Compilation on Windows
I will work on transferring Computree knowledge to this page to make compilation easier for you.
The first thing to do is to get access to Computree. Computree is free, but you need to get an account. As soon as you have the account you have full access to the development platform of Computree. You will find a wiki entry with compile instructions. Please not that you will need to set up the optional dependencies PCL as well as GLS. You should always stick to the referenced versions of the dependencies. Other versions might work, but I often enough run into troubles by just installing the latest library version I found.
As soon as you have compiled Computree you can start compiling SimpleForest. Make sure you can start Computree before doing so. You will find source code on GitLab. Simply clone the source code into your Computree code folder. You should now have a folder named pluginSimpleForest in your computree folder. The pluginSimpleForest folder contains a subfolder named pluginsimpleforest. Do not get confused here, everything is fine. You only need to add into the all.pro file an entry now that QMake is aware of pluginSimpleForest. Add to the SUBDIRS where also other plugin are referenced to the line pluginSimpleForest/pluginsimpleforest/pluginsimpleforest.pro \. When you now save the all.pro file in QT Creator QMake runs again and the pluginsimpleforest should show up in the project explorer. Right click pluginsimpleforest and choose Build pluginsimpleforest. This is all you need to do.