Origami: Passiflora Ornata

Passiflora Ornata

Passiflora Ornata, designed by Ekaterina Lukasheva

This month, I checked my photo folder for any Christmas-oriented models.  Here’s one, from the days when I couldn’t take good photos, lol.

As you can see, there are four colors of paper: Green, Red (with a white back), silver foil, and patterned green.  The silver foil and patterned green are just small squares inserted directly into the model.  When most people look at this, they think, “Shiny!” but when I look at it I think “Inserts are such a good idea, I should use them more often!”

Origami:, sourced from Eric Gjerde’s Origami Tessellations, which credits it to Shuzo Fujimoto.

This month, I felt like posting one of my really old models, this one made in *checks notes* 2014. This is surely one of the very earliest tessellations I tried making.  But surely this was after practicing a few times, because these aren’t exactly a cake walk to make.

Providing a back light for the tessellation illuminates its structure.  The tessellation consists of a series of hexagonal twists and triangular twists.  Adjacent twists are connected by pleats, which are darker because the light is going through three layers of paper instead of one.

I looked up the symmetry group, and I’m pretty sure this is p6 wallpaper group.

Origami: Orthogonal maze

it's not really a maze, since there's no clear entrance or exit

Orthogonal Maze, designed by Erik Demaine, Martin Demaine, and Jason Ku

Okay, so it’s not much of a maze, but you know, it could be.  There are detailed instructions on how to fold any orthogonal maze, and even a web-app that will generate crease patterns for you.  I gave it a go, with a small (15cm) square of paper.  I wasn’t going to manage much of a maze with this size, so I just made something symmetric instead.

My impression is: it’s hard!  I’m not confident I would be able to fold a larger maze by this method.  The issue is that some of the maze components are really difficult to fold, and some of the others pull apart too easily.  I think if I wanted to fold something larger, I’d try to workshop the design a little more, or find a different method.  But I also made this years ago, so maybe if I tried again I would be better at it.

Origami: wobbly cube

Wobbly cube

Wobbly Cube, a one-shot design by me

This was one of my experiments in curved creases.  I basically cut out 12 identical S-shaped strips (with ruler and compass), and then creased them along their centers.  Then I quickly invented a scheme for secure attachment.  Not much more to say about that.  I like how it turned out.

Origami: Octopus 2

Octopus, by Sipho Mabona.

Back in 2016, I made an octopus and posted it here on A Trivial Knot.  Now I’m showing my second attempt, which was made two years later.  With more experience, I was able to make a more elegant octopus, while also using foil paper (which is generally harder to work with).  I was quite satisfied.

Although… if I want to pander to a certain someone maybe I ought to switch to spiders.

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Origami: Six intersecting pentagonal prisms

Six intersecting pentagonal prisms

Six intersecting pentagonal prisms, designed by me.

I might be less active this month, so I thought I’d make up for it with an origami model you can dig into.  This model is called “Six Intersecting Pentagonal Prisms” because it’s literally made from six pentagonal prisms.  I’ve got some photos below the fold showing the step by step addition of each pentagonal prism.

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On color theory

This is a repost of an article I published on Tumblr in 2017.  As many things I publish there, it was written somewhat extemporaneously, but it stood out as something I wanted to eventually import here.

There are really two color theories, the scientific theory of color perception, and the aesthetic theory of choosing color palettes.

The former is quite interesting, containing some surprising facts: yellow is the brightest color, many shades of green can’t be produced by modern displays, white is defined arbitrarily.

The latter is a hodgepodge of various historical ideas and a collection of overgeneralized advice. When I’ve read about aesthetic color theory online my impression is that much of it is either already taught to children or else it is not very good. Here is my attempt to identify some non-bullshit principles of color theory.

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