Thank you for the project! I used it to generate some maps to play locally back in 2017.
I parallelized (CPU) the height map generation (approx. 10x speed up on my machine with 16 threads). Going to throw in lwjgl and try to get opencl working as a learning exercise next. I also aimed for a 1-click build step: If you're on Windows and have the JDK installed, you can simply download the repo and double click gradlew.bat to have the project build and run. https://github.com/rmbreak/WGenerator