Analysis Situs

Analysis Situs is an open-source prototyping workbench and an SDK to develop CAD/CAM/CAE algorithms.

Its main driving idea is to give CAD software developers a highly intuitive, visual, and customizable incubator where new CAD algorithms get born. The workbench utilizes C++ and Tcl as the main programming languages. The application comprises a hierarchically organized data model, VTK-based 3D viewers, and a scripting console. Provided is a bunch of geometry processing algorithms, ranging from CAD feature recognition to computations on meshes.

Technology-wise, Analysis Situs builds upon OpenCascade and another in-house open-source NURBS library. It accumulates a wide range of functionalities, covering classical B-rep modeling/inspection algorithms and some state-of-the-art approaches. The latter includes some algorithms developed in the frames of scientific research of its authors. The available tools are designed to be used as a basis for derived algorithms.

The initial intention behind this software was to bridge a gap between academic researchers and industrial consumers (to solve the "technology transfer" problem). The authors also use Analysis Situs to teach students and CAD practitioners low-level geometric modeling as well as to conduct their own research.

3-clause BSD
Industrial sector: 
Software Development, Machining
Software type: 
Open Source
Scope of application: 
3D modeling, CNC machining, Data Exchange
Functionality / feature-set: 
CAD feature recognition; Interactive inspection of CAD models and B-rep elements; Import and export in neutral CAD/mesh formats including STEP, STL, etc.; Voxelization of CAD models; Low-level NURBS computations; Validity checks for CAD models
Suitable for: 
Freelance, Enterprises, Research & Science, Personal, Startups
Deployment options: 
Desktop: Windows
Programming Languages: 
C++, Tcl
Support Options: 
Email, Forum/Community, Social Media, Video Tutorials/Webinar
Training Options: 
In Person, Live, Webinars, Documentation, Videos
Sergey Slyadnev

Q. Does the software allow for commercial use?
A. Yes. It comes with the fully permissive 3-clause BSD license.

Q. How many users does Analysis Situs have?
A. That's hard to estimate as we do not trace our users back. The software is also a bit specific as it is intended for CAD practitioners, researchers, engineers, and programmers. Some people use it once to solve their particular problem. Some others give Analysis Situs a slot in their daily business, e.g., to heal CAD geometry before numerical simulation. The most advanced use is to employ Analysis Situs as a framework to build up custom CAD applications. That happened several times with a range of industrial companies from CNC machining area and alike.

Q. What does the name mean?
A. “Analysis Situs” is the former name for “Topology” used back in the 19-th century. Since the main feature of the software is comprehensive analysis of a CAD part’s contents and features, we find that to be a good name. It is also a non-cliché one, although hard to pronounce.

Q. Can I freely integrate the pieces of Analysis Situs into my own software?
A. Yes, you are encouraged to do so.