What are DXF and DWG files? When will I encounter them during the eDiscovery process?
DXF and DWG are file formats created for the software AutoCAD - a design and drafting tool commonly used by designers, engineers, architects, city planners, etc. They allow users to build complex 3D and 2D plans and models, and are now widely adopted in other computer-aided design (CAD) & engineering programs.
DWG is the native file format for AutoCAD (meaning that by default files in AutoCAD are saved as DWG files), whereas the DXF format was designed to be used by other programs that are not capable of reading (the more complex) DWG files. Because of how widespread the formats have become, you will likely need to deal with them at some point. Widespread usage? That must mean that they are easy to deal with, right? You’d be surprised! There’s a significant lack of support for these file types amongst eDiscovery services.
What challenges do they create for eDiscovery?
Limitations around “views” and “layouts”
DXF and DWG files can represent models that are both 2D and 3D. Regardless of whether the models are 2D or 3D, it’s possible for them to have user-defined “views” and “layouts” that indicate areas of interest. The problem, however, is that the names of the views and layouts that need to be rendered must be explicitly specified. And it’s not easy to get this information from the files. So when most eDiscovery services say they can support the DXF and DWG file formats, it’s likely that they can only produce a single render of the model itself, not renders of the views or layouts (i.e., the parts of the models that you want to focus on.)
Another complication these filetypes bring is that there are dozens of variations and versions of the formats, going back to the early 1980s. The PRONOM file type database lists 26 variations of the DXF format and 19 variations of DWG, and there are even more that it does not account for. Fully supporting DXF and DWG files well requires knowing about and working with all of these variations. As DXF is the simpler and better-documented format intended for widespread use, there are freely-available and open-source tools with which they can be accessed. But a constant limitation is that the tools only support ASCII versions, and not binary ones (about half of the overall DXF variations.) This means that it is that much harder for an eDiscovery provider to offer support for all of the files you need to view.
What can GoldFynch do?
This is why you’re here, right? GoldFynch can:
- Handle DWG in binary, and DXF in both the ASCII and binary formats (where most other systems can only work with ASCII)
- Extract layer names (and other strings)
- Render all existing 2D “views” (i.e., user-defined regions of interest,) angles, and layouts of the 3D model - not just the ones that the user is able to explicitly specify
- Pull out metadata like the date created, date last modified, etc.. And also render a table of basic metadata and any layers
- Render all defined paper layouts
- Render the model layout and any defined paper layouts using the saved paper sizes (for example, large architectural sheets will have a large PDF rendering)
- Render the full “extent” of the layout of a paper layout if it extends beyond the paper itself
- “Thaw” (make visible) all layers before rendering
- Set colors to ensure all lines are visible (as opposed to where they are not visible on a similarly-colored background)