The Peano Curve is one the earliest known FASS-curves. The original algorithm in [pea1890]
bases on one substitution rule and an additional rule which describes how the substitutes have to be connected.
As briefly mentioned in [pau2021]
it is also possible to create the Peano Curve by a substitution tiling with two substitution rules and appropriate decorations.
The inflation factor $q$
is 3 and the lines are shifted slightly away from the center of the sides to illustrate the matching rules.
[Pau2021]
Pautze, S
Space-Filling, Self-Similar Curves of Regular Pentagons, Heptagons and Other n-Gons
Proceedings of Bridges 2021: Mathematics, Art, Music, Architecture, Culture
2021,
38,
157-164,
bridges2021-157.pdf
[pea1890]
Peano, G
Sur une courbe, qui remplit toute une aire plane
Mathematische Annalen
1890,
36,
157-160,
doi.org/10.1007/BF01199438