ClassiCube is a custom Minecraft Classic and ClassiCube client written in C that works on Windows, OSX, Linux, BSD, Solaris, Haiku, and in a browser. It is not affiliated with (or supported by) Mojang AB, Minecraft, or Microsoft in any way.

You can grab the latest stable binaries from here and the very latest builds from here.

What ClassiCube is

• A complete re-implementation of Minecraft Classic, with optional additions.
• Lightweight, minimal memory usage compared to the vanilla client.
• Works with effectively all graphics cards that support OpenGL or Direct3D 9.

It does not work with 'modern/premium' Minecraft servers.

Requirements

• Windows: 2000 or later. (Windows 98 with KernelEx also technically works)
• macOS: macOS 10.5 or later. (Can be compiled to work with 10.3/10.4 though)
• Linux: libcurl and libopenal.

Note: When running from within VirtualBox, disable Mouse Integration, otherwise the camera will not work properly.

Instructions

Initially, you will need to run ClassiCube.exe to download the required assets from minecraft.net. Just click 'OK' to the dialog menu that appears when you start the launcher.

Singleplayer Run ClassiCube.exe, then click Singleplayer at the main menu.

Multiplayer Run ClassiCube.exe. You can connect to LAN/locally hosted servers, minecraft.net servers, and classicube.net servers through the launcher.

Windows specific

If you are stuck using the built-in OpenGL 1.1 software renderer, you can use the MESA software renderer from here for slightly better performance. Typically though, this occurs because you have not installed GPU drivers.

Compiling - Windows

Using Visual Studio

Open ClassiCube.sln and compile it.

If you get a The Windows SDK version 5.1 was not found compilation error, see here for how to fix

Using Visual Studio (command line)

1. Use 'Developer Tools for Visual Studio' from Start Menu
2. Navigate to directory with game's source code
3. Enter cl.exe *.c /link user32.lib gdi32.lib crypt32.lib ws2_32.lib wininet.lib winmm.lib dbghelp.lib d3d9.lib shell32.lib /out:ClassiCube.exe

Using MinGW-w64

I am assuming you used the installer from https://sourceforge.net/projects/mingw-w64/

1. Install MinGW-W64
2. Use either Run Terminal from Start Menu or run mingw-w64.bat in the installation folder
3. Navigate to directory with game's source code
4. Enter gcc *.c -o ClassiCube.exe -mwindows -lws2_32 -lwininet -lwinmm -limagehlp -lcrypt32 -ld3d9

Using MinGW

I am assuming you used the installer from http://www.mingw.org/

1. Install MinGW. You need mingw32-base-bin and msys-base-bin packages.
2. Run msys.bat in the C:\MinGW\msys\1.0 folder.
3. Navigate to directory with game's source code
4. Enter gcc *.c -o ClassiCube.exe -mwindows -lws2_32 -lwininet -lwinmm -limagehlp -lcrypt32 -ld3d9

Compiling - Linux

Using gcc/clang

Install appropriate libs as required. For ubuntu these are: libx11-dev, libxi-dev and libgl1-mesa-dev

gcc *.c -o ClassiCube -lm -lpthread -lX11 -lXi -lGL -ldl

Cross compiling for windows:

i686-w64-mingw32-gcc *.c -o ClassiCube.exe -mwindows -lws2_32 -lwininet -lwinmm -limagehlp -lcrypt32 -ld3d9

Raspberry pi

Although the regular linux compiliation flags will work fine, to take full advantage of the hardware:

gcc *.c -o ClassiCube -DCC_BUILD_RPI -lm -lpthread -lX11 -lEGL -lGLESv2 -ldl

Compiling - macOS

Using gcc/clang (32 bit)

cc *.c -o ClassiCube -framework Carbon -framework AGL -framework OpenGL

Using gcc/clang (64 bit)

cc *.c -o ClassiCube -framework Cocoa -framework OpenGL -lobjc

Compiling - other desktop OSes

FreeBSD

clang *.c -o ClassiCube -I /usr/local/include -L /usr/local/lib -lm -lpthread -lX11 -lXi -lGL -lexecinfo

OpenBSD

Install libexecinfo, curl and openal package if needed.

cc *.c -o ClassiCube -I /usr/X11R6/include -I /usr/local/include -L /usr/X11R6/lib -L /usr/local/lib -lm -lpthread -lX11 -lXi -lGL -lexecinfo

NetBSD

gcc *.c -o ClassiCube -I /usr/X11R7/include -I /usr/pkg/include -L /usr/X11R7/lib -L /usr/pkg/lib -lpthread -lX11 -lXi -lGL -lexecinfo

DragonflyBSD

gcc *.c -o ClassiCube -I /usr/local/include -L /usr/local/lib -lm -lpthread -lX11 -lXi -lGL -lexecinfo

Solaris

gcc *.c -o ClassiCube -lm -lsocket -lX11 -lXi -lGL

NOTE: You have to change entry->d_type == DT_DIR to Directory_Exists(&path) (TODO do this automatically)

Haiku

Install libsdl2_devel, openal_devel, and libexecinfo_devel package if needed.

gcc *.c -o ClassiCube -lm -lexecinfo -lGL -lnetwork -lSDL2

NOTE: You have to change entry->d_type == DT_DIR to Directory_Exists(&path) (TODO do this automatically)

Compiling - other

Web

emcc *.c -s FETCH=1 -s ALLOW_MEMORY_GROWTH=1 --preload-file texpacks/default.zip

The generated javascript file has some issues. See here for how to fix

Other

You'll have to write the necessary code. You should read portability.md in doc folder.

Known compilation errors

Fixes for compilation errors when using musl or old glibc for C standard library

Documentation

Functions and variables in .h files are mostly documented.

Further information (e.g. style) for the game's source code can be found in the doc and misc folders.

Tips

• Press escape (after joining a world) or pause to switch to the pause menu.

• Pause menu -> Options -> Controls lists all of the key combinations used by the client.

• Note that toggling 'vsync' to on will minimise CPU usage, while off will maximimise chunk loading speed.

• Press F to cycle view distance. A smaller number of visible chunks can improve performance.

• If the server has disabled hacks, key combinations such as fly and speed will not do anything.

• To see the list of built in commands, type /client.

• To see help for a given built in command, type /client help <command name>.

Open source technologies

• curl - HTTP/HTTPS for linux and macOS
• FreeType - Font handling for all platforms
• GCC - Compiles client for linux
• MinGW-w64 - Compiles client for windows
• Clang - Compiles client for macOS
• Emscripten - Compiles client for web