Automating DXF import to QUEST

QUEST doesn't come with a BCL command for easily importing geometry, and although that would be very convenient, it's still possible to convert various CAD geometry to QUEST's PDB format.

QUEST doesn't have CAD converts baked into the QUEST.exe application file, but rather uses standalone executables located in the quest\bin folder in your QUEST installation. QUEST simply calls these executables using command line arguments to pass in information about what the user is trying to do through the QUEST UI. The converter then performs the conversion, and dumps out a temporary pdb file into your temp directory (default is C:\Tmp). QUEST has been waiting for the converter exe file to terminate, after which it just does a "retrieve" of the temp file the converter created.

So, in a nutshell, to automate this ourselves, we simply have to call the appropriate converter with the right command line arguments, and we can go around the relatively clunky QUEST UI for dealing with our CAD importing.

My use case will be generating dxf/dwg layouts from vector drawings in MS Visio, and generating a pdb file for QUEST. This means I'll be using VBA in Visio, but the same thing could easily be done using SCL (although there might be a few snags, such as making your SCL code wait until the conversion is complete)

Before I start into laying out the arguments for converting a dwg to pdb, I should mention that DELMIA/Deneb have made it a little easier on us in running these converters. They have provided some DOS batch files for setting environment variables, which the converters basically need to be sure you are a licensed QUEST user.

So to convert dwg to pdb, we use the dwg2pdb.bat and corresponding dwg2pdb.exe files. If you look at dwg2pdb.bat, you can see there's about 5 lines for telling Windows where dwg2pdb.exe is. You can get away with deleting all that junk, and finding the line that says:

%DENEB_BIN_DIR%\dwg2pdb.exe $1 ...

and replacing the %DENEB_BIN_DIR% with the full path to your QUEST installations bin dir (mine is C:\delmia\quest\bin)

The only environment variable you need to make sure is set is the LM_LICENSE_FILE, which you should have set already in your quest.bat file, and if your installation of QUEST works, you shouldn't even need to change this.

So, on to the command line arguments. To see what the arguments are, I quickly built an exe in VB6 that just echos out the command line arguments in a message box. So I renamed my dwg2pdb.exe to something else, and renamed my command line echo exe to dwg2pdb.exe. Then I went into QUEST and ran an import, at which time I was shown that there are four arguments you need to pass to run a dwg conversion:

1. The full path to the dwg/dxf input file
2. The full path to the output pdb file location
3. The full path to a configuration file called dwg_cmd (more on that later)
4. The full path to an output text callout file location

The first two arguments are fairly straightforward. You just need to get the full path to the input file, and decide where to send the output file.

The third argument is for the full path to a file called "dwg_cmd", which is automatically generated by the QUEST UI when you tell QUEST some of the parameters of the input geometry, such as the default length units, point tolerance, etc... On my system, at least, this file was stored in the quest directory. So I modified it to a default length unit of Inches, and copied the file to quest\bin. This will serve as my default dwg import profile.

The fourth and final argument was the full path to where you'd like the converter to build a plain text file containing all the text from the dwg/dxf file. You'll notice when imporing a file with text, you get the floating annotations containing your drawing text. I guess this is where that text comes from. The format is somewhat easy to understand. Basically, the first line details the number of text annotations there are. Then the annotations start. The first three lines of an annotation are the x, y, and z locations of the text callout, respectively. I'm not entirely certain what the next four lines are, though they could be rotation angles and font sizes. The next line is the number of characters in the callout, and the final line of a callout is the callout text.

Okay, so now we know all the arguments we'll need to pass to dwg2pdb.exe or .bat, to get things translated. When I tried this though, I got an error saying the executable could not find lmgr8b.dll, which is some runtime that QUEST needs in order to operate (and I'm assuming it's for the FlexLM license manager QUEST uses)

To fix this problem, I simply copied the lmgr8b.dll file from my quest dir into my quest\bin dir, and everything seemed to work. I could pass in my arguments and get a pdb file out.

So now anywhere I can generate command line arguments, I can also convert dwg/dxf files into the QUEST format automatically.