Hello, as the author of the "GD Script" book I am starting to make an e-book about advanced use of GD Script. The reader will find a lot of GD Script codes and concepts inside. In the beginning, you will start with coding concepts from the previous book (like button creation) and then you will go to more complex parts of code.The new e-book project will cover the advanced use of Godot GD Script. Godot is a leading game engine, and the latest stable version is 3.1.