Pixelated surfaces can add a lot of character to a project, giving it movement and visual depth. Any surface can be pixelated, as long as its structural stability isn't compromised. There are different ways to designing a pixelated surface, that vary from strictly superficial to structural.
Tessellation implicates covering a surface with a geometric shape, creating a mosaic. It can be achieved with any shape imaginable, as long as they fit with each other (think of a puzzle with only one kind of piece). This technique has been around for hundreds of years, and it's typical of Arabic and Moorish architecture - it's also two steps away from you, in your bathrooms and kitchens, as square tiling is also a kind of tessellation. This way of pixelating a surface can be achieved with a wide range of materials (stone, ceramic, wood and others), and can be used on any surface. An example of this kind of pixelation can be found on the walls of La Alhambra in Seville, Spain.
Surface perforation makes use of light to create shapes with the help of voids. Usually these pixelations are made on non-structural panels, set in front of the main facade to provide motion and light taming to the building, or inside a building to separate spaces. The most common surface perforation technique involves drilling holes into a metal panel (aluminium, stainless steel, copper amongst others), but can be achieved with any perforable panel such as timber panels and mica panels. Sometimes "perforated screens" are actually screens made of different separated pieces.
Structures can be perforated as well, as long as their perforations are compatible with the building's structural calculations. Concrete structures can be perforated to create pixelations by placing polystyrene shapes into the cast; after the wall is settled and the casts are off, the polystyrene negative shape can be taken away either by burning it or crumbling it to pieces, leaving a void in its place. A famous example of a perforated concrete structure would be Notre Dame Du Haut by Le Corbusier, especially if seen from the inside.
Wooden structures are trickier, especially if you're working with planks and not panels; after perforating wooden structural surfaces you'll have to treat them like window openings, sealing them so they don't leave a void between panels. Masonry walls can be designed to use the separation between blocks to achieve this kind of pixelation; just make sure you don't create structural weaknesses while at it.
Surface fragmentation is a pixelation technique where the pixels are actually part of the structure. It's mostly about texturizing the surface with the material you're working with, either by playing with its composition or its plasticity. Masonry is one of the best materials to create pixels by surface fragmentation, as its components act as puzzle pieces arrangeable in many different ways to create patterns such as chevrons, spirals and even complex combined compositions. Stone can be used to create fragmented pixelation too, using the same principle as masonry pixelation.
In concrete surfaces, a similar treatment can be achieved by texturizing its surface, using casts to make the structure look like it's made of smaller deconstructed pieces. It can also be performed in wood structures, using blocks of wood to create dynamic pixelated facades or surfaces, using principles similar to the ones used in masonry. These wooden pixelated treatments can be part of a non-structural second skin, if the structure by itself is not deemed stable enough.
What do you think about pixelated surfaces? Do you know of other techniques? Leave your thoughts.