Recs.
Updated
Godot is a free, open-source, and MIT licensed game development environment for 2D and 3D games, also well suited to building GUI applications.
SpecsUpdate
Pros
Pro Easily expanded scripting system
With 3.0's addition of NativeScript and PluginScript via GDNative, developers can easily define bindings for new scripting languages. In addition to the primarily supported C++, GDScript, VisualScript, and C# languages, the community has contributed D, Nim, and Python as well with more on the way.
Pro Easy to learn scripting language
Godot has their own scripting language called GDScript. The scripting language is easy to learn with Python-like syntax, but it is not Python. It's very powerful, easy to learn, and it's free of unnecessary things because it was custom built for optimized integration with the Godot Engine.
It can be used to add custom behaviors to any object by extending it with scripting, using the built-in editor with syntax highlighting and code completion.
A built-in debugger with breakpoints and stepping can be used and graphs for possible bottlenecks can be checked.
Pro Friendly towards Version Control Systems
The engine is build not only to support version control but to really use it. Scene files for example which usually get compiled into some sort of unreadable data stay in a text format - that way you can actually see your changes in a version control system like Git.
Pro Under constant development
This engine barely released one year ago has more than 1000 forks on github and about 100 developers. Not only that just a bit of browsing trough issues you will quickly find out the dev community loves new esp free technology and does not shy away from completely rewriting parts of the engine. The audio engine is being completely rewritten to use threads and so forth.
Cons
Con Primarily supports own proprietary language (GD Script)
While it's very accessible, and if you know Python you'll pick it up fast, having to learn a new language to fully make use of the platform can be a bit discouraging. And for those learning to code as well as learning Godot for the first time, many would rather learn a language they can 'take with them' when they explore other platforms in the future.
Recommendations
Comments
Flagged Pros + Cons
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b
Pro Outstanding toolkit for building GUI applications, not only games
Godot editor is made in Godot engine itself - "eat your own dog food" approach.
https://scribe.rip/swlh/what-makes-godot-engine-great-for-advance-gui-applications-b1cfb941df3b