Tetris Font

Tetris is among the best-selling (and perhaps best-known) video games ever. We grew up playing the Game Boy and Spectrum HoloByte PC editions. Erik is even a Tetris Master. Nowadays you can play in your browser or on a Switch or on PS4/PC/VR.

Font design. In the default font, each letter and digit is made up of exactly one of each of the Tetris pieces: (I), (J), (L), (O), (S), (T), and (Z). The other selectable fonts use repeated copies of just one piece type. Each glyph is designed so that it can actually be constructed by stacking these pieces one at a time and be supported by previous pieces, as in Tetris. These designs were found by hand, aided by the BurrTools software which enabled searching for whether the Tetris pieces could fit inside a candidate outline for a letter. The piece colors roughly follow The Tetris Company's standard colors, or you can switch to black pieces. The initial rotations follow the standard Super Rotation System.

Puzzles. In the puzzle font, the letters are at the correct rotations and horizontal positions, and their vertical position represents their drop sequence. Drop the pieces in your head (or via animate) to figure out what letter is encoded. • Even without puzzle font turned on, in the animated font, you can try to guess what the letter is before all the pieces have arrived. • One final set of puzzles: In the unanimated unpuzzle black-pieces font, try to figure out how the Tetris pieces perfectly pack that shape. (This is the task that BurrTools is very good at.)

Multiple fonts. You can switch between different fonts in the middle of the text, using these special codes: [7] for one of each piece, [I] for (light), [I2] for (bold), [J] for , [L] for , [S] for , [T] for , and [Z] for . Using different fonts on different lines works especially well. For example, here are all the fonts at once.

Related mathematics. (Perfect-information) Tetris is NP-complete, meaning that it's computationally intractable to figure out whether you can survive, or clear the board, given an initial board configuration and a sequence of n pieces to come. Similar results hold for k-tris played with k-ominoes instead of tetrominoes. We also analyzed the complexity of Tetris with few rows or columns; the original 7-piece font appears in that paper. Most recently, we have explored Tetris with a small number of piece types, first with two piece types and most recently with just one piece type. The latter is the inspiration for the one-piece-type fonts. In particular, we proved NP-hardness for every individual tetromino except , so we have not yet designed a font with just s.

Acknowledgments. The 7-piece font was inspired by a collaboration with Alex Streif and Kate Jones of Kadon Enterprises during BRIDGES 2017, where we started designing a font using just 5 pieces: the “free tetrominoes” where is the same piece as and is the same piece as . Relatedly, Kate Jones designed other polyomino fonts included in some Kadon manuals. By contrast, this typeface aims closer to the rules of Tetris, where reflection matters and the pieces must stack and be supported.

Check out other mathematical and puzzle fonts. • Feedback or not working? Email Erik. • Source code on GitHub.