TopoManagers

How to compile

git clone --recurse-subprojects https://github.com/ezzieyguywuf/TopoManagers
cd TopoManagers
mkdir build
cd build
make -j8 all
make test # if you want to run the tests

What is it?

TopoManagers is a library which provides managers for topology. These managers handle various types of specialized solids. The interface for this management can be seen in the ISolidManager abstract base clase. In short, a solid manager will:

• manage an Occ::Solid (see https://github.com/ezzieyguywuf/OccWrapper)
• provide an updateSolid method, which allows the user the change the managed solid to a new Occ::Solid

Please note that the updateSolid method is not defined in tho ISolidManager abstract base class because its call signature can and will vary based on the specific use-case of the solid manager.

Why?

This project exists in order to deal with the pernicious "Topological Naming Issue" as defined by the FreeCAD community. More information can be seen https://forum.freecadweb.org/viewtopic.php?f=10&t=27278. In short, due to the way that topological entities are currently referenced in FreeCAD, there are situations in which a user will expect to have a constant reference to a particular entity when in fact this is not the case.

For an example of this, perform the following steps in FreeCAD:

• Create a new document
• Swich to the Part workbench
• Create a Box using the GUI button
• Create a Cylinder using the GUI button
• Fuse these two items together
• Fillet any edge on the Fused solid
• Finally, change the cylinder's height to 5 and 15

Notice that when you change the height of the cylinder, the filleted edge moves. The reason for this is discused in detail on the FreeCAD developper forums.

Project Status

The project is in its infancy. It is barely started. At this point, it is mostly a proof-of-concept to show how this general idea for managing topological entities can work.

TODO

• Add updateSolid to the ISolidManager abstract base class somehow
• Create a manager for 2d sketches, PlanarFaceSolidManager
• Create a manager for extruded 2d sketches, SweptSolidManager
• more....