All the libraries linked against are included in the include folder as git submodules that point to the official repos. You need to clone their source code:

git submodule update --init

Create the output build folder:

mkdir build

Create more output folders (I need to automate this in the Makefile somehow:):

mkdir obj
mkdir obj/anims
mkdir obj/models
mkdir obj/png

Generate the 3D assets:

python3 process_assets.py

sudo apt-get install libsdl2-dev libsdl2-gfx-dev libsdl2-image-dev
sudo apt-get install libglew-dev

https://github.com/libsdl-org/SDL/blob/main/docs/README-linux.md

Run make build/linux and open the output in ./build.

Alternatively: ./linux_run.sh

apt install mingw-w64

Run make -s windows and open the output in ./build.

Alternatively: ./windows_run.sh