JT (graphic format)
JT (Jupiter Tesselation) is an ISO standard graphic format for 3D data . JT can be selected as storage format by some 3D graphics programs .
format
The data model supports a wide variety of representations of CAD geometry:
- "Tessellated" triangular surface geometry, optionally in several resolutions ( levels of detail )
- "Exact" Brep geometry in the form of the older JT-BREPs, in the form of XT-BREPs (format of the Parasolid modeling kernel) or in the form of the highly compressive, but lossy LIBRA format.
JT is viewed as a particularly compact, easy-to-display and yet content-rich data format that also supports object and metadata (e.g. dimensions and tolerances). This makes it suitable for many applications in which CAD data is further processed (e.g. digital mock-up , as a replacement for drawings and for archiving ).
JT files have the standard extension .jt.
overview
JT is an industry-focused, neutral 3D data format that is used in many application processes after the geometry has been created, e.g. B. the modeling in Computer Aided Design Systems (CAD) is used instead of native CAD data formats.
This enables cooperation to be carried out independently of the geometry modeling system. B. to display and analyze 3D geometries and to make the complex function understandable on the 3D model. Additional information such as dimensions, tolerances, material, structure etc. are also made available in the JT - depending on the configuration and application.
JT has already established itself as the de facto standard compared to many competing formats in the industry and is now an ISO standard.
History and status
JT (Jupiter Tesselation) was specified in its first version in 1998 in cooperation with Hewlett-Packard and Engineering Animation, Inc. (EAI) and developed by EAI on the basis of the "Direct Model Toolkit". After the purchase of EAI by UGS (1999) and the subsequent acquisition of UGS by Siemens AG (2007), JT is now part of Siemens PLM Software .
JT has been continuously developed since 1997 (JT version 6.4) until today (2013) (JT version 10.0) according to customer requirements from the productive application and has its place between visualization formats such as VRML , IV etc. and formats that are used for Exchanges between modeling systems were designed, such as STEP, IGES , VDA-FS, DXF , conquered.
With the establishment of the “JT Open Initiative” in 2003 and the publication of the JT data format specification in 2007, the format was opened up to standardization. In addition to the work in the JT Open consortium on an international level, the spread of JT in Germany is also promoted by the Association of the Automotive Industry (VDA) and the ProSTEP iViP Association. In the context of working groups, use cases are examined - especially by representatives of the automotive industry - in productive customer processes.
At the end of August 2010, the New Work Item Proposal Ballot for JT was presented by ProSTEP iViP e. V. started, the first step in the ISO standardization process. The aim of the ProSTEP iViP association is to coordinate the standardization process of JT with the second major standardization project, STEP AP 242, which is ongoing in the association. It is planned to specify JT and AP 242 in such a way that STEP and JT can be used effectively together for data exchange.
In December 2012, JT was officially published as the world's first file format standard for the visualization and exchange of compressed and high-performance geometry data as an international industry standard in the first version (JT ISO V1.0): ISO 14306: 2012. This was the first time that a completely neutral, license-free specification was made available by JT.
At the beginning of 2013, work began on specifying the second version of the ISO standard JT 2.0. ISO / DIS 14306 V2 was adopted by ISO in November 2016. In the first half of 2017 [obsolete] the final publication as an international standard is to take place.
In order to provide industry with the functionalities and innovations it needs to work, ProSTEP iViP and VDA decided in mid-2015 to specify the JT Industrial Application Package (JTIAP). The JTIAP was then published in June 2016 as ProSTEP iViP Recommendation PSI 14. It is fully compatible with ISO 14306 (both ISO JT V1 and the planned V2) and with JT-Open-based implementations. The JTIAP comes up with a more powerful compression algorithm ( LZMA ), specifies XT B-Rep as the recommended representation of exact geometry and enables the neutral, license-free implementation of JT.
Content
At its core, the JT format is a scene graph with CAD-specific nodes and attributes support. Facet information (triangles) are stored using sophisticated compression techniques. It supports the mathematically exact geometry definition, the product structure, product and manufacturing information (PMI), visual attributes such as light, texture and shader as well as metadata. In addition to the JT format, the STEP AP 242 XML (ISO 10303-242: 2014) specified for these purposes, among other things, is used to transfer complex assemblies, configurations, kinematic structures, process information and much more. map and share with JT.
Applications and tools
The first goal of the user is to take over all relevant product data from the system that was used to create the geometry. So-called "translators" are used for this, which fill "segments" in JT format to a greater or lesser extent, depending on their configuration.
This information is then available in JT format and can be evaluated both interactively and automatically with other applications.
Applications for interactive visualization of the JTs (viewer, CAD systems) are often used for this purpose - e.g. E.g. in competition with 2D drawing - to make the nature of a geometry more understandable even to untrained users with the help of the 3D model. Extensive functionalities are available in such viewers in order to be able to visualize and analyze the contents of the JT format efficiently.
Numerous other software applications that are relevant for development and production can also read and process the JT format. For example, JT is used in numerous processes that follow geometry modeling. The JT format is often integrated into product lifecycle management -based processes in order to be able to efficiently handle and communicate changes (version and revision).
standardization
The International Organization for Standardization (ISO) has published JT as ISO 14306: 2012.
Summary
With over 4,800,000 users and over 50,000 customers, JT's potential does not seem to be exhausted yet. Reinforced by the ISO standardization, further application in the breadth and depth of JT's corporate processes will continue in the coming years.
See also
Individual evidence
- ↑ JT Patent Statement and Licensing Declaration. ISO TC184 / SC4, September 23, 2011, accessed on August 26, 2016 (English).
- ↑ ISO / DIS 14306 V2 - JT file format specification for 3D visualization. ISO, July 27, 2016, accessed August 26, 2016 .
- ↑ PSI 14-1: JT Industrial Application Package. ProSTEP iViP, June 30, 2016, accessed on August 26, 2016 (English).
- ↑ ISO 14306: 2012 - JT file format specification for 3D visualization. ISO, December 15, 2012, accessed August 26, 2016 .