About LGS 3D                  About LGS 2D

The LGS 3D geometric constraint solver, developed and supported by LEDAS since 2005, is offered for licensing to all CAD/CAM/CAE software development companies at an affordable price. It is commonly used as parametric engine for history-free 3D geometry editing, assembly design, motion analysis, and other geometric modeling applications. LGS 3D is a cross-platform software packages running on 32- and 64-bit versions of Windows, Linux, Mac OS X, *BSD, AIX, HP-UX, Sun Solaris, and other OSes. Coded in C++, LGS 3D has a C-style API for easy integration into a broad range of software applications using a variety of wrappers, such as .NET, Java, and C++.

LGS 3D supports the creation and modification of geometric models by means of explicit or implicit constraints. (Geometric objects include points, lines, circles, planes, cylinders, spheres, parametric curves, surfaces and swept surfaces.) Objects can be fixed in the absolute coordinate system or relative to each other. Supported geometric constraints include logical constraints between geometric entities (coincidence, parallelism, tangency, and so on), and dimensional constraints that specify the required values for distances, angles, or radiuses. LGS 3D moves and rotates objects to positions that satisfy all constraints, yet minimizes transformations from the initial configuration. Other LGS functions implement advanced features of CAD/CAM/CAE systems, such as diagnostics of over- and under-defined parts of models, engineering variables and equations, help points, and tolerance management.

Sample application named Lege’n’d 3D is available for free download from the LEDAS Web site. It is bundled with a set of representative examples of different kinds of 3D assemblies. The application can be used by anyone to test the functionality, robustness, and performance of LGS 3D. Lege’n’d 3D was created with the Open CASCADE open-source application framework, and its source code is available to all licensees of LGS 3D.

Current version is LGS 3D 3.0 (released in April 2010)

Version 3.0’s primary new feature is its ability to adjust the radii of circles, cylinders, and spheres automatically to satisfy constraints. This function allows users to modify fillets, blends, and round holes in their models parametrically. By default, the radii are fixed so that existing assembly design and kinematic simulation applications implemented with previous versions of LGS 3D continue to work as expected.

Version 3.0 also contains significant improvements for the support of periodic curves and surfaces, improvements that were based on testing by customers and their dynamic scenarios. The algorithms that handle over-defined constraint diagnostics and move-under constraints have been tuned using feedback from customers. The behavior of LGS 3D in solving planar angles is now more natural.

Additional improvements to LGS 3D 3.0 include extended API error diagnostics, corrected journaling mechanisms, and bug fixes.

Version 3.0 of LGS 3D is already embedded in several commercial applications, including a recent release of the RhinoDirect plug-in for McNeel & Associates’ Rhinoceros 3D modeling software. RhinoDirect, as a part of the Driving Dimensions product line, aims at making advanced mechanical CAD technology available to all users of popular 3D software at an affordable price. For more information, please visit www.DrivingDimensions.com.

For the full list of changes see Release Status page.