Scalable Interfaces for Geometry and Mesh based Applications

What is Lasso ?

Posted by on Jun 11, 2014 in Lasso

The Lasso Relations Tool

Each ITAPS interface encapsulates functionality that “belongs” together, for example mesh or geometric model functionality. In some cases, however, data in several of these interfaces need to be related together. For example, a collection of mesh faces should be related to the geometric model face which they discretize. The ITAPS Relations interface iRel accomplishes this in a way which allows the lower-level interfaces to remain independent.

iRel defines relations as pairwise associations between entities or entity sets. Related entities can be in the same or different interfaces. A given relation is created for a given pair of interfaces and returned in the form of a Relation Handle. After a specific relation pair has been created, concrete relations for that pair can be assigned and retrieved for specific entities using set and get functions on the iRel interface. A given interface instance can appear in one or many relation pairs, each identified by the relation handle.

The Lasso tool implements the iRel interface, working through the other ITAPS interfaces. Lasso can recover the associations between mesh and geometric model entities those mesh elements discretize. Lasso currently works with geometry and mesh read into the CGM and MOAB components from “.cub” save/restore files written by the CUBIT mesh generation toolkit.

Lasso is maintained in a world-readable Git repository. If you would like to participate in the development of Lasso, contact Vijay Mahadevan for getting write access to the Lasso repository.


Lasso version 3.0.0: Lasso version 3.0.0 was released in March 2012; see the download link below.


If you use Lasso, please be kind enough to send us a note about how you’re using it, to vijaysm _at_ Feel free to send any bug reports and suggested improvements there too!


See release policies used for Lasso.
[Lasso3.0.0]:: Released March 23, 2012.

Building sources

[Building Lasso]:: How to build Lasso from scratch, with dependencies, on other platforms, etc.
[PyTAPS]: A Python implementation of iRel can be used with Lasso. Instructions on installing PyTAPS and configuring Lasso (and other libraries) for use with PyTAPS are found here.

** Nightly shared builds of CGM, MOAB, Lasso and PyTAPS are available on MCS machines at Argonne and checked daily with different configuration setups.

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