hr-studioPatterns & Tiling · 06
A computational design primer · Penrose Tilings

The pattern that never repeats.

Two simple tiles, laid by one strict rule, cover the plane forever — yet no matter how far you slide the pattern, it never lines up with itself. For decades, mathematicians doubted such a thing could exist. Then Roger Penrose drew it.

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i.

Two tiles, one golden rule

Penrose's tiling needs only two diamonds: a fat one (angles 72° and 108°) and a thin one (36° and 144°). Their sides are all the same length, and their diagonals stand in the golden ratio, φ ≈ 1.618 — the number that quietly governs the whole construction.

Ordinary diamonds would just repeat. These two, forced to obey a matching rule along their edges, cannot.

The two prototiles
ii.

Grow it by splitting

You don't lay a Penrose tiling by hand — you grow it. Every tile is a rule that says how to cut itself into smaller tiles. Apply the cut everywhere, again and again, and an ever-finer, perfectly legal tiling unfolds. This process — inflation — is what guarantees the pattern can never settle into a repeat.

Drag the slider to deflate, step by step.

Subdivide the tiling
iii.

Five-fold, and forbidden

Look at the centre: a perfect five-fold star. Ordinary crystals are flatly forbidden this symmetry — you cannot tile a plane periodically with five-fold rotation. Penrose tilings get away with it precisely because they never repeat. When real materials were found doing the same in 1982, it won a Nobel Prize and a new word: quasicrystal.

Toggle the axes of symmetry through the central sun.

Five-fold symmetry
5 mirror lines · 72° apart
iv.

Patterns inside patterns

Inflation leaves a fingerprint: the tiling is self-similar. Bundle the small tiles back up and they reassemble into the very same two shapes, only larger — and those into larger still, forever. Colour each tile by the big "super-tile" it belongs to and the hidden hierarchy surfaces.

Step the grouping up a level and watch the regions merge.

Super-tiles
v.

The Penrose field

The whole idea, turning gently. Two diamonds, one golden rule, infinite non-repeating order. Push the depth, recolour it, and look as long as you like — somewhere out past the edge, the pattern is still going, and still never repeating.

Scroll to zoom · drag to pan · hover a tile
Order without repetition was supposed to be impossible. Penrose drew it by hand; nature, it turned out, had been growing it all along — just two tiles and one golden rule.