1.1 Topology Data . 598
M.1.2 Geometric Data . 615
M.1.3 Material Attribute Element Properties . 637
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ISO 14306:2017(E)
M.1.4 Information Recovery . 638
M.1.5 Non-Manifold Bodies .
...