Piecewise Isometries in 3D

July 17, 2026

drag to orbit · scroll to zoom · right-drag to pan
view
trajectory
parameter spaceα → · β ↓
0.101
0.000
1.000
resolution
500
350
slice
0.00
display
0.015
0.90
0.90
effects
colormap
animate
0.15
0.10
initializing…

About

In flat · 2d view — where this opens — the plotter draws the orbit set of

T(z)={α⋅zif ∣z−2∣>1α⋅(βz+2(1−β))if ∣z−2∣≤1T(z) = \begin{cases} \alpha \cdot z & \text{if } |z - 2| > 1 \\ \alpha \cdot (\beta z + 2(1 - \beta)) & \text{if } |z - 2| \leq 1 \end{cases}

for a single choice of the unit-circle parameters α\alpha and β\beta.

Here we treat each such picture as a slice. Pick a trajectory through the (α,β)(\alpha, \beta) parameter square — sweep β\beta with α\alpha held fixed, or the other way around — and stack the orbit sets along it, at height z=tz = t for trajectory time tt. The union of slices is a 3D point cloud: a bifurcation diagram of the whole family.

The cut controls slice this solid open with clipping planes. A thin slab perpendicular to the tt axis recovers a single 2D fractal; slabs along xx or yy are sections transverse to time, revealing the filament structures traced by the orbits as the parameters move — a view that does not exist in any single 2D picture.

Everything is generated on the fly (a few million points in well under 100 ms) and rendered as an additively-blended point cloud with WebGL.

More about the math (PDF in Spanish)

Juan Pablo Romero Méndez

Juan Pablo Romero Méndez writes about type theory, functional programming, math visualization and proof assistants. @1jpablo1

© 2026