Binary Tetris - 140byt.es

A simplified variant of the classic tetris game done in less than 140 bytes of JavaScript.

Click here to play the DEMO!

NEW: A standalone version in 300 bytes: aem1k.com/tetris

Source

    function(a,b,c,d){d+=c;
    return[d<0|a&b<<d?a=
    parseInt((a|b<<c)
    .toString(d=32,b=new Date&2|1)
    .replace('v',''),d):
    a|b<<d,a,b,d]}

Feel free to edit the source and follow me on Twitter (@aemkei).

Example Layout

1.       2.       3.       4.       5.

.....    .....    .....    .....    .....
.....    .....    .....    .....    .....
...##    .....    .....    .....    .....
.....    ...##    .....    .....    .....
##...    ##...    ##.##    ##...    .....
###..    ###..    ###..    #####    ##...

More Information

The main logic to move blocks, detect collision, assign new blocks, remove full lines and render the layout are included. Excluded are keyboard controls and the final rendering.

This version is heavy based on binary numbers and bit shift operators. I had to limit the board size to 5x6 (30 bits), because JavaScript converts numbers to 32-bit integers when using bitwise operators. The two left bits are later uses to add the correct padding when dealing with numbers that start with “0”.

Basic Concept

The Board

                  00000         .....
798               11000   =>    ##... 
                  11110         ####.

The Block

3                 00011  =>     ...##

Checking for Collision

                  00000         .....
798&3 = 2         00000  =>     .....
                  00010         ...X.

Moving the Block at X Axis

3 << 1 = 6        00110   =>    ..##.

Moving the Block at Y Axis

                  00011         ...##
3<<10 = 3072      00000   =>    .....
                  00000         .....

Combining Block and Board

                  00011         ...##
798|3072 = 3870   11000   =>    ##...
                  11110         ####.

Find full line (using base 32)

                  00011         3
3999              11100   =>    s
                  11111         v

For more information

See the 140byt.es site for a showcase of entries (built itself using 140-byte entries!), and follow @140bytes on Twitter.

To learn about byte-saving hacks for your own code, or to contribute what you’ve learned, head to the wiki.

140byt.es is brought to you by Jed Schmidt, with help from Alex Kloss. It was inspired by work from Thomas Fuchs and Dustin Diaz.