Editing Tetromino (section)

==Filling a box with tetracubes==
Each of the five free tetrominoes has a corresponding tetracube, which is the tetromino [[extrusion|extruded]] by one unit.
J and L are the same tetracube, as are S and Z, because one may be rotated around an axis parallel to the tetromino's plane to form the other. Three more tetracubes are possible, all created by placing a unit cube on the bent [[Tromino|tricube]]:

{{multiple image 
| align=left
| image_style = border:none;
| image_gap = 25
| image1 = Tetromino I.svg
| width1=71
| caption1 = I <br>"straight tetracube"
| image2=Tetromino O.svg
| width2=39
| caption2=O <br>"square tetracube"
| image3=Tetromino T.svg
| width3=54
| caption3=T <br>"T-tetracube"
| image4=Tetromino L.svg
| width4=56
| caption4=L <br>"L-tetracube"
| image5=Tetromino J.svg
| width5=56
| caption5=J is the same as L in 3D
| image6=Tetromino S.svg
| width6=56
| caption6=S <br>"skew tetracube"
| image7=Tetromino Z.svg
| width7=56
| caption7=Z is the same as S in 3D
| image8=Tetracube branch.svg
| width8=41
| caption8=B <br>"Branch"
| image9=Tetracube r-screw.svg
| width9=42
| caption9=D <br>"Right Screw"
| image10=Tetracube l-screw.svg
| width10=39
| caption10=F <br>"Left Screw"
}}

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. They are shown in both a pictorial diagram and a text diagram. 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. The text diagram depicts each set as having a capital or lower-case letter. In the text diagram, the top layer is on the left, and the bottom layer is on the right.
 
[[File:Tetromino_tetracube_packing.svg|right|325px]]
<pre style="margin-left:2em;">
1.) 2×4×5 box filled with two sets of free tetrominoes: 

Z Z T t I        l T T T i
L Z Z t I        l l l t i
L z z t I        o o z z i
L L O O I        o o O O i





2.) 2×2×10 box filled with two sets of free tetrominoes:

L L L z z Z Z T O O        o o z z Z Z T T T l
L I I I I t t t O O        o o i i i i t l l l





3.) 2×4×4 box filled with one set of all tetrominoes:

F T T T        F Z Z B
F F T B        Z Z B B
O O L D        L L L D
O O D D        I I I I





4.) 2×2×8 box filled with one set of all tetrominoes: 

D Z Z L O T T T        D L L L O B F F
D D Z Z O B T F        I I I I O B B F





5.) 2×2×7 box filled with tetrominoes, with mirror-image pieces removed:

L L L Z Z B B        L C O O Z Z B
C I I I I T B        C C O O T T T
</pre>