Stylized modeling and animation is hard. Because stylized renders often have simplified forms and materials, your image has to stand on the merit of concept, design, and execution rather than intricate, technical detail.
Studios like Pixar and Dreamworks deliberately aim for a style where design, proportion, and textures are simplified or exaggerated, but other facets of the production (like shaders and lighting) are true to life. This yields an aesthetic that, design-wise, is unique and interesting, but which also appears to be very realistic and lifelike. The style is referred to as cartoon (or stylized) realism.
Here are five tips to help you make CG the Pixar way:
1. Silhouette is Everything
Silhouette is one of the most critical aspects of character design, and it's impact is even more important in stylized modeling where forms often simplified or exaggerated.
Silhouette is important because it's the first shape on a character that the eye is able to distinguish. The human visual system can read and understand a character's silhouette almost instantaneously (less than three frames, or .12 seconds).
It's common knowledge that first impressions are critical, and an audience's first impression of a character is it's silhouette. If the silhouette is boring or unreadable, the audience will be disinterested. If the silhouette is unique, clear, and dynamic, the overall impression will be much stronger.
It's a good idea during the process of character creation to occasionally put a flat shade of white on your character and switch the background to black. This will give you an idea as to whether your image is succeeding at the most basic level—silhouette.
2. Hard Against Soft
One of the most common techniques in good cartoon modeling is to play hard edges against soft, organic ones.
Hard edges tend to establish easily readable planes, help the model catch light, and sharpen up the silhouette. Soft edges give the illusion of a receding form, and help establish soft gradients of color on the surface of your model.
Too much of either is jarring. You don't want your character to be 100% sharp and angular, but a character that's all soft won't read well on screen. Find the perfect mix and you'll have a home run!
3. Really Play With Proportions
With stylized modeling you want your characters and environments to be grounded in reality, but you also have a prime opportunity to really play around with proportion.
Artists have used exaggeration to convey character for as long as cartoons have existed, and adding traits like an enormous nose, a super angular jaw, absurdly thin legs, or a hulking upper body can all help convey your character's unique personality.
Look to your favorite animated characters for reference on proportion. One of the most common things you'll see in computer animation (and cartooning in general) is that characters are often 6 heads tall (instead of 7 or 8 heads for more realistic images).
4. Be Mindful of Color Saturation
When it comes time to start setting up your lights and surfacing, try pushing the saturation in your textures and materials. Obviously, really vivid color isn't going to pair well with all subject matter, but it is a look that's become fairly standard in cartoon animation.
Saturation can also be used to convey mood. Bright vivid colors are great for light and humorous subject matter, while desaturated hues convey a different mood entirely. There are some great examples of this in The Incredibles—when the film flashes back to the "golden years," the lighting TDs used bright saturated colors. When Mr. Incredible was in his drab cubicle, Pixar tuned the saturation way down.
5. Use Detail Selectively
Try not to overload your character with detail.
Remember, with stylized modeling you want your image to stand on the shoulders of concept, personality, and silhouette. When you're detailing, try playing around with using patches of selective detail instead of bringing the entire surface of the model to the same level of polish. The images in this thread are a good illustration of the concept of selective detail.
In stylized realism, most of your stylization should come from your modeling and character design. You still want to use realistic simulations for everything else. So when it comes time to figure out your lighting solution, don't be afraid to dive into global illumination, ambient occlusion, HDR lighting—whatever gives you the best results.
