What is this?

This is a game I designed with the purpose of being Turing complete! That means you can make any kind of computer or circuit in this game.

(By the formal definitions of computational complexity, you can make any Finite State Machine in Crabs, so technically it isn't Turing complete (YET), but this is what everyone calls it)

How do I use it?

I have some videos on crabs here (ordered from easiest to hardest)

Some simple designs: What are phase crabs?

More complex designs (including tunnel crabs): Finding bugs in my game (Crabs)

I'm making more videos on crabs all the time, and they'll all be in this playlist: Crab computers

Enjoy!

Controls

General

Left Click - draw

Right Click - delete

WASD - move

Scroll - zoom

Ctrl + scroll - change delay

Ctrl + shift + scroll - change frame skip

Space - play/pause

Enter - go forward one frame

Ctrl + S - save

H - toggle menu

Ctrl + H - toggle advanced overlay

Ctrl + G - toggle speed limit (vsync)

Camera

Shift + Z - rotate camera anticlockwise

Shift + X - rotate camera clockwise

Shift + C - lock camera to nearest 90°

Ctrl + R - reset camera rotation (this can reload the page, so please only use this shortcut outside of the web version)

Selection

Q - selection start

E - selection end

Z - rotate selection anticlockwise

X - rotate selection clockwise

Escape  - deselect

Ctrl + A - select all

Ctrl + C - copy selected from cursor

Ctrl + X - cut selected from cursor

Ctrl + V - paste selected at cursor

Ctrl + F - freeze selected crabs

Ctrl + Shift + F - unfreeze selected crabs

Alternate rulesets

Ctrl + 1 - regular mode

Ctrl + 2 - bounce edition

Crab/block Select

1 - horizontal crab

2 - vertical crab

3 - block (blue)

4 - rotator (purple)

5 - cloner (white)

6 - anti rotator (pink)

7 - destroyer (red)

8 - extender (green)

Please download the regular version!

The WebGL version of this game is a preview and will not be able to handle complicated builds, so if you like the game, please download the Windows or Mac version. If you have a different OS, please let me know and I will port it for you.

I hope you enjoy :)