StepWise
100+ data structures and algorithms, every step narrated with its pseudocode line and variables; step back, share as a link, embed in Canvas.
Apps / Poincaré Paint
Poincaré Paint
Draw in the hyperbolic disk and watch every stroke tile to infinity.
What it does
Draw in the hyperbolic plane and watch your doodle repeat across an endless tiling, like M.C. Escher's Circle Limit prints. Pick a tiling and a symmetry, then paint freehand or with a brush that follows the disk's curved straight lines; every stroke is copied across the whole pattern and thins correctly toward the rim. Drag to travel as far as you like, measure distances and triangle angles, export an SVG, or share your drawing as a link.
Good to know
There is no pinch-zoom on touch screens.
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