Add build instructions to readme.md

This includes package lists for various distributions.

readme.md

@@ -21,8 +21,59 @@ text including copyright information.
 Please visit https://www.teeworlds.com/ for up-to-date information about
 the game, including new versions, custom maps and much more.
 
-Instructions to build the game can be found at 
-https://teeworlds.com/?page=docs&wiki=compiling_everything. In
-particular, you will need SDL2 and FreeType installed.
-
 Originally written by Magnus Auvinen.
+
+
+Building on Linux
+=================
+
+Installing dependencies
+-----------------------
+
+    # Debian/Ubuntu
+    sudo apt install build-essential cmake git libfreetype6-dev libsdl2-dev libpnglite-dev libwavpack-dev python3
+
+    # Fedora
+    sudo dnf install @development-tools cmake gcc-c++ git freetype-devel mesa-libGLU-devel pnglite-devel python3 SDL2-devel wavpack-devel
+
+    # Arch Linux (doesn't have pnglite in its repositories)
+    sudo pacman -S --needed base-devel cmake freetype2 git glu python sdl2 wavpack
+
+
+Downloading repository
+----------------------
+
+    git clone https://github.com/teeworlds/teeworlds --recurse-submodules
+    cd teeworlds
+
+    # If you already cloned the repository before, use:
+    # git submodule update --init
+
+
+Building
+--------
+
+    mkdir -p build
+    cd build
+    cmake ..
+    make
+
+On subsequent builds, you only have to repeat the `make` step.
+
+
+Build options
+-------------
+
+The following options can be passed to the `cmake ..` command line (between the
+`cmake` and `..`) in the "Building" step above.
+
+`-GNinja`: Use the Ninja build system instead of Make. This automatically
+parallizes the build and is generally **faster**. (Needs `sudo apt install
+ninja-build` on Debian, `sudo dnf install ninja-build` on Fedora, and `sudo
+pacman -S --needed ninja` on Arch Linux.)
+
+`-DDEV=ON`: Enable debug mode and disable some release mechanics. This leads to
+**faster** builds.
+
+`-DCLIENT=OFF`: Disable generation of the client target. Can be useful on
+headless servers which don't have graphics libraries like SDL2 installed.