I thought this was going to be a small release with one main feature, but it turns out it is actually pretty huge.

The big main new feature is Clone. Clone is what you need when you want to duplicate components, but symmetry isn’t doing it for you. So all of you DEP enthusiasts, this one is for you.

Clone is a new Geom type that gets its shape and behavior from another Original Geom. By default, the Clone also gets its basic Parms and other settings from the Original – Set membership, color, mass properties, attachment, symmetry, etc. If you want to set those things separately, there is an option for that. By default, a clone has its own transformation (XForm) Parms, so you can move it around the model.

You can clone a group of components at once with the Clone button on the Geom Browser. In a hierarchy, it will make the top-level Clone’s XForm independent, but all the children will get their XForm from their original. That way, if you have a group of components that are attached together with certain offsets, those offsets will be cloned while the top level entity can be used to reposition the whole clone hierarchy.

The tricky part of Clone was not the shape, it was the behavior. A Clone of a wing needs to act like a wing, a propeller needs to act like a prop, landing gear like landing gear. Any place OpenVSP ‘knows’ what kind of Geometry it is, a Clone must pretend to be that kind. There is a lot of this.

A Clone can be replaced with a copy of the original, so if you decide their shape needs to diverge, it is a quick operation. OpenVSP will do everything it can to preserve the ID’s through this operation, so if your Clone used Parmameter linking, it should mostly work after being replaced.

A lot was done to make Clone very efficient, so it should be really fast. The Update speed is trivial compared to the user time it previously took to maintain two identical components (or to link everything in them), but now both should be great.

Clones can be flipped/mirrored copies, so all Geom’s gained that capability so a flipped clone replaced with a native Geom would still work out right. If you’re into making asymmetrical aircraft, then flipping a wing will be a nice change.

OpenVSP’s meshing stuff got a lot of attention. This improves CFDMesh, FEAMesh, and the trimmed CAD export (though I’ll speak about it in terms of CFDMesh). CFDMesh is faster on a single thread. CFDMesh is now also multi-threaded. CFDMesh is more robust. CFDMesh will produce higher quality output. If you use any of the meshing stuff in OpenVSP, you’ll like the changes.

CFDMesh can now write out POGS (Pre-processor for Overset Grid Sumulations) files. POGS is an automation tool for NASA’s Chimera Grid Tools (CGT) being developed by William Chan at NASA Ames. POGS output is accessed through CFDMesh. I expect this capability to continue to evolve.

POGS prefers fewer surface patches where possible (but not too few). So there is now an option that will merge together the top/bottom patches of wing trailing edges and tip caps and the top/bottom patches of bodies. This option will not work properly with the extended tip cap types, but should otherwise work pretty well.

STEP and IGES export got a lot of attention. This entails both fixes as well as improvements. Intersection curves are now piecewise cubic and should be more accurate with fewer segments. If you use an OpenVSP to CAD (or preprocessor) workflow, give it another try, I’m optimistic that things will be a lot better.

There is a new STEP/IGES export mode — split and stitch. In this mode, surface patches are split apart, degenerate patches are discarded, and then the patches are stitched back together into watertight BREPs. Those BREPs are not intersected or trimmed. This should be an interesting option for tools that didn’t like our monolithic quilts with embedded degenerate patches, or the hassle with dealign with a large number of split patches, and where our trimmed BREP didn’t work for you (do try it again though). Every CAD export path is now tested by reading the file back with OpenCASCADE.

Hinges can now be passed to CBAERO as all-moving control surfaces through CFDMesh.

The Design Variable capability now lets the user specify min/max bounds for the DVs. OpenVSP doesn’t do anything with them, but external tools that use the *.des file now have an easy for the user to put limits on the vars.

Structures and Trimmed Surfaces now write only meshes and STEP/IGES. The *.srf, *.curv, and *.p3d outputs and their options are gone. From the API, FeaMeshAnalysis only meshes; use the new FeaMeshExport analysis to write the files.

Features:

• Clone Geom
• Flip for every Geom
• Split and stitched STEP and IGES export (File -> Export)
• POGS output from CFDMesh
• CFDMesh faster single threaded
• CFDMesh multi-threaded
• CFDMesh more robust
• CFDMesh higher quality
• STEP/IGES Export greatly improved
• Hinges as all-moving control surfaces for CBAERO via CFDMesh
• Design variables have user determined bounds

Build System:

• Move Mac Aarch64 build to MacOS-15
• Code-Eli updates
• Triangle updates
• libIGES update

Bug Fixes:

• Many STEP and IGES export fixes (units, surface orientation, trim curves, tolerances)
• VSPAERO viscous forces used a point just behind the leading edge, tilting them toward one surface
• VSPAERO control groups and adjoint side force derivatives
• VSPAERO launch race condition
• GUI layout cleanup — widgets that spilled outside their groups
• Many other bugs