If you've got to import some data in a CAD software running on the Parasolid kernel, this format should be your first choice. Like with the ACIS-SAT format, the biggest strength of Parasolid-XT is its kernel nature. This greatly improves the applicability of the newer versions of the format. However, later versions of the format can have a mechanism for embedding a schema within a file, so that a properly constructed importer that hasn't yet seen the new schema can actually read the file and extract at least the data it knows how to interpret. Normally an importer of Parasolid-XT has to be presented with a schema to understand the files written in the version that the schema describes.

There are many schemas for Parasolid-XT files, roughly one for each version of the kernel. The set of data fields for each entity is fixed and is defined by the Parasolid-XT schema - a description of the data model of the format. The entities can have various data fields describing them, of numeric, boolean, string type, and also references to other entities. Parasolid-XT file consists of a list of entities, each assigned a number. The typical contents of a text Parasolid file top portion is a header, the bottom is populated with entities. 1), however, for separate files, it's much more popular than the binary version.įig. Unlike ACIS-SAT, text Parasolid-XT is not very human-readable and editable by hand (see Fig. Both versions contain the same data, but in different forms - x_t in space-separated text form, x_b in architecture-independent binary form.

The binary version normally has an x_b extension. The files in the text version have an x_t extension. Technically, XT in the format name actually refers to the text version of the format.

Parasolid-XT comes in two flavors - text and binary. The format's versioning is mainly aligned with the versioning of the kernel, although the core of the format has long been stable between versions. As is standard for any serious kernel, it has a persistence format, usually called Parasolid-XT, which is designed to transmit the B-Rep geometry of the model. It is at the heart of many popular CAD applications: SolidWorks, Solid Edge, Siemens NX, OnShape, and others. Parasolid is another popular geometric kernel like ACIS from the previous post in this series, its development began in the '80s and, currently, it's developed by Siemens.