Inigo Quilez   ::     ::  
1402 blog posts, written between 2008 and 2016. These are mostly short observations, funny thoughts and word playing. Some are embarrasingly corny, some more deep. I keep it here mostly a little time capsule for myself, organized by month:

October 2014
live can't get much better
if you have walked in sanfran today... in the morning, under this beautiful sun, under this gorgeous sky, you have fallen in love with the city for sure.

perfection is a word for excellence, precision and correctness. there needs to be another meaning for perfection, one with connotations of blessing, and that expresses joyfulness. and then i'd use it to describe this morning walk in downtown in which, indeed, i've fallen in love with the city again.

live can't get much better than this.
propaganda. really?
how amusing it is that when data aligns with our believes (and learnt truths) it is called "information", but when it doesn't it becomes "propaganda"

on delusions and learnt truths
i've been using this word for a while.

like "huggable". but when i recently heard the word "huggable" in a movie i got so sad and disappointed, because it felt like i had been stolen my word.

of course, english is not my language, and i should realize that chances are little i invent and keep ownership my own words like i do in spanish.

when i heard "huggable" in that movie, i immediately feared that my beloved "prettiful" wouldn't be mine either, as i believed it was. and indeed, google revealed that many people are using it already out there.

still. i'll keep using them, i think "prettiful" and "huggable" are prettiful words.
mixt greens? mixt meats, please. asap
glad, but also disappointed
when it comes to bed sizes, i was aware of the usual "twin", "full", "queen" and "king" names. but today i learnt there's something called "california king".

of course, knowing californians, all i could think of at first was a massive swimming pool sized bed with the photograph of arnold schwarzenegger printed in it on which you have to roll for 5 minutes before you find your partner in it. "that's what California King must be", i though.

however it seems it's not that crazy at all - in fact it's just a king size with a slightly different aspect ratio. i'm glad. but also slightly disappointed.
mathimage: antialias
Another very quick doodle during dinner based on a previous mathimage. This time the emphasis was into getting cheap antialiasing working, and little more. It was a fun one! Realtime animated version, and open source code, here:

so rare!
today i met an american who's name was longer than two syllables
lol information lol science lol
i read an article today with its title beginning with "Psychologists Find...", which i read cause i found the announced findings really interesting, for their deep social impact. then half way the read, the article which seemed otherwise to be describing a legit study, revealed that the researchers have used a set of 110 people in their study.

now, i'm not a psychologist myself, but i am pretty sure that a population of only 110 samples, with no control group and certainly not sociocultural diversity is not considered a good enough group to extract conclusions AND publish them online for all us to read.

just cause i can find 110 people who own a car who can't drink milk, it doesn't mean i can publish an article "New Research Finds Owning A Car Increases Lactose Intolerance". that's not how science works.

who the hell is conducting these experiments and who's allowing them to be published? and how did this end in my feeds?
fractals everywhere
Somebody in the very depths of the most apocalyptic part of the city's decadent neighborhood, in a dark street hidden between shadows I find a house door protected unlike other doors. Rather than the usually security bars (yep, I know, doors with security bars...), this door has a design that my brain's pattern recognition circuitry matches to some memory of mine from the past. It's a familiar shape, a mathematical figure from my late teenage back from when coding fractals was my obsession. Once this parasympathetic alarm reaches my consciousness, I halt, turn around and look to the door. The doors motive is made after the bifurcation diagram of the Logistic Equation in the complex plane, which being a quadratic map, is holomorphic to the Mandelbrot Set (and it resembles it indeed). These are objects related to Fractal geometry and the Chaos Theory, trendy back in the 90s among computer aficionados. You might remember some of these words from Jurassic Park or from hippie american university teachers from those times.

I find it amusing that the designer of these door bars, and the owner of this house too, decided to honor this mathematical object. I also find amusing that I accidentally found it here, in the darkest corner of this (one must admit, very nerdy, city). 15 years later.

Inspired by the discovery, I run home and I code the fractal, which corresponds to the formula z -> h.z.(1-z), as if I was that 19 years old boy again. Only that this time I derive the formula for producing a smooth/continuous coloring in its exterior based on the Hubbard-Douaddy potential theory. Unlike when I was a late teenager, now I do have the maths knowledge to do so (although I am not as fluent as when I was at university).

The formula for the coloring is color = n - 1 + log2( log2|z| + log2|h| ), and this the realtime rendered set, together with the Logistic Map bifurcation diagram in real numbers superimposed (note how the bifurcation points alight with the periodic components of the fractal set):
one baby, two babies
as we all know, if there's one kid/baby in the plane, (s)he becomes the dictator of the plane - by the power of crying (s)he decides when everybody else sleeps.

when there are two kids/babies in the plane... i have just learnt that they cancel each other (get tired of each other's crying, indeed) and both fall asleep. and so can do the rest of us.

i feel they got it wrong
I just read this article where they try to explain what the privileges of being born in a wealthy (white) family are (I'm surprised this needs to be explained in the first place, but ok), and how it affects the american dream, which is, and I quote straight from the article, "everyone in the country has a chance to become wealthy and move into the upper class.”

I think this dream is pretty fucked up, and at the same time so internally accepted that these people don't see the problem. To me, this ill-formed dream has already established that society will be divided in an lower and an upper class. As an axiom. I might be wrong, but as far as I understand the dream is not about having a wealthy and healthy country for all to enjoy, but to have equal opportunity to escape the crappy lower class and saves themselves into the upper class. Basically, the dream is not to get rid of classes, but to be the one to be in the cool group (and "fuck the others").

This article I just read aspires to open the eyes of those already in the privileged group by explaining to them how unfair it is that simply by being born in the right group they enjoy the luxury of encountering less obstacles to reach or stay in the social safety zone. And compassionate as the writer seems to think (s)he is regarding the lower class, the article totally misses the deeper unfairness, the real problem, the big elephant in the room.

I'll copy&paste again, for your brain to shiver: The greatness of this country is that "everyone in the country has a chance to become wealthy and move into the upper class.”. Some are even proud of this. And that certainly makes this country unique. Not the way they think, though.

I sometimes feel these people got it wrong.
mathimage - repulsion
because repulsion can be attractive.

quick doodling on sphere again, but in this case on their dynamic, not their appearance.

making sphere repel each other in a stateless system where concepts such as force, acceleration and velocity don't really apply (in their traditional sense of numerical integration).

click in the link to see the spheres repel each other in real time and to explore the code/maths involved in the animation/image:

on premature noise art
in computer graphics coding, often times bugs manifests themselves as artifact of no little visual interest. it is really tempting to explode the bug and develop some semi-interesting visuals. and it can be an interesting exercise. in fact, i have a few times seen experienced art coders encourage young aspiring programmers use their bugs to create art.

however... i think this is not a good idea in general. and giving that advice can mislead the young apprentice.

sure the broken image it looks interesting. but the problem with bug-art is that most of the times the coder doesn't understand the bug and hence the code/algorithm. and if one doesn't understand it, one cannot control it. if you cannot control it, is it legitimate art? what's the value of the art that you cannot direct? regardless this question, from a pure technical perspective, not being able to control your paintings/algorithms makes a poor graphics programmer.

once a bug happens and a visually interesting artifact emerges as a result of it, i think the best thing to do is to take a snapshot of the code/image, but keep moving and fix the bug. learn to control the image to be what (s)he wants. there will be time (and more creative resources) to make an image interesting (especially if it's noise art) later in the game, no worries.
stop it already
zoos. a concept from the 19th century.

i do understand that kids (and adults alike) from the London of 1850s had never seen an alive giraffe or an elephant in their lives, not even a moving picture (film) of them. i do understand that people would run to the zoo to see these fantastic creatures only seen in book drawing that were so different to the cows and sheep they were used too. and because of that, i do understand that zoos were visited every day.

but these days... we all have seen these animals in TV and in movies. so, can we stop going to the zoos. in fact, can we please stop having zoos altogether, and leave the animals where they belong?

if you are a city kid and feel like seeing animals alive, go to the country side and see a cow (have you ever seen, or milked a cow, city kid?). or if you really feel like seeing an animal from the savanna, go for a visit there and leave some money to fund the protection of their habitat.

stop going to the zoos. those things should most probably not exist.
because i want so
Because we are all encouraged to do things the way we know they work, because reinventing the wheel is something we are supposed to avoid and because being stubborn is seeing as a bad quality... I often decide to hold to my believe that revisiting old stuff my lead to new ways to do things. Because I want so.

In doing so, sometimes, I do find, indeed, new ways to do things. Such as, rendering analytically antialiased spheres with analytical plausible soft shadows and occlusion.

Analytical in this case means not using montecarlo integrating any of these three forms of visibility. Or in other words, noise free, pixel perfect, light-speed images. Sure spheres are special, so what. They are cute too. So the time spent in paper and pencil with the formulas was totally worth it.

Realtime version and code/math, here: