Wednesday, April 29, 2009

Back from vacation

I'm back from vacation, and after some intensive days catching up on everything. I believe I'll be able to continue working on the book within a week, and I hope to have a draft of the first chapter by the middle of May. I also some ideas on changing the table of contents.

I should also mention that I didn't fold much during my vacation. I forgot my origami papers, and surprisingly, paper was very hard to find. Next time, I'll check out Ilan's page before I pack...

Tuesday, March 24, 2009


I'll be on vacation with little or no internet access until April the 18'th.

The first chapter of the book is nearly complete, and I will publish it once I'm back.

Friday, March 20, 2009

Crease Patterns eBook

Over the coming weeks (and months), I will be writing an ebook about how to fold crease patterns, which will be freely available once it is complete. I will post the work in progress chapters in this page as I write them, which will give everyone a chance to review and comment on them before the final "official" publication. Be sure to bookmark or sign up for the rss feed to receiver updates when new chapters are available.

Table of Contents
  1. Introduction - Quick example, Why Bother, History
  2. How to Learn
  3. Four "'Easy" Steps - Finding the reference points, Folding the creases, Collapsing and the Final Touches.
  4. Finding the Reference Points - Overview, Common Patterns, Using Reference Finder, Example Models
  5. Folding the Creases - Overview, Top to Bottom Approach, The Importance of Symmetry, Common Patterns, Example Models
  6. Collapsing - Overview, Common Patterns, Example Models
  7. Final Touches - Overview, No More Words
  8. Other Resources
  • Appendix - Catalog of common patterns

Saturday, February 28, 2009

Folding the Peacock from CP

In this article I will show how to fold the Peacock from its crease pattern, with (hopefully) some useful advice on crease-pattern folding in general given along the way.

Before we begin with the actual folding, here's a quick recap of the steps that need to be taken whenever we fold from a crease-pattern:
  1. Identify the reference points
  2. Fold all the creases
  3. Collapse the paper into the base
  4. Fold the finishing touches
For a more detailed explanation, you can see this article on crease patterns.

So lets start by opening the peacock's crease pattern in another window (or, you can print it, if you're not ecologically consciousness). This model is not too difficult to fold from a crease pattern, and yet it is not trivial, which makes it a good model to learn from, in my opinion.

Step 1 - Identify the reference points

If we look at the crease pattern, we will hopefully recognize the creases on the bottom left half of the page as the creases which make up part of the bird base. If you don't recognize it yet - don't worry! Most crease patterns are made up of "blocks" of common patterns. If you wish to learn how to fold from crease patterns, you should get into the habit of unfolding the common folds you encounter when folding from diagrams. With time and experience, you'll be able to connect these patterns to the folding sequence that create them. You should start by learning to recognize the patterns of the basic bases, such as the bird base.

Okay, so we recognized that half of this model is a bird base, and this gives us all the reference we need to start folding. In other models, this step can be more difficult, and I'll leave it for a future article.

Step 2 - Fold all the creases

We already know how to fold half of the crease pattern, and that's a great start. So, let's begin by folding it. There are, however, some things to note. For example, when folding the bird base, you'll introduce some creases which aren't marked on the crease-pattern. This is OK. The crease pattern only shows the creases which will be in the final base, and not any of the intermediate creases. It's OK and most of the time necessary to make creases which aren't on the crease pattern. This may be confusing because it will be harder to compare your paper to the crease-pattern. If this is the case, then you can mark with a pen the creases which will comprise the final base. Remember - the first fold is a practice fold, and everything goes, even scissors (again, part of a future article).

One last note before we finally start folding - one of the creases you'll most likely introduce in this stage is the second diagonal, which isn't part of the crease-pattern. It's import to note that this a major symmetry line - that is, if you fold along this line, all off the crease on one half of the page will lie exactly on top of all the creases on the other half of the page. There are many such lines in this crease pattern, but this diagonal is the biggest, and therefore the most important. Recognizing these lines can be a big help when folding the creases to the paper.

So, let's fold!

Here is how the folded "model" looks, and how it looks unfolded. You can see that we finished nearly half of the crease pattern. Yay!

Now, we'll start looking at the other, more challenging half of the crease pattern.

Whenever we're not sure how to proceed, it is usually best to look for the biggest creases we haven't already folded, and start with them. In this case, those are the two parallel diagonal lines which end up all the way in the bottom left half of the paper, near the center. So, let's fold them. These creases are perpendicular to the major diagonal crease. This means that we want to take the top left corner, and start sliding it along the diagonal until the crease line passes through the existing crease near the center.

Now, if we look again at the crease pattern, we'll see that there are two triangles we need to fill with creases. After a bit of practice, we'll recognize these creases to form an inside reverse fold. So let's fold them, and then we'll be nearly done.

Again, we look for the biggest creases we didn't already fold. They are again diagonals parallel to the major axis. They fold in half the creases in the top right flap. We fold them, and then add the creases in the center of the paper.

Done! We have all the creases in place!

Step 3 - Collapse the paper into the base

Collapsing this base is a bit tricky, but I don't want to spoil too much of the fun of discovering things on your own. After all, the best way to learn is by doing. But, you do have all the creases in place, and you already know how to fold half of the model. The base looks like this:

Step 4 - Fold the finishing touches

The final stage to folding the model is to take the base and convert it into the finished model. Sometimes, this is easy. At other times, this may be difficult. I've already identified which flap becomes what, and that's the first step to understanding how to finish the model. In any case, a picture of the finished model is useful. I won't include one here, because this is where you can let your creativity take over. You don't have to do exactly what the original author did. All the building blocks are in place, and you can do with as you wish.

One Last Note
As I said before, the first try is a practice fold. The way you fold a crease pattern the first time is very different from the folding sequence as it would appear in diagrams. There is a much nicer folding sequence for this model, and you can develop your own after you understand how to fold the model.


Note: If you have questions, please use the comments below. This will allow future readers to know about these problems and their solutions.

Friday, October 31, 2008


"It is practically impossible to teach good programming style to students that have had prior exposure to BASIC: as potential programmers they are mentally mutilated beyond hope of regeneration."
Edsger W. Dijkstra (SIGPLAN Notices, Volume 17, Number 5)

If you think about it, and please do just that right now, then you'll probably notice that you use your native language to facilitate the thinking, at least to some extent. Taking this observation to the next step, how much does our native tongue influence our thought patterns, and how we perceive the world around us?

This is not a new question. There's even a theory in linguistics which studies this question, called the Sapir Wohrf hypothesis. In fact, George Orwell, in his classic book "1984", has a whole new dialect, "Newspeak", introduced by Big-Brother to aid in preventing "thoughtcrime". This imaginary language is unique in that it attempts to reduce its vocabulary, thus intending to limit thinking patterns.

A couple of years ago I heard a lecture (in hebrew) by Physicist turned Computer-Scientist, Prof. Naftali Tishbi, on some of the research he's conducted on languages and their affect on thought (and vice-versa). Since then, the subject has been sitting in some corner of my brain.

A couple of examples:
  1. When a procedure that I already know is coined, I can understand and use this procedure much more easily. For example, in Origami, the term "Double Rabbit Ear" allows my brain to much more easily choose an appropriate course of action, rather than just remembering some sequence of folds I've done before. In programming, that's exactly what Design Patterns do. I've used the Factory pattern before, but coining it made it more accessible cognitively, and it's now much more easy to notice when this pattern is appropriate.
  2. When attempting to solve a programming challenge, the choice of language affects the solution. This is taken to a very interesting extreme in LISP, where the first step to solving a problem is to create a new language tailored specifically for it.
There is no doubt that what programming languages a developer knows critically affect the quality of the solutions he'll be able to come up with. Until I learned Perl, I wrote simple text processing tools in C. The results were buggy programs which took too much time and thought to write.

But it is much deeper than this. A programming language affects how we even think about problems. Knowing several programming languages is important in developing our own minds and allows us to better think about problems. This is not new. Edsger W. Dijkstra already talked about this in his excellent 1972 lecture, "The Humble Programmer".

So, my resolution for the following year is to learn two new languages. While I think I know enough of Perl to get what I want done, I'm no expert in it, mainly because I don't like too many $ and too few letters. That's why I'm going to spend the next year studying Python. And I intend to really study it, inside-out.

I have a full-time job, a wife, some non-programming hobbies, an obligation to write a computer game, but I intend to follow through.

Funny comic from, August 15, 1999

The other language I'll be learning is Japanese, by the way.

Tuesday, September 2, 2008

New Origami Diagrams

New Origami Diagrams

I have uploaded many of the diagrams for models by Yehuda Peled, diagrammed by him, which were hosted on the old Origami Tips website, and who had no internet location since that site went down.

You can find them in the diagrams section.

Thursday, August 21, 2008

Origami Diagrams and Crease Patterns

These are some of the old diagrams from the old Origami Tips website:

Ninja - intermediate
Peacock (cp) - intermediate (see here for article explaining how to fold)

Models designed and diagrammed by Yehuda Peled
Bee Orchid
Stem for Daffodil
Long Neck Bird
Orchis Anatloica
Pentagon from A4
Pentagon from Square
Stem and Leaves
Tripod Stem