Deleted scene from the critically acclaimed film, Gravity.

(Source: ForGIFs.com)

## L-Systems

From Wikipedia

An L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar. An L-system consists of an alphabet of symbols that can be used to make strings, a collection of production rules that expand each symbol into some larger string of symbols, an initial “axiom" string from which to begin construction, and a mechanism for translating the generated strings into geometric structures.

That is a VERY dense definition for something that is more or less simple in nature. In a more simplified nature, and L-System is a set of singular units, and rules to rewrite those units as you process several generations.

A popular example, and one that I found great is the following:

Alphabet: { A, B }
Rule 1: A -> BA
Rule 2: B -> AB
Gen 0: A

What that is, is a very simple L-System. Consisting of just the letters A and B, you follow the stated rules. Every time you spawn a new generation, when you see an A, you replace it with BA, and when you see a B, you replace it with an AB. Very straight forward!

Here are 10 generations of this L-System:

Gen 0: A
Gen 1: BA
Gen 2: ABBA
Gen 3: BAABABBA
Gen 4: ABBABAABBAABABBA
Gen 5: BAABABBAABBABAABABBABAABBAABABBA

Okay, I only wrote down 6, it was becoming painful to continue. I do hope that anyone reading this started to get the idea of what was going on. By following just these simple rules, I was able to create something that’s growing at an incredible rate. As it grows, it also generates a pattern. This pattern that is being generated, if you notice, repeats itself. This is in and of it self one way to generate a fractal.

Fractals are totally out of the scope of this post, but the uses for L-Systems is not! L-Systems have found a great home in the Computer Science world. With memory being dirt cheap, and generation following just a few simple rules. The generation of very realistic foliage and other fractal like structures becomes easier!

Here are the rules for making a fern. They’re fairly complex, but the result is stunning!

variables : X F
constants : + − [ ]
start  : X
rules  : (X → F-[[X]+X]+F[+FX]-X), (F → FF)
angle  : 25°
(Again, thank you Wikipedia)
Result :

Here are a few more cool L-Systems:

What really makes L-Systems really powerful, is how simple they are. They are generated from a simple process, as opposed to being a concrete theory that might lack flexibility. It is a simple process that is powerful enough to emulate the most complex of things in our lives, such as the structure of plants. Go out and you these wonderful structures to make amazing things!

Like the supports to a structure that look like branches! (This was computer generated)

Here is a link to a book dedicated to making foliage with L-Systems.
http://algorithmicbotany.org/papers/abop/abop.pdf

A truly Oscar winning performance.

I’m crying

Love it!!!

i fixed it

(Source: jojoloveswho)

Some motivation from the doctor.

I definitely needed this right now!

I was actually doing homework, love this!

Just what I needed!

Should have added “Now get off tumblr!”

New York City

(Source: nineteenthtime)

Lord of the Rings posters by Blue Rain

The two towers are not Barad-Dûr and Orthanc but rather Orthanc and Minas Morgul jeSUS

(Source: geeksngamers)

9gag:

That’s why I like internet friends…

Deflate when writing prose; inflate when writing essays for school.

Procrastinating on finding ways to add one page to my essay to get the page requirement! Thank you so much.

(Source: amandaonwriting)

Fictitious Dishes, Famous Meals From Literature by Dinah Fried