ACIS Writer

ACIS
File Extension SAT, SAB
Supported Versions 5.0
Platforms
Tessellation N/A
B-rep Supported
PMI N/A

ACIS is a widely-used geometric modeling kernel that provides robust 3D modeling functionalities for various CAD, CAM, and CAE applications.

The ACIS file format stores 3D geometry data, including vertices, edges, faces, and bodies, using a precise and efficient representation.

This format is commonly used for interoperability between different CAD systems and for accurate geometric representation in engineering and design applications.

Our support for ACIS covers both reading and writing ACIS files on Windows, GNU/Linux, and macOS. HOOPS Exchange handles geometry in the following way:

  • B-rep: Suitable for downstream CAD applications that require exact geometry.
  • Tessellation: Can be exported when your workflows rely on visualization meshes.

How to Export to ACIS

To export a model to ACIS, use A3DAsmModelFileExportToAcisFile(). Customize the export using A3DRWParamsExportAcisData.

A3DRWParamsExportAcisData sParamsExportData;
A3D_INITIALIZE_DATA(A3DRWParamsExportAcisData, sParamsExportData);
// ... set export parameter options

A3DAsmModelFileExportToAcisFile(pModelFile, &sParamsExportData, "path/to/file.sat");

Assembly

ACIS does not support the concept of assemblies, so we flatten the assembly before exporting. All parts will appear as sibling parts, with transformations and coloring preserved to match the source data.

To understand and manipulate the model tree before export, see assembly traversal or the :doc:`Tree Traversal API <guide/tree_traversal>’.

Export to Buffer

Our ACIS writer provides additional methods to export data:

  • A3DAsmModelFileExportToAcisBuffer(): Writes a model file to a memory buffer.
  • A3DRepresentationItemExportToAcisBuffer(): Writes a representation item to a memory buffer.

Before exporting, ensure that the model contains the geometry and tessellation you expect. See our pages on tessellation for tips on generating visualization data for export.

B-rep

All B-rep data is exported with surfaces and curves approximated to the following types:

  • Surfaces: B-spline surface, Cone, Plane, Torus.
  • Curves: B-spline, Circle, Line, UV curve, Ellipse.

Tessellation

This format does not support tessellation representation.

Miscellaneous

Hidden Objects

ACIS does not support hidden objects. We export hidden objects as visible by default with A3DRepresentationItemExportToAcisBuffer(), but this is not possible with A3DAsmModelFileExportToAcisFile().

Unsupported Features

ACIS does not support PMI and views, so our ACIS writer does not export these elements. The ACIS kernel does not support conversion of tessellation to geometry, so exporting files with tessellation to ACIS will result in an empty model.