**Even though the t-tetromino in the Tetris logo is not split into four minoes. *As of 2009, if hardware limitations do not allow all colors to be used, tetrominoes have distinct hues and patterns to differentiate themselves. Other names include straight, stick, strike, line, long bar, vav (or vov, waw), final nun, one, the cyan piece, the long skinny one, the slim jim, tetril, TGM-red, hot shot, long, slim dandy, the flashmaker, long boi, big poppa, thin lizzy, stack-em-up, Euclid's Arrow, four on the floor, George and hero.ĭue to I's design as a Tetromino, it can be used for a Tetris Line Clear, because of a design of 4 Mino's (Blocks) tall. This tetromino is very useful for filling deep 1-wide wells within your stack (Diagram 1), and is the only one to be able to clear 4 lines (a Tetris) within traditional rulesets (Diagram 2). If you know any other names for a tetromino, please list them in the section corresponding to the tetromino by editing the section. Tetris is still patented today, and the patent will expire in 2032. Another patent application was submitted in 2012. They were patented in 1996, but it expired two decades later. The idea of tetrominoes is copyrighted to them. The Tetris Company owns the copyright and trademark on all seven tetrominoes. The diagrams below will use the guideline colors. Since then, the color schemes associated with SRS and TGM Rotation have dominated new games, and 'the blue piece' is always J (see below). However, before about 2001, these colors varied from product to product, making it difficult for people who play different games to discuss 'the blue piece'. Mario, or black-and-white systems*, each tetromino has a different color. In most games other than Tetris for NES, Tetris & Dr. In the text diagram, the top layer is on the left, and the bottom layer is on the right.ġ.) 2×4×5 box filled with two sets of free tetrominoes:Ģ.) 2×2×10 box filled with two sets of free tetrominoes:ģ.) 2×4×4 box filled with one set of all tetrominoes:Ĥ.) 2×2×8 box filled with one set of all tetrominoes:ĥ.Each tetromino has a letter name and several alternative names. The text diagram depicts each set as having a capital or lower-case letter. For boxes using two sets of the same pieces, the pictorial diagram depicts each set as a lighter or darker shade of the same color. They are shown in both a pictorial diagram and a text diagram. The tetracubes can be packed into two-layer 3D boxes in several different ways, based on the dimensions of the box and criteria for inclusion. This was discovered by exhausting all possibilities in a computer search. Additionally, the 19 fixed tetrominoes cannot fit in a 4×19 rectangle. By extension, any odd number of sets for either type cannot fit in a rectangle. Similarly, a 7×4 rectangle has 28 squares, containing 14 squares of each shade, but the set of one-sided tetrominoes has either 15 dark squares and 13 light squares, or 15 light squares and 13 dark squares. This is due to the T tetromino having either 3 dark squares and one light square, or 3 light squares and one dark square, while all other tetrominoes each have 2 dark squares and 2 light squares.

A 5×4 rectangle with a checkerboard pattern has 20 squares, containing 10 light squares and 10 dark squares, but a complete set of free tetrominoes has either 11 dark squares and 9 light squares, or 11 light squares and 9 dark squares. This can be shown with a proof similar to the mutilated chessboard argument. Tiling a rectangle Filling a rectangle with one set of tetrominoes Ī single set of free tetrominoes or one-sided tetrominoes cannot fit in a rectangle. S: two points of rotational symmetry only.Square: vertical and horizontal reflection symmetry, and four points of rotational symmetry.Straight: vertical and horizontal reflection symmetry, and two points of rotational symmetry.The free tetrominoes have the following symmetry: A free tetromino is a free polyomino made from four squares. That is, two free polyominos are the same if there is a combination of translations, rotations, and reflections that turns one into the other. A free polyomino is a polyomino considered up to congruence. Polyominos are formed by joining unit squares along their edges.

The tetrominoes used in the game are specifically the one-sided tetrominoes. The corresponding polycube, called a tetracube, is a geometric shape composed of four cubes connected orthogonally.Ī popular use of tetrominoes is in the video game Tetris created by the Soviet game designer Alexey Pajitnov, which refers to them as tetriminos. Tetrominoes, like dominoes and pentominoes, are a particular type of polyomino.

Four squares connected edge-to-edge The 5 free tetrominoes A snapshot from a typical game of Tetris.Ī tetromino is a geometric shape composed of four squares, connected orthogonally (i.e.

Original tetris blocks