Sunday, May 31, 2009

Pixar's work finally slides into the Uncanny Valley

There's a hypothesis in animation called "The Uncanny Valley".. It states that something featuring live characters becomes more realistic, it for a while becomes more enjoyable. Then it suffers from something called The Uncanny Valley, where becoming more realistic makes it more creepy.

Pixar's work was always the coolest to me because I thought it successfully stood atop the "stylized" peak right before the Uncanny Valley.

*micro spoiler alert*

There are dog crowd scenes in the new movie, Up. They have one main character dog who is very stylized in construction (and featured in the TV commercials). But there is a plot conflict between this dog and a crowd of other dogs, many of which are much more photo-realistically constructed.

When there's one photo-realistic dog on the screen, emoting, it seems pretty cool. But there are scenes when they show a dozen, and because they are photorealistic, they look like zombies. I think there are both creepily over-acting dogs and creepily wooden dogs in a few scenes in the movie.

I've always bristled in animation when critics demand photorealism. I think that these critics don't understand the Uncanny Valley hypothesis.

Pixar UP Full Length Movie Trailer - HD High Quality - The best bloopers are here

Saturday, May 30, 2009

Space Drama!

Here's a video from a young man who's just like me, in that he's making movies for the web and wondering if there's a business model in it. Only he's half my age, doing video, per se, and has talent. I found his blog very interesting.

Thursday, May 28, 2009

Draft of IRTC pre-round entry

Draft of IRTC pre-round entry, originally uploaded by pterandon.

This isn't quite finished-- notably the hands of my main character are undergoing a major revamping. I was almost about to post this to the IRTC web page as it is.

Monday, May 25, 2009

Conservatives' one-sided citation of tradition makes tradition look bad.

On this Memorial Day, when we honor those who have sacrificed for our country, I've already seen on the internet two conservative Christians cite classic texts from church tradition to diss pacifism. As if the only lesson we get from the church historic, from church tradition, is that you shouldn't be a pacifist. I'll take the risk of offending my pacifist brethren by saying that I don't think there's a whole lot in the tradition of the church to support a pacifistic view.

At the same time, I think it's a bit tragic to take some of these classic texts and only quote one side of it. Not only have we received some very good reasons not to be pacifist, we've also learned why warmongering is bad. Sometimes the two lessons come in the same epistle or tract. To only quote one message is to reduce the witness of the church to propaganda. The saint who comes out to silence Caesar's critics, but doesn't challenge Caesar is something of a court prophet. All mouths are to be silenced, for all have disobeyed.

I've often seen conservatives quote Martin Luther's "Whether Soldiers, Too, Can be Saved." But they only quote the parts that attack pacifism. Here is one of them. (I'll also admit that this document from Luther helped me see the problems with pacifism):

The complete text of "Whether Soldiers" can be found if one searches the Table of Contents of this document at Google Books.

"As proof, I quote John the Baptist, who, except for Christ, was the greatest teacher and preacher of all. When soldiers came to him and asked what they should do, he did not condemn their office or advise them to stop doing their work; rather, according to Luke 3 [:14], he approved it by saying, "Rob no one by violence or by false accusation, and be content with your wages." Thus he praised the military profession, but at the same time he forbade its abuse. Now the abuse does not affect the office. When Christ stood before Pilate he admitted that war was not wrong when he said, "If my kingship were of this world, then my servants would fight that I might not be handed over to the Jews" [John 18:36]. Here, too, belong all the stories of war in the Old Testament, the stories of Abraham, Moses, Joshua, the Judges, Samuel, David, and all the kings of Israel. If the waging of war and the military profession were in themselves wrong and displeasing to God, we should have to condemn Abraham, Moses, Joshua, David, add all the rest of the holy fathers, kings, and princes, who served God as soldiers and are highly praised in Scripture because of this service, as all of us who have read even a little in Holy Scripture know well, and there is no need to offer further proof of it here. Perhaps someone will now say that the holy fathers were in a different position because God had set them apart from the other nations by choosing them as his people, and had commanded them to fight, and that their example is therefore not relevant for a Christian under the New Testament because they had God's command and fought in obedience to God, while we have no command to fight, but rather to suffer,endure, and renounce everything. This objection is answered clearly enough by St. Peter and St. Paul, who both command obedience to worldly ordinances and to the commandments of worldly rulers even under the New Testament [Rom. 13:1–4; I Pet. 2:13–14]. And we have already pointed out that St. John the Baptist instructed soldiers as a Christian tteacher and in a Christian manner and permitted them to remain soldiers, enjoining them only not to use their position to abuse people or to treat them unjustly, and to be satisfied with their wages. Therefore even under the New Testament the sword is established by God's word and commandment, and those who use it properly and fight obediently serve God and are obedient to his word.

At the same time, there are also some pretty resounding denunciations of rushing to war:

At the very outset I want to say that whoever starts a war is in the wrong. And it is only right and proper that he who first draws his sword is defeated, or even punished, in the end.

Wait until the situation compels you to fight when you have no desire to do so. You will still have more than enough wars to fight and will be able to say with heartfelt sincerity, "How I would like to have peace. If only my neighbors wanted it too!" Then you can defend yourself with a good conscience, for God's word says, "He scatters the peoples who delight in war." Look at the real soldiers, those who have played the game of war. They are not quick to draw their sword, they are not contentious; they have no desire to fight.

Let this be, then, the first thing to be said in this matter: No war is just, even if it is a war between equals, unless one has such a good reason for fighting and such a good conscience that he can say, "My neighbor compels and forces me to fight, though I would rather avoid it." In that case, it can be called not only war, but lawful self-defense, for we must distinguish between wars that someone begins because that is what he wants to do and does before anyone else attacks him, and those wars that are provoked when an attack is made by someone else. The first kind can be called wars of desire; the second, wars of necessity. The first kind are of the devil; God does not give good fortune to the man who wages that kind of war. The second kind are human disasters; God help in them!

Our conclusion on this point, then, is that war against equals should be waged only when it is forced upon us and then it should be fought in the fear of God. Such a war is forced upon us when an enemy or neighbor attacks and starts the war, and refuses to cooperate in settling the matter according to law or through arbitration and common agreement, or when one overlooks and puts up with the enemy's evil words and tricks, but he still insists on having his own way. I am assuming throughout that I am preaching to those who want to do what is right in God's sight. Those who will neither offer nor consent to do what is right do not concern me. Fearing God means that we do not rely on the justness of our cause, but that we are careful, diligent, and cautious, even in the very smallest details, in so small a thing as a whistle.

On this Memorial Day, let us honor and remember those who served, even those who died in wars we may regret undertaking.

Roadside stand near Birmingham, Alabama (LOC)

This beautiful image is from the Library of Congress' Walker Evans collection at Flickr. Taken in 1936.

It is interesting that one could apparently make a living selling fish caught from rivers. Just one potential setting to remember for my time machine, when I get one.

Thursday, May 21, 2009

Outrageous quote of the day

"Humanitarianism is the expression of stupidity and cowardice."
Adolf Hitler: Mein Kampf.
I just saw this quote at the blog of Rev. Matthew Harrison, Executive Director of LC-MS World Relief and Human Care. (He of course was painting it as an ugly thought.)

I guess this is the exact opposite of my worldview, and how convenient for it to be expressed by Hitler. I would say that courage is being humanitarian even when it seems to go against your interests-- your long-term interests are almost always served by being humanitarian when mocked by those who wear their courage on their sleeve. Hitler's view here is exactly what is wrong with "conservative" nationalism.

The other day, I was listening to a story featured on NPR Story of the Day podcast. It featured an interview with- more a lengthy editorial by-- a psychologist who had been involved first in training U.S. military personnel to resist torture. Some of these psychologists then went on to perform "enhanced interrogation" techniques. Two things particularly bothered me about the psychologist's remarks:
  • He summed up the whole interrogation program with the example of bugs. If you know someone is afraid of bugs, lock him up with a bug. That doesn't sound so bad does it? The problem is that this one tactic is probably the least offensive of the techniques used, which ranged from breaking bones to sexual humiliation to waterboarding. To poo-poo concerns about the whole program by bringing up one of the least offensive measures is an exercise in propaganda. I find it interesting that Tony Blankley, in a recent Left, Right and Center program, also engaged in similar mocking of the concerns about torture as being about "putting a bug on someone's shoulder."

  • The psychologist said, "I was not there to be concerned about the mental health needs of javascript:void(0)terrorists. I was there to gather information to protect the country I love." [quote from my memory]. I wonder how many other people find that the problem with this psychologist's remarks is that they sound too much like Hitler's view of humanitarianism.

ADDENDUM: The American Psychological Association has a statement against torture. The statment lists many proscribed acts in this statement against torture, which of course includes "exploitation of fears". If the Association has a "zero tolerance" of these acts, I wonder if there are any penalties for going on the radio to defend passionately placing a bug on someone's shoulder? Given the above, I'm also convinced that the reporter in no way did her homework. I found that statement in 15 seconds of googling.

Wednesday, May 20, 2009

Excellent album for driving in car on sunny afternoon

This album by Jamendo's Professor Kliq is Creative Commons licensed. If you use it in derivative works or distribute it, you merely have to give credit to the artist and provide the same license to the subsequent works. You may of course download for personal use as well.


Tuesday, May 19, 2009

Who will remain standing in day of Judgment?

I originally sat down at my computer to vent with outrage at how the Religious Right was misusing Scripture to rationalize the aims of the Right in certain geopolitical military exploits. I had just read the dailykos article, Outrage Over the Publication of Rumsfeld's Christian War, which discusses this GQ article. Apparently someone has found some material where former US Defense Secretary had prepared scripture quotes to pep up the morale of troops fighting in Iraq. One of the passages was Isaiah 5:28:
28 Their arrows are sharp,
all their bows are strung;
their horses' hoofs seem like flint,
their chariot wheels like a whirlwind.
I wanted to learn more about the passage, because out of context I wasn't sure whether it were in fact a passage describing bad people or the actions of God's agents. Wouldn't it be like the Religious Right, I presumed, to misuse a passage by describing America's troops with biblical language meant to describe God's enemies? Anyway, while googling up the passage, I ran across the Skeptic's Annotated Bible. They had this to say in their commentary on Isaiah 5:28.
God will kill those who despise his word and fail to follow his laws. Their carcasses will be "torn in the midst of the streets."
This actually bothered me more than Rumsfeld. The writers of this commentary were trying to point out how stupid and mean and silly it was to follow a text where it is said that God will slay those who do not follow his laws. I believe this is based on a (very flawed) view of God's law as (what Luther described as) "nominal and childish sins." In this view, the laws are all about spoiling our fun, completing boring ceremonies, following the secret handshakes of the club: the law has nothing to do with man's inhumanity to man.

C.S. Lewis, on the other hand, in Mere Christianity once summarized the reasons for God's wrath as "greed and trickery and exploitation." What if God's law had the smallest iota of relevance to greed and trickery and exploitation? Why, there might be at least some kind of justice to the idea of an angry God, if He were also mad at those A.I.G.? What about all those other people who exploit the poor? What about you! What about me?! Indeed, according to Luther's Explanation to the Ten Commandments:
The Seventh Commandment.

Thou shalt not steal.

After your person and spouse temporal property comes next. That also God wishes to have protected, and He has commanded that no one shall subtract from, or curtail, his neighbor's possessions. For to steal is nothing else than to get possession of another's property wrongfully, which briefly comprehends all kinds of advantage in all sorts of trade to the disadvantage of our neighbor. Now, this is indeed quite a wide-spread and common vice, but so little regarded and observed that it exceeds all measure, so that if all who are thieves, and yet do not wish to be called such, were to be hanged on gallows the world would soon be devastated and there would be a lack both of executioners and gallows.
Who could remain standing? That is the proper understanding of God's law and wrath. It is not a reason for mocking the idea of accountability to a higher power; it is surely NOT a reason to go punching those who have committed slightly fewer sins than yourself.

Too often I feel that fundies & atheists agree on more than they disagree. Maybe the Religious Right and the less-well-read "skeptics" of Christianity would agree that sin is merely a list of a few nominal and childish vices. In that view, for God to have "wrath" over it is is both mean and stupid. But if however His law were more about lifting up the sheet and showing all the bloody ways we've exploited, harmed, and killed each other, then perhaps God's law is a reason to shudder. And seek the shelter that can only be provided by the cross.

Monday, May 18, 2009

Procedurally generated landscape -- land and sea

Here's yet another procedurally generated landscape. It shows some densely packed islands by the sea that starts out in complete chaos, but eventually establishes a more stable form, but never stops "bubbling".

This is also one of the first times I've tried's embeddable player.

Sunday, May 17, 2009

Electrons on parade

I originally found this post at It's a cool video explaining electronics from the 1950's.

Saturday, May 16, 2009

Martin Luther's "Concerning Councils"

"My friends, the Antinomians preach exceedingly well-- and I cannot but believe that they do so with great earnestness-- concerning the mercy of Christ, forgiveness of sin, and other contents of the article of redemption. But they flee from this inference as from the devil, that they must tell people about the Third Article, of sanctification, that is, of the new life in Christ. For they hold that we must not terrify people and make them sorrowful, but must always preach to them the comfort of grace of Christ and the forgiveness of sin. They tell us to avoid, for God's sake, such statements as these: 'Listen you want to be a Christian while you are an adulterer, a fornicator, a swill-belly, full of pride, avarice, usurious practices, envy, revenge, malice, etc., and mean to continue in these sins?' On the contrary, they tell us that this is the proper way to speak: 'Listen, you are an adulterer, fornicator, miser, or addicted to some other sin. Now if you will only believe, you are saved and need not dread the Law, for Christ has fulfilled all.' Tell me, prithee, does not this amount to conceding the premise and denying the conclusion? Verily, it amounts to this, that Christ is taken away and made worthless in the same breath with which He is most highly extolled."

--Martin Luther, Concerning Councils, as quoted in Walther's Law and Gospel.

Everyone's got something they are Antinomian about.

If you'll notice above, I have highlighted and colored various sins in the above lists that caught my eye. Christianity seems to be divided into camps where one is against the red sins: adultery, fornication, chemical revelry, on one hand and the blue sins: miserliness, avarice, usurious practices on the other. It's hard to find someone whose witness to Christ has a balanced approach to all of these sins. On one hand, I've met some conservatives on the internet or listened to sermons of LC-MS pastors who seem to have a wonderful grasp of confessional Lutheran doctrine when the sins are red ones. But mention the blue items as something for which we are all worthy of reproof, and they start calling you a heterodox liberal-Protestant, say that you will "offend the Christ in them," etc.. On the other hand, I've seen some other Christians engage in a tireless campaign against the violations of human decency found in those blue sins. But they seem to bend over backwards to find any basis for their campaign as long as the source is something other than confessional Lutheranism and the sin-death-cross-repentance story in scripture.

I call this controversy in Christianity the Humanitarian Question.

Friday, May 15, 2009

How to make one-pass 3D anaglyphs in povray

This requires the Megapov patch of povray

1. Give all your objects a pigment which is of the form rgb < n , n , n > , where n is between zero and one. In other words, black and white.
2. Make up two camera_view pigment patterns in povray, which are identical in every respect, including the look_at vector, except that the locations of the camera are separated by a few pov-units.
3. Make up three subsequent pigments:
i) one that makes use of your left pigment and goes from black to 3*red
pigment{function{left_camera_pigment (x,y,z).red} colour_map {[0 rgb 0][1 rgb <3,0,0>]}}
ii) one that makes use of your right pigment and goes from black to 3*green
iii) one that makes use of your right pigment and goes from black to 3*blue.
4. Set up an average pigment which combines the three with equal strength.
5. Set up a box that fills the camera (see my earlier povray posts) and has the pigment in #4 as its texture.

Now, when you render, you will be automatically creating red-cyan 3D anaglyphs in povray.


Thursday, May 14, 2009

Fundies & secularists agree on one thing.

A recent episode of "This American Life" featured an interview with a southern judge. The judge had come up with a creative sentencing program for shoplifters. He sentenced them to carry a sign in front of the store saying that they had shoplifted. For the record, I'm neutral or slightly in favor of this sentencing program. I think the program was a well-balanced piece, and was ultimately sympathetic to the judge. But one part of the segment stuck in my craw.

The interviewer thought the sentencing program were a bit extreme and uncompassionate. The interviewer asked if it weren't a bit "biblical", and the judge agreed. What bothered me was that both the (apparent) nonbeliever and the (apparent) fundamentalist agreed on a definition of "biblical" that tied it to a brutish way of dealing with your neighbor.

This is another version of the Humanitarian Question. Nonbelievers use the brutality of Christianity as a reason not to believe. Fundamentalists use the brutality of Christianity as a reason to be brutal. I say let me off of both of these buses, because they are both wrong.

Wednesday, May 13, 2009

Anselm! Anselm!

I remember being in discussion with some folks a few years ago whose views I thought were a bit towards the Liberal-Protestant side of the spectrum. (BTW, there ain't nothing wrong with being either a liberal or a Protestant, but being a liberal-Prostestant. Liberal-Protestantism can be defined as "Scholars who incline strongly to a non-dogmatic reconstruction of the Christian faith, usually concentrating on its ethical and humanitarian aspects.")

Anyway, they had a really strong beef with Saint Anselm's view of the atonement. I never really understood what it was about.

I just ran across An open letter to the Bishop-elect of Northern Michigan, by a self-described scholar of Medieval Christianity. The article makes rebuts none other than the Bishop-elect of Northern Michigan, Kevin G. Thew Forrester. Forrester had written a piece called Approaching the Heart of Faith, where he quotes someone who said that Anselm's theory of the Atonement gave support to the Crusades.

The Open Letter makes a very good case for how Anselm's theory of the Atonement is in no way to blame. If there is a focus on the shedding of blood, it's explicitly at the same time, a focus on the one-time sufficiency of Christ's sacrifice. It does not call us to go and shed the blood of whomever is unlovely around us. If someone is going to be a fool and a cretin, they'll find a way to do it, with or without the backing of the traditional doctrines of the church.

Once again, I believe that what we are faced with is another version of the Humanitarian Question. Do we have to choose between theological orthodoxy and compassion? Do we have to give up an iota of Pauline or Johannine scriptural doctrine, of the writings of Augustine or the Book of Concord, lest we become some kind of uncaring brute? Does all talk of social injustices have to be seen as a distraction from the business of the church? I say there is no need to turn our backs on either Truth or Love.

Tuesday, May 12, 2009

Inside joke for povray enthusiasts

threed14de07, originally uploaded by pterandon.

This red-cyan anaglyph was made in povray. It makes a little inside joke for those familiar with how blobs work. All four characters are essentially the same "blob" construction, they vary only in the threshold. So when I put the same negative strength cylinder cutting them like a bullet hole, it has much more effect on the skinny one, the one with the higher threshold.

I guess some jokes are made even worse by explaining them.

Sunday, May 10, 2009

Voodoo scientists attack all religion.

The April 2009 podcast of IEEE Spectrum Radio featured a segment entitled, "Superstition: Belief in the Age of Science". It featured a lengthy interview with Robert L. Park, a writer that was bothered by the harm that superstitious belief places on society. The problem was that in an attempt to debunk bad science, IEEE devoted itself to an unscientific, philosophical rant against all belief.

Among Park's repeated complaints was that "90% believe." He was bothered that 90% of Americans express belief in some kind of God. He said that this was "disproven", but the main evidence was in reference to creation. Surely, most of what "Young Earth Creationism" is about can easily be disproven. Yet there are at least three ways that Christians approach the concept of "God created the heavens and the earth." One is the stereotypical Young Earth Creationism. But there are other varieties. Some folks believe in a Young Earth but one with Appearance of Age. Others are Old Earth Creationists. Still others, like John Paull II, could be described as Theistic Evolutionists. So many flavors, so many nuances. Have all of these been disproven? Some are actually un-disprov-able! Failure to fully investigate the sociological nuances of his subject makes this piece by Spectrum Radio merely bad philosophy.

He did make a reference to prayer. I think he was critiquing a Gospel of Prosperity moreso than the traditional view of Christianity. This underscores my hunch that to many nontheists, the gospel of prosperity, theology of glory is held the correct view of Christian faith and the bible. Rubbish.

He decried the necessity to "compartmentalize" one's belief, between science and religion. I'm wondering if scientists themselves ever do this. Isn't it said that quantum mechanics and gravity are incompatible? How about particle and wave nature of photon & electron? Scientists have to compartmentalize beliefs all the time. I don't insist that the wave nature of photons explains every phenomenon that I run across.

Hey IEEE, why don't you provide some balance here? You made a philosophical rant with little science followed by an altar call to nontheism. How about you invite an Old Earth Creationist to give a little rant (with some scientific tidbits added) and follow up with an altar call to a personal relationship with Jesus Christ?

Saturday, May 09, 2009 ad on party affiliation

I don't have much to say about this poll. I just thought it was cool that I have a blog where I can make use of embed tags!

Baby sea turtles victimized by plastic debris.

Let's be careful out there with plastic litter.
Found these at the The Sea Turtle Restoration Project

Friday, May 08, 2009

procedurally generated cities

Here are some instructions on how to make a procedurally generated city in povray.

1) There are mathematical functions which vary between 0 at 1 in space.   They are smooth, in that any two points close together are likely to be similar, but random, in that any two points far apart are unlikely to be similar.  Here is a black and white representation of one such "noise function".  There are millions of ways to make the noise-- you can have ones where the gradations are steeper or more jagged or more linear or whatever.

2) One can take this noise function into some 3D programs (here, povray) and view the isosurface-- where every point of dark and light responds to some degree of elevation:

3) One can even "terrace" the isosurface.  I set up a step function here were every value below a certain threshold is a constant value, whereas the surface varies proportionally to the value above that limit.

4) And then texture it to make it look like a landscape. 
I made the flat area like a sea, gave the "shorelines" a sandy texture, and put green mountains at the highest values.

5) Why not make some cities! Take the same isofunction and terrace it a bit differently:

6) Then texture it like a city, with pools, stone terraces, blue windows, and rooftop gardens. This is what I think is quite cool.
It is an interesting exercise, in that it allows one to design a living space that completely conforms to the geometry of the landscape without knowing the landscape beforehand.   Couldn't you imagine some loony millionaires or students at progressive college campus wanting to live like this?


Thursday, May 07, 2009

Fox News lying through cropping.


3D Anaglyphs in povray, the way they're supposed to look!

What is a blog but a serial diary of your progress towards a goal? ;-)

3d4 from pterandon on Vimeo.

I had been wondering why the blue component of my attempts at anaglyphs in povray never looked right. I did some more reading on anaglyphs and saw that they are often red-CYAN, not red-BLUE. So with a little programming tweaking, I was able to set it up to be a red-cyan anaglyph. And I think they look great!

Once again, for the best effect, follow through the link to Vimeo to see it full screen.

Wednesday, May 06, 2009

Improved red-blue 3d anaglyph, one-pass rendering in povray

3d3 from pterandon on Vimeo.

Here is an improved version of the output from my algorithm for making anaglyphs in povray. It is done as a one-pass render, no post-processing required.

[Edit: Note that this still from the timeframe in which I was making red-blue anaglyphs instead of red-cyan. I'm leaving this in the historical record, because perhaps some day someone will want to know what a red-blue anaglyph looks like! ]

Tuesday, May 05, 2009

Early, faulty versions of a one-pass 3D anaglyphs in povray

Here's my psuedocode for how one can make 3D anaglyphs in povray. Get your red/green glasses and go to the Vimeo site to see it fullscreen! As is the case for most great coding efforts in povray, I couldn't have done it without a pointer from Mike Williams. It requires the Megapov patch of povray.

[Edit: I now realize that these have a mistake in how they are generated. These next few postings are literally red-blue anaglyphs, but most folks have red-cyan glasses. Check later entries of the blog for further improvements.]

3d2 from pterandon on Vimeo.

Monday, May 04, 2009

1 Mei demonstratie in Amsterdam / Demonstration on the first of May held in Amsterdam

1 Mei demonstratie in Amsterdam / Demonstration on the first of May held in Amsterdam
Originally uploaded by Nationaal Archief.

Here's a photo that showed up in the rotation on the Flickr Commons front page. It appears to be a march of some sort of Danish Communist Party. A bunch of comfortable-looking, long-haired youth are marching with hammer and sickle flags.

This photo struck me as being especially tragic. Not that I have sympathy for the communists, but because no one does. Most people would think it an evil thing to have participated in a commie rally in the 1970's. I think that even those with an extremely large, bleeding heart would find it something stupid. My ultimate reaction when seeing this was, "Why couldn't they have expended effort on something that could have lasted?"

Suppose they had a conviction that the poor masses of the earth were mistreated. Perhaps if instead they had spent their youth working in the church for John-Newton-style conversions, doing direct charity, educating workers, or even organizing nonviolent admonition of oppressors-- then history might look back on you and smile. Even if you got the same group among your elder contemporaries upset. But expend your efforts on an extreme political party, and history's reaction will range from hatred to extreme pity.