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Show HN: Art – draw one stroke, let symmetry complete it

mrdee.in

86 points by cyb0rg0 · 37 comments

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23 threads
wky

This reminded me of such good memories of playing with http://weavesilk.com/. Nice to see someone with a similar concept.

arist0tl3

The actual drawing experience is really satisfying. A couple usability tweaks I did just fiddling in the DOM: - Put the output and inputs side by side - Put the "actions", export, clear, etc. pinned to the bottom - The overall goal being zero scrolling

After that it was quite fun and I enjoyed the options you gave for things like brush size, metallics, gradients, etc. Nice!

GavinMcG

When I scroll down to select a different color for my next stroke, the canvas often resets.

Edit: or rather undoes the last stroke (which looks like resetting when it goes from 1 to 0).

  • tobr

    Same for me, while the actual clear button, ironically, does not work reliably.

nayuki

I experimented with this concept over a decade ago: https://www.nayuki.io/page/symmetry-sketcher-javascript

I was probably inspired by mouse-painting tools in Corel Photo-Paint (like Adobe Photoshop) that have an "orbits" feature. https://product.corel.com/help/PHOTO-PAINT/540111130/Main/EN...

catoc

Cool!

I made a similar thing for my kids (they wanted something similar to the kaleidoscopic drawing you can do in some ‘Monument Valley’ levels

https://mirror-it.staticdomains.app/index.html

  • detritus

    I bookmarked OP's link for specifically for my kid, but I think she'll much prefer your version, simpler and clearer as it is - thank you so much!

  • andai

    Very cool. I like how it erases the oldest bit as you go along.

  • Wowfunhappy

    I love this!!

fractorial

As a programmer, maths researcher, and painter, there’s certainly something satisfying (to me) when an artistically symmetrical piece observes no mathematical symmetry: The very asymmetry in the language used to describe it is, in and of itself, beautiful.

  • gilleain

    Not sure what you mean by "an artistically symmetrical piece observes no mathematical symmetry" - as in, the underlying structure has a (set of) symmetries but the 'decoration' on top is asymmetric?

aaroninsf

Suggestion OP if you would like one:

Support click-and-spin with momentum: I clicked outside the mandala and quick-dragged horizontally, hoping this would spin the mandala.

You could support zero-friction and momentum, slowly stopping.

In either this unlocks a dramatically new aesthetic: clicking on the rotating surface draws splines. The mapping of gesture-to-line (hence mandala elements) changes completely.

There are some complications, intuitively one might expect "pottery wheel mode" where symmetry is not enabled... I think that would be "unlearned" however.

andybak

Ha! I added a similar feature to Open Brush: https://docs.openbrush.app/user-guide/multimirror

And learned a bit about group theory in the process... :-/

( https://github.com/IxxyXR/unity-symmetry )

larodi

Hm... is this technically a mandala? I mean - does it suffice for something to have radial symmetry to be called a mandala?

intrasight

Feature request it would be fun to draw snowflakes but to do that there'd have to be another setting to constrain things you draw to be straight lines at just the angles that ice crystals would allow.

smusamashah

The control panel should have been on the side instead of below the image. I scroll to bottom, mandalla disappears on top in the screen, I click generate, then I scroll back up, repeat.

VVIQ2

Nice! Kinda reminds me this: https://en.wikipedia.org/wiki/Spirograph

dmd

Love this. I had something almost identical on my Commodore 64 40 years ago that you could use with the joystick or KoalaPad.

albinn

Cool! I got a weird feeling when playing with it, it's just something very satisfying in seeing it be completed

timbaiguzhinov

Even with the perfect math, i made it ugly, lol. But it got me hypnotized, spent 10 minutes in a blink of an eye.

kazinator

I'm like:

Neat! I will show this to my small kids.

Wait, nope; they already know how to make mandala coasters offline with scissors and paper.

thraxil

"Mirror" mode was my favorite feature on the Koala Pad app back in the 1980s.

fiskeben

I spent a lot of time playing with a similar tool in Deluxe Paint as a kid.

aghilmort

lots of fun! like etch-a-sketch, lite-brite, spirograph, paint, etc. on steroids!!

Gualdrapo

fwiw Krita has a similar setting in its brush tool - you draw a stroke and said brush stroke is mirrored by a given x axis or a given y axis (or both)

abhishxk1

Bro this is hypnotic lol i spent 15 mins on this without even realising

OttoZ05

we clearly need the mobile app

  • Jaxan

    I looked in the AppStore for “symmetry draw”, and there are at least 10 such apps.

aussieguy1234

Now we just need the mobile app

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