The 10 Principles of Photoreal 3D:

1. Clutter & Chaos
2. Personality & Expectations
3. Believability
4. Surface Texture
5. Specularity
6. Dirt, Dust and Rust
7. Flaws, Scratches and Dings
8. Beveled Edges
9. Object Material Depth
10. Radiosity

There you have it. Ten simple principles to use as guidelines in your photoreal 3D endeavors. What are they all about? I was hoping you would ask. This article will outline the first three principles so you have a basic understanding of their application. In the coming articles we'll cover the remaining 7 principles.

Let's take a moment to examine the first three principles by seeing how they were applied to the image in Figure 1.1. Before we get started with the principles, it's important to understand the background behind the image. This helps you to understand how and why the Principles of Photoreal 3D were applied to the image.

'Dwellers' is a 3D animated feature film currently in production at Komodo Studio, a 3D studio in Southern California. It's about a race of cognitive thinking robotic creatures that were created by an old toy maker named Papagaio. Papagaio created the first Dweller, Gizmo, in his basement workshop.

 

Figure 1.1 Photorealism applied!

Figure 1.1 shows Gizmo on Papagaio's workbench where he was created. The scene takes place at around 1am in the basement of Papagaio's house. He doesn't want anyone to find out about the Dwellers so he only uses a shoplight to illuminate the workbench. He's just finished adding the circuit board, which is Gizmo's brain. The scene has captured the moment at which Gizmo comes to life.

Now that you have a basic understanding of the story behind the scene, let's take a look at those Principles of Photoreal 3D and see how they were applied to the 'Dwellers' image.

PRINCIPLE 1: CLUTTER & CHAOS

Clutter is one of the most obvious traits of reality. The common problem in most 3D rendered scenes is the lack of clutter -- they're too sterile. Everything is neatly arranged. I don't know about your world but the world I live in is in complete chaos. Look around your home or office. What do you see? Well, if it's anything like my studio you see stacks of reference books, piles of papers, floppies, zips and an assortment of knick-knacks. Basically, pure CHAOS.

Reality is pure chaos. Chaos doesn't mean that everything is completely disorganized. There is actually order in chaos. Chaos means that everything in the scene cannot be aligned perfectly. You can create order by putting all the chess pieces on the board but chaos dictates that they will be rotated at slightly different angles and none of them will be in the middle of their space. There is no uniformity in reality yet, for some reason, 3D rendered scenes defy reality by neatly arranging everything. Actually, the reason is simple. 3D programs present us with countless tools for engineering our creations. Because we are submerged in this engineering environment we feel compelled to be linear in our thinking. It's far too easy to get caught up in the rigidity of 3D engineering. You need to break loose of the engineering binds of 3D and experience the creative side. Try to make it a habit to place things out of alignment in your scenes. Not dramatically out of alignment, because that would be too much chaos, but a little out of alignment. You'll see it makes a big difference in the photorealism of the scene.

Now let's see how the Clutter & Chaos Principle was applied to the workbench scene. Take another look at Figure 1.1. You'll notice an abundance of clutter. This is a workbench, and I haven't seen a workbench that is neatly arranged...particularly when it's in use. There are nuts, bolts and screws scattered everywhere. And yet, there is still an element of order in the tools that are neatly stored on the wall rack. You can't go wrong by combining chaos and order. Notice the subtle chaos in the scene. One of the two batteries has fallen over. The camera box is turned away from the wall slightly. The needle nose pliers are open and the red wire isn't coiled perfectly. Probably the best use of chaos is the hot soldering iron that is burning the workbench. I don't recommend doing this in your workshop, but I don't recall the last time I saw anyone use a heat sink with a soldering iron... that would be too much of a hassle for the busy craftsman.

Speaking of the craftsman, it's very important to understand the personality of the characters involved in your scene. This takes us to the next Principle of Photoreal 3D: Personality & Expectations.

PRINCIPLE 2: PERSONALITY & EXPECTATIONS

Expectation is a large part of Photorealism. When exploring the personality of your scene's creators, it's important to consider the viewer's expectation. We have come to stereotype nearly everyone and everything. While stereotypes may not always be flattering, they do provide you with perfect guidelines for developing your photoreal scenes. Stereotypes don't limit your creativity, instead they provide you with simple guidelines for ensuring your work will be recognized as photoreal.

For example, we assume that intelligent people are neat. And, of course, that less intelligent people are sloppy. While this may be true in some cases it certainly doesn't apply to everyone. Still, when developing a scene created by an intelligent character you should aim for neatness to make the scene believable to the viewers. Another example would be how the intelligent character looks. What would happen if you made a scientist a buff, handsome hunk? The answers is simple, nobody would believe he was smart. Hollywood has conditioned us to believe scientists are skinny, nerdy looking guys with glasses and pocket protectors. We've also been programmed to believe that muscle bound macho men are dumb as dirt. You can't escape the stereotypes and expect the scene to be credibly photoreal. Even though it may be completely realistic looking there will still be some doubt in the viewers mind due to their expectations. It would be like fighting a millions years of evolution. Everyone has been stereotyped... even 3D artists.

Let's see if we can extract Papagaio's personality from the workbench scene. Take a look at Figure 1.1. Immediately you can see that he has a neat side to his personality since there are tools carefully hung on the wall rack. This tells you that he respects his tools and workspace. You'll see some aging on the tools but they are still in great condition. The workbench surface is dirty but it doesn't have a lot of damage like paint stains and gouges. Even the wire is coiled up neatly as opposed to being knotted. These are all subtle expressions of his personality. We have to assume that Papagaio is rather intelligent since he has created an artificial life form capable of cognitive thought. Therefore, by stereotype definition, he is neat. But because he is an inventor, a messy stereotype, his workspace is cluttered while he is working. He probably cleans it up after he's done. We can also assume, since he is an inventor, that he will have reference books piled on his workbench. This justifies the book in the scene.

You can see how the scene is starting to make a great deal of sense based on the personality of Papagaio. It's very important to get inside the head of the characters responsible for the development, and maintenance, of the scene you are creating. It's also a lot of fun.

Working with the Viewer's Expectations. It is also important to get inside the heads of your viewers to understand their expectation of the scene. We have come to expect certain attributes of particular scenes and environments. For instance: we expect an industrial factory to be dark and dirty; a movie theater to be littered with popcorn and empty cups; space ships to be covered in grease stains; monsters to be very ugly with huge fangs and dinosaurs to be earth tone colors -- you get the idea.

We have been conditioned by our experiences to make assumptions about the nature of things. Media has played a major role in defining our expectations. When was the last time you saw a spotless factory in the media? Probably never, but there are actually many factories that are extremely clean. Yet, if I were to show you a spotless factory scene you would say it didn't look realistic because there wasn't any dirt. How can a factory operate without making a mess? We can't accept a spotless factory, because the media has taught us that it isn't possible for a factory to be clean.

Here's a great example of the expectations we create ourselves: If I showed you a render of a dinosaur with bright colors you would say it was artificial, in spite of the fact that dinosaurs were most likely very colorful. Because of their size and skin texture, we tend to compare dinosaurs to current day behemoths like elephants. But these are also pachyderms - pachyderms don't have colorful skin. These skin colors wouldn't make sense for a dinosaur since they were reptilian and reptiles are very colorful, particularly the males. They were depicted with subtle tones by the media because we wouldn't expect them to be colorful.

This is brings up an important point. You need to conform to people's expectations in spite of the fact that they may be occasionally misguided. It's all part of making the scene believable - which just happens to be the next Principle of Photoreal 3D.

PRINCIPLE 3: BELIEVABILITY

There are 2 types of believability: models and surfaces. You don't need to have both to make an object believable. For example, a futuristic space ship isn't a real object but if the surfaces are something we expect, the object becomes believable. The opposite also applies. If you had a photoreal model of a computer screen that was painted with psychedelic colors it would still seem believable, in spite of the strange colors, because a computer monitor is a familiar object. It would be a bizarre choice of coloration but the computer just might belong to a Grateful Dead fanatic.

Another good example of believable surfaces would be the dinosaur we discussed earlier. A colorful dinosaur wouldn't be believable even if the model was physiologically perfect. We just don't accept the colors. On the other hand, an earthtone dinosaur with flaws in the physical design would be believable. There are only a few cases where we have preconceived notions for the physical structure of a dinosaur. The T-Rex is a perfect example of a dinosaur's physical structure that we have come to expect. The media has told us that the T-Rex has tiny arms. Any deviation from that structure and the creature becomes less believable. We wouldn't buy into a T-Rex with large upper arms, even if the surfacing is something we expect.

Let's take another look at Figure 1.1. What makes this scene believable? Actually there are many things. First and foremost, the scene is comprised of all real-world objects. Most of the objects in the scene are recognizable to everyone, particularly the tools. They lay a solid foundation for believability. The book is another element of believability. It adds credibility because it is easily recognized as a real-world object. All of these items add a great deal of believability to the scene but the batteries really bring it home. Take a look at the batteries in Figure 1.2. They are the most recognizable objects in the scene. This helps build photorealistic credibility for the entire scene. Key photoreal objects, like the batteries, are referred to as Object Anchors.

Using Photoreal Object Anchors to Make Your Scenes Believable. One of the best ways to ensure viewers perceive your scene as photorealistic is to use Object Anchors. An Object Anchor is a recognizable object that has undeniable photorealistic attributes. More often than not, it's a simple object. Usually one that is surfaced with real-world texture maps.. These are the easiest objects to make photoreal. It can be as simple as a product box with scanned textures or maybe a book with a commonly seen cover.

 

Figure 1.2 Believable objects are a necessary element.

It's important to make the distinction between objects that are recognizably photoreal and those that appear realistic.

For example, a chair is not an Object Anchor because it isn't immediately recognizable. We know that it's a chair, but we probably haven't seen the specific chair that's in the scene. While it may be realistic, it isn't recognizably photoreal. Objects like furniture are not good Object Anchors because their styles are too varied. An effective Object Anchor needs to have detailed familiarity. It needs to be a very specific object that we frequently see in our daily lives. A box of cereal is an excellent object anchor, particularly if the textures were scanned from an actual box. Who hasn't seen a Wheaties box? The cereal box is a great Object Anchor because all cereal boxes are constructed the same way. It's the object's construction that makes it a solid Object Anchor.

It's important to note that the texture you apply to the Object Anchor must fall into the guidelines of what the viewer expects. This means you can't change the basic layout of a cereal box without losing its photoreal credibility. We are accustomed to seeing a specific layout for cereal boxes, for example the manufacturer's name at the top of the box, a product name underneath the manufacturer's name, a picture of the cereal under the product name, a nutritional label on one side panel and something gimmicky on the other side panel; and, of course, some kind of bonus offer on the back. If you dramatically alter this design with your textures you'll negate the object's credibility.

Another excellent Object Anchor is a battery. All batteries are basically the shaped the same. They are commonly seen items and the viewer is actually fairly flexible on the texture design. Figure 1.1 makes good use of a battery to establish believability.

To see a closer view of the batteries, take another look Figure 1.2. While the model is nice, its the textures that makes it believable. The object's surfacing matches the real-world object so well that you can't tell the difference. Adding a believable object like this gives the whole image great leverage in convincing the viewer that it's real. If the viewer believes that one object in the scene is real, they are likely to assume the whole thing is real. This can be a great benefit when creating photorealistic scenes. Object anchors are a critical part of every photoreal scene.

While the object anchor is crucial to the scene's believability, it doesn't need to be the main focus of the scene. The batteries in Figure 1.1 are a very small element in the scene. Gizmo, the robot, is the main focus of the scene. The batteries were added to anchor the photorealism of the scene, and build more credibility for the fantasy robot object. Actually, there are several anchors in this scene. The book and camera box are also powerful Object Anchors that solidify the scene's photorealism. Books and product packages are very familiar objects that make them perfect Object Anchors. This brings us to another aspect of believability: Object Familiarity.

Using Familiar Objects to Make Fantasy Objects Photorealistic. Familiar Objects play a major role in a scene's photoreal credibility. Familiar Objects are a little different that Object Anchors. Object Anchors are used as a foundation of the scene's photorealism. Familiar Objects are used to make fantasy objects appear realistic. For instance, to make a futuristic car that flies appear realistic, we add familiar components to the body such as: headlights, running lights, turn signals, bumpers, windshield wipers, rear view mirrors, etc. These are all Familiar Objects that make the fantasy object appear realistic. Gizmo, the robot, is a great example of a fantasy object that incorporates Familiar Objects.

Take a look at Figure 1.3. Even though Gizmo isn't a real world object, he is comprised of very familiar real-world parts. You can immediately identify his right arm as a Swiss Army knife, and the speaker on his back is quite familiar as well. If you take a closer look you'll recognize his feet as headphone speakers. And, of course, his body is an oilcan - it even says it on the label. All of these real-world objects help to make Gizmo believable in spite of the fact that he is completely imaginary.

You should make an effort to include Familiar Objects in the construction of all your fantasy objects. There will be cases where the fantasy object is too sophisticated or too old to incorporate Familiar Objects. In these situations you need to focus your efforts on creating believable surfaces, which we will cover in the next issue.

 

Figure 1.3 Object recognition is important.

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Part II - Principals 4 - 6
Part III - Principals 7 - 10