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What tools are availible for pre-processing Cart3D triangulations?
Postprocessing Options?
What about CGNS?
Clic: Lift, Drag and Moment - Postprocessing of Aerodynamic data
  Wish List-

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File Import Tools:
Cart3D comes with several tools for for importing data. Most of these are documented on the Surface Modeling pages. These tools allow you to import geometry from STL, DXF, OFF, FNF triangulations, or from structured surface meshes in LaWGS or Plot3D format. Using these tools you can easilly convert your input geometry into Cart3D as a single component, configuration, or a final wetted surface. 

Overgrid:
But what about actually viewing and manipulating these components? Fortunately, several users and collaborators have developed tools to allow you to do this. Of those that have found their way back to us, William Chan's Overgrid package is by far the best and the most acessible. Overgrid is actually part of NASA's Chimera Grid Tools (CGT) package, but thanks to a happy collaboration between ourselves and the CGT team, the software can read, manipulate and write Cart3D single component, configuration, or  wetted surface triangulations. For viewing triangulations, and moving components, its extremely useful. Here are a couple of screen shots showing overgrid's 
triangulation editor:
 

click to enlarge either image

One final note. Although within Cart3D, we dont enforce file naming conventions, Overgrid does expect triangulations to conform to the naming conventions listed here. You'll be asked to sign an NDA when you request Overgrid.

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Volume/Surface Visualization:
We have developed several in-house packages for viewing Cart3D solutions and remapping the discrete solutions back to the input triangulations.  However none of these packages are ready for distribution, and we don't intend to start supporting them, since there are well-supported comercial options availible. The most inexpensive option is to use Amtec'sTecplot program (see Note 2). For a bit more $$ you can invest in Intellignet Light's  Fieldview, (seeNote 4) which is  currently supported by the tiger2fv converter. Here is a table summarizing the postprocessing options supported by Tiger, flowCart and some of the auxiliary programs:
 

program	dataset type	commercial post-processor supported
intersect	surface triangulation	Tecplot
mgPrep	cutting planes	Tecplot
Tiger	surface trangulations + flow variables	Tecplot, Fieldview
tiger2tec	3D volume mesh + flow variables	Tecplot
tiger2fv	3D volume mesh + flow variables	Fieldview
flowCart	surface triangulations + cutting Planes + flow variables	Tecplot

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Good question. There is currently no CGNS standard for Cartesian grids, but it is something that we'd very much like to support and we're working with the CGNS team to develop this standard. When this is done, we'll add CGNS support into Cart3D. Of course The CGNS system already does support unstructured surface triangulations and we do have translators for Cart3D surface triangulations (all types) and CGNS. These were written by the CGNS team and you should drop a note to CGNS-Support@CGNS.org to get a copy of these translators. 

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Clic is a Component based force and moment module developed as a post-processor and data-extractor for Cart3D. Its an extremely flexible and powerful package. Using clic, you can extract Cp cuts on any component or group of components in your configuration, you can compute LDM (lift, drag, moment) for components, component groups or configurations, and extract the usual bevy of point-moments, line-moments ("hinge moments") etc.. If you want to see some of what it was designed to do, take a look at the original ISO software project plan (here, 64kb acrobat format). Clic can be run as a postprocessor, or called directly through an API. The clic home page will get you started with the package. 

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One thing that would be very useful, is to have a converter between *.tri and *.triq to *.vrml files. 
Such a utility would permit 3D visualization from within a browser. If you're a Cart3D users, think about writing and submitting such a utility back to us. It would help the whole userbase. In vrml, you can assign colors based on a scalar, so it would be easy to shade the models using scalars/flow variables in the *.triq files. This kind of platform independent visualization would free us from needing to rely on 3rd party visualization. We could write this ourselves, but it would take time away from other development. 

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last update 1 Aug, 2000, M. Aftosmis