Well done. You did make the right decission. And it should not even be hard.
You are going to need cmake, make and gcc in order to be able to compile C++ sources on your system at all. It is impossible to predict how the packages are called by your package manager but in my experience they are called exactly that. So in Ubuntu and Debian for example you would just enter: apt-get install cmake make gcc
Remember, you have to be root, so you might want to prefix sudo, or do sudo su first or just su if you are on debian.
So at the moment of this writing you can see the libraries the project is linking to in CMakeList.txt. They are GLEW GL GLU glut assimp.
Now how will you satisfy these dependencies? No problem. You might notice that when you are looking for them in your package manager that you get overwhelmed by a list of possible installation candidates, how do you know which one is the right one?
An easy rule that applies to many libraries is that a library has the lib prefix and then, since you want to install the files for development there is a dev in the name. Pretty much like libfoo-dev for most libraries.
So for example to satisfy the dependencies in debian type the following to install all dependencies: apt-get install libglew-dev libgl1-mesa-dev libglew-dev freeglut3-dev libassimp-dev
See how libgl1-mesa-dev does not play by the rules? There are reasons for that, which we do not care about. Something similar happens to glut, too. We are using the freeglut implemenation instead of glut.
You also need an additional library which may or may not go by the name libfreeimage-dev.
Get the source code by downloading a release https://github.com/GlPortal/glPortal/releases or after installing git with either of the following commands stable: git clone https://github.com/hhirsch/glPortal.git development: git clone https://github.com/GlPortal/glPortal.git Make sure to check the README.org and COMPILE.org from the release you downloaded in case there are differences in the compile workflow for it.
Then in the root directory of the downloaded source type cmake ./
Now if this throws an error you have to fix something first. If you don’t manage to fix the error, use the bugtracker https://github.com/hhirsch/glPortal/issues to report what you did, and what error you got.
If the command did not produce an error, you can build the binary by typing in: make in the root directory of the downloaded source.
If this produces no error you have built the binary and should be able to start GlPortal by typing in: make run
If you get errors try running cmake source again.
This does not work for you? Help us figure out what we missed to make this work on your system.