The Reality Game is folding

I will be folding this blog shortly. All non-duplicate posts here will be moved, edited and republished on my main blog, The Mad Perseid, starting next week. The reason for this reversal? I can no longer see any reason to maintain two blogs, and it is distracting trying to drive traffic to both blogs simultaneously.

So, in the interests of simplicity, I will be consolidating the two. Hopefully, I'll be able to sit down again soon and write many more additional part of this essay. In the mean time, the existing entries will be edited and republished on the main blog.

However, this blog will not be deleted; it will simply contain an entry direct visitors to the other blog. This will be done for continuity. Please stay tuned.

Reality and the world of 3D - Part 14

3D - Continued 4

I really want you to understand this difference between an analog real world and a digital computer world. Take a white piece of paper and put a pop can on it, then with a pencil draw a circle by following the curvature of the bottom of the can. When you have done that, drink the contents of the can. Now, open the Paint application that's part of every Windows install and draw a circle. Compare the circle you drew on paper with the circle on the computer screen. Do you see a difference?

Notice how smooth the circle that you drew on paper is, and how rough the circle you drew in Paint is. This is a major difference between the real world and the computer world. In the real world, a sheet of paper is a material that accepts inks of many kinds. It is a canvas with an ability to show color limited only by the size of the brush(or pen tip) and the absorbtion factor of the ink(or paint) used. It is also a material that doesn't care where you paint on it, or how large or small your strokes are, it can represent them all, including extremely detailed shapes. We can say, then, that the paper material has a virtually unlimited resolution, in other words, it functions as an analog device.

Computers, however, are not like that at all. On a computer, a painting canvas is represented by a very specific resolution that you have to choose. Resolution is defined by a cartesian grid, with an 'X' and 'Y' axis, 'X' going left-to-right, and 'Y' going up-to-down. For example, common resolutions are 640x480, 1024x768, 1280x960, 1280x1024 and 1600x1200. If these numbers sound familiar, it is because these numbers are also what your screen resolution is, and also the resolution of images coming out of digital cameras. Though these resolutions are common, they are, by no means, the only resolutions you are limited to when working with computer images.

The higher the resolution of the image, the higher the level of detail you can see on the screen and print. There are drawbacks, however. Every time you double the size of your image, say, by going from 640x480 to 1280x960, you quadruple the amount of space it takes on disk and in memory. 640*480 = 307,200 dots, but 1280x960 = 1,228,800 dots, which is four times greater than 307,200 dots. This is because you double each dimension(X and Y axis) separately. Dots are also known as 'pixels', and hence the term “megapixel”. 1280x960 is a 1 megapixel image, but 1600x1200 is a 2 megapixel image. A megapixel is approximately 1 million pixels. These terms aren't exact, as you can see, so you must do your own calculations to determine exactly the resolution of any given image.

Your image resolutions need not match your screen resolution. You can easily view a 1600x1200 image on a 1280x1024 screen because the software that displays it will either let you scroll left-right and up-down, or will simply scale the image down for display purposes. In effect, you see a smaller version of your image, but can easily zoom in and out to see more detail.

Now that you know about resolutions and pixels, we will now proceed with the discussion of how this relates to a computer screen being used as a canvas for painting. Please stay tuned...

Reality and the world of 3D - Part 13

3D - Continued 3

The Universe is infinitely diverse, and it is a diversity that is extremely difficult, if not impossible, for a computer to represent. Why? Because the Universe can be thought of as being analog, but computers are digital. This means that computers, while capable of coming close, cannot achieve the level of diversity that's easily achieved by the simplest objects in nature. Let's take a look at why.

For an example of the difference between analog and digital, let's look at something that's probably available in every home, a radio. Most people have had radios with analog tuners before, and may still have them to this day, and certainly many people now have digital tuners on their radios. Look at your analog radio. When you move the tuning dial, your radio is tuned to the exact frequency you choose, regardless of how fast or how slowly you turn the dial. You can tune to any frequency on the dial, including all of the in-between frequencies. By contrast, digital tuners can only tune in to very specific frequencies. Most digital tuners tune to odd numbers such 103.1 or 107.1. They can also tune into 103.3 or 106.9. Some can tune to both even and odd numbers, but certainly nothing in between.

Let's now look at multi-meters. These devices measure voltage, resistance and current, and come in both analog and digital models. Just like the analog radios, analog multi-meters show exact values that exist on their scales, though sometimes they make reading the exact value a bit difficult. Digital multi-meters let you easily read the value, but it may not as accurate as a well-designed analog multi-meter. This is not to imply that analog is better than digital, only that it displays its values differently and often more precisely, though whether such exactness is required is a different question.

So, basically, what we're saying is that analog shows exact numbers of almost any complexity, while digital only shows discrete numbers within a certain precision. Put another way, analog can be represented by fractions(ie., one third, or 1/3), while digital represents only discrete values(ie., 0.3333333~). In many cases, where digital can represent whole numbers of sufficient size, it is far superior to analog. This is especially true in cases where information has to be transmitted.

You may be asking yourself why we're spending so much time on differences between analog and digital. Computers are digital, so why worry about analog. Well, the reason I spend so much time dwelling on this subject is that I want you to understand how the reality of 3D computer graphics differs from the reality of the real world. Please stay tuned for more.

Reality and the world of 3D - Part 12

3D - Continued 2

In the previous sections, you learnt what reality is and what 3D computer graphics allows the artist to do and how it works. You also learnt to look at reality on an object-by-object way. Let's now put it all together and see how reality relates to 3D computer graphics.

First, let's recap a very important question. What is “3D computer graphics”? At it's simplest, “3D computer graphics” are images generated by a computer based on information provided to it in a 3-dimensional, computer-stored space. It may include life-like representations of people, animals, worlds or even simple geometric forms or objects such as spheres, pyramids and cubes. These generated images are represented on a 2-dimensional grid and uses converging lines(and other techniques) to simulate depth.

There's the key operative word: simulate. That's all “3D computer graphics” really are, simulations. And not complete simulations, either. If you make a scene taking place inside a warehouse that has no windows, there is no need to simulate the outside world. In other words, when we're creating our 3D scenes, we're only creating them only so far as the camera can see.

“Camera?” Yes. In 3D software, all the regular photographic concepts such as cameras and lights apply.

Let's change tracks for a moment, and discuss the nature of universe. We haven't done that yet, we've only discussed the objects and forces in nature itself. No, this isn't going to be one of those metaphysical Star Trek type discussions.

Dr. Crusher: “If there's nothing wrong with me, maybe there's something wrong with the Universe.”

Dr. Crusher: “Here's a question you shouldn't be able to answer. Computer, what is the nature of universe?”

Computer: “The universe is a spheroid object seven hundred meters of diameter.”

---- Star Trek TNG: Remember Me

No, what we're going to discuss is the diversity of the Universe. Please stay tuned... In fact, the Universe is infinitely diverse, and it is a diversity that is extremely difficult, if not impossible, for a computer to represent.

Reality and the world of 3D - Part 11

3D - Continued 1

When we look at the world around us, we recognize things for what they are. They are people, they are cars, they are buildings, they are airplanes, fridges, stoves, TV sets, computers, and an almost infinite number of other objects around us every day. Each we recognize by its shape, noise, smell and feel. Sometimes we may recognize something as an object type, but not an exact object name. For example, many of us would recognize a machine, but we may not known what kind of machine it is.

So, as people, we rely on our varied senses, as well as memory, deduction and reasoning, to determine the function of the forms around us. Even animals do it, to a degree. You cannot expect a dog to understand what a computer it is, but it certainly can tell its own sleeping place from the other dogs'. This is where “reality carries its own conviction” comes in.

Objects on a photograph look real because they are real. When a light shines on a pane of glass, it affects the way it looks, it adds reflection and refraction, depending on the type of glass and the light. When you see a car sitting on the ground, you see the part of the tire touching the ground deformed as the weight of the vehicle rests on it. After a rain shower, most things are wet, and quite a few of them are reflective, but not entirely. Roads are uneven, as are the rain puddles on them.

What all this means is that in the real world, the world of photography, each object behaves according to its design, automatically, and with very little interference from you. Things in the real world simple are, you do not need to fake them. Now, it is true, that photography can also be misdirection and special effects, but that isn't what the real world is generally all about.

In the next section, we will begin our discussion on how it all relates to 3D computer graphics. Please stay tuned.

Reality and the world of 3D - Part 10

3D

OK, so we can describe a car and what it can do. So what? you ask. Well, that's the first step to understanding 3D computer graphics. Let's talk about that now.

What is 3D computer graphics? At its simplest, 3D computer graphics allows the artist to configure a scene with various elements such as sky, atmosphere, light, terrain, water, plants, people, animals, simple and complex objects, and other such entities. While in the process of setting up the scene, the artist can view the scene from any angle in the three dimensions. Once the scene is configured to the artists satisfaction(or as the time allows), the artist then instructs the computer to produce an image from a particular point of view.

In many ways, it's much like photography. You position the model and all the props, set up the lights, point the camera, focus and click the shutter-release button. You then get a photograph, printed on photo paper, or displayed as an image on your screen. This is exactly what happens when you instruct the computer to produce an image from your 3D scene. The computer analyzes the objects, the lights, the textures, and all the other information contained therein, and begins calculating. In effect, it produces a 2D photo-like image from your 3D scene, just like your camera takes a real-world 3D scene in front of the lens and turns into a 2D image on film or memory card. In my opinion, if you come from a photography background, it will be easier for you to understand proper scene design in 3D than if you've never handled a camera.

There, of course, differences between 3D computer graphics and photography. For one thing, photography is instantaneous. If, for example, you have a busy scene in front of you, like a mirror market, it will take the camera no more time to record that image than it would an image of a blank wall. That is not so for 3D computer graphics. The more complex the scene, the more lights or reflections you have, the more time it takes the computer to calculate everything and produce an image. Some images are so complex, they'll literally take days for the computer to produce. That's days of calculations in addition to the amount of time it took for you setup your scene in the first place.

Another difference is that in 3D computer graphics, every element of the scene, every wall, every chair, every desk, every character, human or otherwise, must be created, either by you or by mesh designers. We'll talk about that in a later section.

In the very first section of this essay, I introduced the concept of “reality carries its own conviction.” In the next section, I will discuss it. Please stay tuned.

Reality and the world of 3D - Part 09

Reality - Continued 8

Congratulations! You are now able to describe how various objects in the world around you work, how they look, what they do, and even how they affect other objects around them. You know that objects have certain properties, such as color and transparency, and that they can do things like move in and out of other objects.

You've also learned about water, other fluids and light, and how each affects the others. Now let's talk about how it all hangs together. So far, we have looked at simple objects, such as desks. These objects can only perform very few actions. Let's now look at a more complex object, such as a car.

Ah, the car. Most of us love our cars, and I hope that love affair will never end. But have we really thought about them, in terms of form and function? Most people are content to get in their car, start the engine and drive. But let's look at the car.

A car, at its most basic, has a certain shape, it has four wheels, and it has see-through windows, or at least, if you're a pimp, it has distinct windows that may not let a lot of light through; the windshield is generally relatively transparent. The car may have a visible antenae, though many newer cars do not have those. When you see a construct made of metal, glass and rubber hurtling down the highway, you know it is a car. Through its shape, you may recognize different kinds of cars, but the fact that they are cars remains constant. The same is true of trucks; they may look different from cars and from each other, but the shape and size tells you what it is, a car or a truck.

OK, now let's look at what a car does. It has at least two doors, often four. These open and close, but only up to a certain angle. The door handles move. Side windows are mounted on doors, and move up and down; they also move with their doors, when those doors are opened or closed. Windshield and rear windows do not move. Wiper blades are attached to wiper arms and move together with the arms. The hood covering the front compartment, and the trunk covering the rear compartment, open and close by tiping up and down. Wheels spin around their centers and turn left and right, but only to certain degrees. If the car has an external antenae, it will wave and vibrate in the wind.

Now, how do you know the engine is running without raising the hood? It makes a sound generally recognizable as a running engine. When you turn the key in the ignition, it sends an electrical impulse to the starter motor which turns over the engine and it starts. If you see a car moving on the highway and you can see no one inside it, it will look very unnatural to you, unless it is sitting on a car transporter truck. If you see it moving down the highway and there's someone in it, but you don't see the wheels spin, it also will look very unnatural to you.

Think about other complex objects and try to come up with a list of actions those objects can perform and what will make it look natural or unnatural.

What is the point of this exercise, you may wonder. Stay tuned and you will find out...

Publishing has restarted

I will now continue posting new parts of the essay “Reality and the world of 3D”. Posting frequency will be every few days.

On hiatus

“The Reality Game” is currently taking a break, and will return to full-time posting on Monday, March 7^th, 2005. Please visit us again, and thank you for your continued support.