STEP is the current standard for exchange of CAD data between different software packages. BRL-CAD makes use of the STEPcode libraries to support its step-g converter, but the converter is still in its infancy.
The current importer focuses on AP203 import, and needs to support a large number of data types:
-
- Surfaces that are stored individually without Brep superstructure (see, for example, the wing shapes generated by OpenVSP: http://www.openvsp.org/wiki/doku.php?id=step) Even though these are not proper "solids" in the BRL-CAD sense of the term, we can and should import them - if nothing else, we can create one Brep object per surface and then develop post-processing tools to "stitch" the surfaces into a solid.
- Isolated curves can be brought in as part of sketch primitives.
- Polygonal data
- Unorganized triangle mesh data
- Metadata (in many cases can be mapped to attributes, worst case perhaps store as binary objects...)
- etc.
Right now our importer is AP203 only - we are also interested in AP203e2, AP214, and AP242.
References
- src/conv/step
- this is where the current step-g importers and exporters resides
- src/other/step
- this is STEPcode
- Recommended Practices for AP203
- Usage Guide for the STEP PDM Schema V1.2
Requirements
- Familiarity with C++