magic_get VS OpenSceneGraph

Maybe this: https://github.com/apolukhin/magic_get

You can access non-static member variables with structured bindings. See for instance magic_get/boostPfr https://github.com/apolukhin/magic_get. Structured bindings will only bind to the accessible members (not private). Magic get works by by finding the number of member variables, converting the struct to a tuple (with a function that is specialized for the number of fields), and finally accessing the members through the tuple (supporting indexing and iteration). It does not grant access to the member names, but it is sufficient for some reflection.

Libraries like magic_get expose the members of an aggregate class/struct to allow writing generic code for things like pretty printing and serialization without anything special done to the class itself. They often rely on structured bindings for the decomposition (*), but find the number of elements via SFINAE on aggregate initialization, as an aggregate type can be initialized only from as many objects as it has members. It would be nicer if you could SFINAE directly on the structured binding itself, as then the type could have user-defined constructors (which aggregates can't). Unfortunately, this is not possible since structured binding is a statement and not an expression. Unless you're using Clang, where the GNU statement expressions extension allows you to do SFINAE on them, as in here.

No RTTI required, but the types are required to be aggregates (no constructors defined). It's possible to count the number of members using SFINAE by trying different numbers of inputs to the aggregate constructor using a type that's castable to anything, and then enumerate the members with a similar trick (or use structured binding to pull them out directly). I think he uses magic_get which is the most popular library for this trick.

take a look at magic_get to get access to all struct members. No idea what your plan is with foo and the preprocessor though.

Neat! Have you considered using magic_get?

It is possible with some hacks https://github.com/apolukhin/magic_get

I actually reference it near the bottom of the article under its original name, magic_get! I was disappointed to discover that this library did it a similar way first before me while researching 😅

I started in 2001 with OpenSceneGraph which made extensive use of intrusive pointers. This was 10 years before C++11 note. That codebase continues to be relevant and as performing as ever.

browse github and try to contribute. I started with OpenSceneGraph

I have been using OpenSceneGraph for over 20 years. It is used in the military a lot and I myself have seen it used to simulate war scenarios with realtime data aboard of a command-and-control center of a battleship.

Does http://www.openscenegraph.org/ fit?

Speed Dreams: It is a fork of TORCS, and was born as the need to include many more functions to the latter. In Speed Dreams the menus would be completely redesigned, adding many more options and making them much more intuitive; the game acquired dynamic time, improvements in reflections, career mode, a new simulation mode and multi threading. Over time many more options were implemented, such as local multiplayer mode, Force Feedback, and of course more and better cars and tracks, a new and more powerfull graphic engine (OpenSceneGraph) among other things, making it a much more complete game than its predecessor. They recently they have presented version 2.2.3. You can also install it in AppImage and Flatpak format.

Here is an example: https://github.com/openscenegraph/OpenSceneGraph/blob/master/examples/osgsimplegl3/osgsimplegl3.cpp

openscenegraph (mainly focuses on graphics, used by openmw for example)

Is not little, is very complex open source racing simulator. There are a lot of cars, categories, tracks. The physics has a lot of work . About the graphics, the devs are working on change the graphic engine to OpenSceneGraph, that actually works, but needs much more polishing. You can see his quality on this video: https://youtu.be/4daTgcxEWRg

I love Godot for a complete game engine. For just the renderer you could consider http://www.openscenegraph.org