SAT

Latest revision as of 17:43, 13 May 2009

Title(s): Standard ACIS Text (SAT)

Version ID: R19 (SP3)

Date released: 2009-03-19

Date: 1989-??-??

Creator(s): Charles Lang and Ian Braid; Three-Space Ltd.

Contributor(s): Spatial Corporation

Relationships:

• Previous Version(s): Romulus (1982)

• Contains: None

• Syntax Format(s): None

• Family Format(s): ACIS Format

Description: SAT is the ASCII version of a file used by the ACIS modeling system. It has a binary analog called SAB (Standard ACIS Binary).

The ACIS modeling system is currently maintained by the Spatial Corporation. The system allows 3D modeling, 3D model management, and 3D model visualization. The system also allows extensions that provide additional functionality. ACIS is used in a variety of industries, including CAD, CAM, CAE, AEC, animation, and shipbuilding. For more details on the ACIS modeling system, see this site.

History: The ACIS modeling system began life as Romulus, created by Ian Braid and Charles Lang in 1982. Romulus was the first commercial solid modeling kernel designed for integration into CAD systems and was licensed by several CAD software vendors, including HP and Siemens. In 1986, Three-Space Ltd. (founded by Braid and Lang) was retained by Spatial Technology (now known as Spatial Corporation) to create the ACIS modeling system.

In terms of the history of the file format, changes were (and continue to be) introduced with each new version of ACIS. The file specifies which version it was created for, so the format is backwards-compatible.

Though it is readable in plain text, the file format does not lend itself very well for editing. Objects represented through the file can be quite confusing. For example, if you wanted to create a cone, you need to provide some arguments to the cone entity, but what those arguments are is not very clear. This format should mainly be edited through the ACIS program.

Example(s): SAT Example 1 , SAT Example 2

Identifier: [[Identifier::[1]]]

Documentation: SAT Documentation

File Extensions: SAT

Applications:

• Native application(s): ACIS

• Interoperable applications: Applications with ACIS

Magic numbers: None

Format(s): The file is organized as follows:

• The header record consisting of various information, including:
  • The version number
  • The number of saved entities
  • The ID of the product that produced the file
  • The date that the file was produced on
  • Tolerance values of the application that produced the file
• Entity records. Each entity is an object in the ACIS system. For more info on entities, see [2].
• History records (if any)
• "End-of-ACIS-data" terminator

The header record should not be modified except by the program saving the file.

Rights: Proprietary License

Sustainability Factors:

• Standardization: File format specified by Spatial Corporation.

• Adoption: None

• • Licensing and patent claims: Patented by Spatial Corporation.

• Self-documentation: None.

• External dependencies: ACIS

• Technical protection considerations: None.

Typical use: CAD, CAM, CAE

File classification:

• Type {Binary, Text}: Text
• Raster data:
  • Raster data 2D:
    • Is Supported: false
    • Description: Only entities can be defined.
  • Raster data 3D:
    • Is Supported: false
    • Description: Only entities can be defined.
• Geometric representation:
  • Implicit representation:
    • Implicit surfaces:
      • Is Supported: false
      • Description: Surfaces can be defined by defining specific parameters for each surface (point, normal for plane; center, radius for sphere
    • Implicit curves:
      • Is Supported: false
      • Description: [[File Classification Implicit Curves - Description::Various types of curves can be defined by their parameters ([3]), but curves cannot be defined implicitly]]
    • Point set:
      • Is Supported: true
      • Description: A point is a type of entity
  • Mesh:
    • Manifold surface meshes:
      • Is Supported: true
      • Description: A mesh can be defined explicitly
    • Manifold volume meshes:
      • Is Supported: true
      • Description: A mesh can be defined explicitly
    • Non-manifold meshes:
      • Is Supported: true
      • Description: A mesh can be defined explicitly
  • Parametric representation:.
    • Parametric surfaces:
      • Is Supported: false
      • Description: Surfaces can be defined by their parameters, but not by parametric equations
    • Parametric curves:
      • Is Supported: true
      • Description: Parametric curves can be defined as entities
  • Contour sets:
    • Is Supported: false
    • Description: Not supported
  • NURBS:
    • Is Supported: true
    • Description: NURBS can be defined
• Multi-resolution models:
  • Is Supported: false
  • Description: The resolution is defined in the header of the file
• Dynamics:
  • Kinematics:
    • Is Supported: true
    • Description: Entities can be rotated
  • Assembly:
    • Is Supported: true
    • Description: An entity can be assembled from many other entities
  • Force(s):
    • Is Supported: false
    • Description: May be supported through extensions to the system
• Boundary representation
  • Manifold surface boundary representations:
    • Is Supported: true
    • Description: The boundary is made from a closed set of defined surfaces.
  • Manifold volume boundary representations:
    • Is Supported: true
    • Description: The boundary is made from a closed set of defined surfaces.
  • Non-manifold boundary representations:
    • Is Supported: true
    • Description: The boundary is made from a closed set of defined surfaces.
• Material transparency:
  • Is Supported: true
  • Description: Surfaces can be transparent

References:

• Spatial Corporation's product page for ACIS
• Documentation for ACIS
• Details on saving SAT file
• Details on Entities in ACIS system
• Tutorial page with two SAT files
• Details on SAT file format
• The wikipedia page for ACIS