← Lab homeA faithful recreation of the classic Tetris game where falling tetrominoes are composed entirely of text characters, powered by Pretext's precision layout system for pixel-perfect piece placement and rotation.
What It Does
Tetris × Pretext brings the iconic block-falling puzzle game into the text realm. Players manipulate falling tetrominoes—each rendered as a unique character or character combination—to clear complete horizontal lines and advance through increasingly difficult levels. The implementation is architecturally pure: game state exists independently from rendering, Pretext computes precise layout measurements, and the canvas displays the result without any DOM manipulation during gameplay. The complete experience includes score tracking, progressive difficulty scaling, smooth line-clear animations, and a game-over screen. Every element of the classic Tetris experience translates perfectly to this text-based interpretation.
Technical Highlights
The central technical challenge of Tetris × Pretext reveals Pretext's practical strength: handling rotation when character width is variable. When a tetromino rotates, its visual footprint changes—a horizontal I-piece appears wider than a vertical I-piece because text character dimensions aren't uniform. Rather than computing bounding boxes on the fly, the implementation caches layout measurements for all four rotation states of each piece type during initialization. When a player rotates a piece, the game looks up the pre-computed dimensions, ensuring instant, accurate wall-kick detection and collision response. This approach demonstrates the architectural elegance of Pretext: pure game state feeds through prepare() and layout() to produce precise measurements, which feed into rendering. Canvas rendering is completely decoupled from layout computation, making the rendering pipeline efficient and maintainable.
Pretext APIs Used
| API | Purpose |
|---|---|
prepare() |
Cache layout measurements for all rotation states at game initialization |
layout() |
Compute falling and placed piece positions during gameplay |
Glyph dimensions |
Determine collision detection boundaries accounting for variable character width |
| Canvas rendering | Efficiently render game board and piece state without DOM interaction |
How to Try It
Play immediately at Tetris × Pretext on pretext.cool. Use arrow keys to move pieces left and right, rotate with up arrow or Z key, and drop with down arrow. Clear lines by filling complete rows, and watch your score climb across difficulty levels. The architecture ensures smooth 60 FPS gameplay even with the complex layout calculations required for text-based collision detection.
Built By
Created by shinichimochizuki. Source code available on GitHub. This project showcases how Pretext scales from single-element typography experiments to complex, real-time gaming systems where text measurement precision directly impacts gameplay feel. Visit pretext.cool to explore more about Pretext's capabilities and architecture.
