And when its be changed to cmake?
- Сurrent build system is not compatible with anything.
- Difficult to include third party libraries
- And more other things
What r u talking about?
I’m also a little unclear on what you’re asking, but I suspect by “not compatible with anything” you’re referring to C++ tools (like doxygen, or code analysis tools that work on source code), or wanting to integrate with a different build system (like CMake), or use third-party libraries that expect to use CMake (or whatever) as their build system.
And… I mean, you’re not wrong?
Unreal C++ is… really more of another language built on top of C++ in many ways, given the sheer complexity of what UnrealBuildTool does. It’s not altogether unlike the venerable cross-platform “Q Toolkit”, a.k.a. Qt. (I wouldn’t honestly be surprised if Qt’s extensions to C++ – Q_PROPERTY(), Q_SLOTS, Q_SIGNALS, and so on – were an inspiration for a lot of how Unreal handles C++.)
And much like Qt, a lot of that saves us a great deal of time writing what would otherwise be boilerplate code; being able to do Q_PROPERTY() – or UPROPERTY() in Unreal – in one line instead of defining a bunch of metadata about properties and access permissions and whatnot in a class constructor is unquestionably faster. (And arguably, more maintainable… at least if you’re familiar with that syntax.)
But like Qt and qmake (or the Not Small amount of CMake mkspecs that provide qmake-like functionality to build Qt stuff under CMake), the trade-off is in having to use special tools that create Qt’s “MOC” intermediate step, or Unreal’s “.generated.cpp/.h” files. And in the fact that as a result of that extended syntax, you lose the option to use fairly common tools like doxygen, at least without some additional steps.
Some of that can be dealt with, of course. I have a Python script that I can use as a doxygen filter, for instance, to allow me to still generate doxygen documentation from my Unreal C++ source code; it strips out all the UBT macros and syntax, allowing doxygen to actually recognize what bits of code the doxygen-style comments actually refer to.
And there are a number of tools that have arisen in ecosystems like these two; there’s plenty of tools that integrate with Qt’s way of doing things. JetBrains has CLion, a C++ IDE that tightly integrates with Qt (and, for that matter, has support for Unreal-specific stuff). They also make Rider, an IDE that really tightly integrates with Unreal, so much so that it feels like part of the product.
But otherwise… yeah, you’re right. You don’t so much take this system and integrate it into some other build ecosystem. You need to approach it from the viewpoint that you’re taking other things and integrating them into the Unreal (or Qt) build architecture.
And unfortunately, that’s the tradeoff we make for not needing to write several thousand lines of repetitive code in every single project to (for instance) create all the metadata and links necessary to expose properties and functions to the in-engine Blueprint scripting system.
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I tell about what i can’t use packet managers(like vcpkg, conan), build tools like cmake with UE.
I have no easy way to develop and debug my own shared(shared between UE and my own application/service) library with UE.
I can use cmake and packet managers with many things(Qt is included).
UE is execption.
P.S.: Sory for my English. It is not pimary language for me.