Settings

Theme

A Topological Picture Book, Rendered

e-infinity.space

147 points by mathgenius · 16 comments

Reader

9 threads
e-infinityspace

This is my project — thanks for the interest. I just made it more mobile / small device friendly.

The app is primarily based on ideas of Hertzmann and Zorin in [this paper](https://cims.nyu.edu/gcl/papers/hertzmann2000iss.pdf), using directions of principal curvature for hatching directions.

  • tobytylam

    Very cool, I made a very primitize plotter before that let you draw on the UV plane and project curves onto the surface (helpful for fundamental groups) / included a time parameter for homotopies. If you're looking for feature ideas I think those would be great! https://tobylam.xyz/3d-plotter

  • throwaway81523

    I only see one picture, the Klein bottle on the front page. Are there more? Maybe it's my browser settings or something like that. Firefox 140.14.0esr. Thanks!

    • throwaway81523

      Oh I see, never mind! You have to use the "preset" pulldown to select different surfaces. I wonder how feasible it would be for other people to add new ones!

  • aanet

    Fantastic project. Love the bells and whistles. I could spend all day here.

    Would love to read a bit on how this was implemented (your stack, techniques, etc).

    Thanks!

  • nxpnsv

    Pretty, and a lot of fun to tweak around the parameters.

sevensor

I was an undergraduate student of George's many years ago and it's an absolute delight to see these renderings. He used to doodle them on any available surface -- blackboards, notebook paper, napkins, what have you -- often with a fountain pen. He was also big into using computers for visualization and had a number of programs that ran in the CAVE.

  • jjtheblunt

    I was a grad student of him, all you describe resonates, and i still stay in touch nearing 40 years later. some of the happiest most fun stuff in grad school, and there were endless nerdy fun pursuits. i'm so grateful i learned under him. it was incredible to see him drawing.

sheept

In addition to making the sidebar dismissable on small screens, it'd be nice to add touch-action: none to the canvas so rotating the object doesn't get interpreted as a scroll on touchscreens.

Right now, at least in Android Chrome, dragging to rotate only works briefly before it's interrupted.

ekzhang

The spacing and style of the hand sketched lines are really perfect. Was it hard get such clean drawings, even using principal curvature fields?

fogleman

Very nice. I've been inspired by the same sources and have always wanted a way to render such drawings for any arbitrary 3D model (e.g. STL file). I've played around with that quite a bit, even recently with LLM assistance, but haven't yet gotten it as good as I want. Eventually...!

mif

Great app to play around with. I thought I can think of the implicit form for a cube. I couldn’t (how embarrassing). It’s:

f(x,y,z) = max(|x|, |y|, |z|) - const.

gotfork

This is awesome, what an incredible project!

ks2048

Is there a way to hide the menu on mobile? The few pixels I can see do look pretty cool.

medwards666

Absolutely beautiful.

Keyboard Shortcuts

j
Next item
k
Previous item
o / Enter
Open selected item
?
Show this help
Esc
Close modal / clear selection