Advanced 3D Techniques

If you flatten a 3D object's XYZ coordinate system into a 2D image, you'll receive UVW space. UV coordinates consist of "U" that represents the horizontal axis, "V" that stands for the vertical axis, and "W" that is for the depth. "Why do I need to care about depth in 2D?" The thing is, each UVW coordinate has a corresponding point in 3D space — a vertex. In turn, the "W" coordinate ensures each vertex is displayed correctly in 3D if there's rotation, scaling, shearing, or offset.^[1]

At some point in their work, 3D artists need to cover the 3D object in texture — color or any other material properties. To do so, they use UVW coordinates that organize the process of wrapping a 2D image onto a 3D object seamlessly — UV mapping. In other words, think of unpeeling an orange, laying the peel out flat, and wrapping it back around the orange. UV mapping makes sure each point of a 2D texture image knows exactly where it should be placed and fits perfectly without stretching or pinching. 

High poly modeling implies what it says — a high amount of polygons! The 3D model can contain over 10k of polygons — a collection of vertices, edges, and faces — that define the shape. Such modeling has its pros as it helps craft more elegant and detailed objects. However, rendering such images may take hours to complete, and the editing can turn into an exhausting chore.^[2]

Low poly modeling settles for up to 2k of polygons and suits for on-the-fly rendering — a perfect match for game development. Good news — low poly models are light-weighted and easy to use and edit. But if you want to create a photorealistic image — low poly modeling won't live up to your expectations.

To maintain the balance between stunning and vivid graphics and flowing and smoothing animation, 3D artists should know the techniques of the level of detail (LOD). LOD allows us to reduce the complexity of a 3D model representation and contains practices of efficient workload usage. For instance, there's no need to see the details of the object when it moves fast or disappears in the distance. LOD decreases the number of triangles, resulting in a higher performance, as fewer triangles are easier to proceed.^[3] 

3D video games developers swear by LOD to provide a seamless experience to their users.

What differentiates a good video game from a mouth-dropping photorealistic virtual adventure? That's right, the lighting. In 2001, ambient occlusion was used in the movie Pearl Harbor and marked a turning point in video and game development. Technically speaking, ambient occlusion is a shading and rendering technique that calculates how bright certain parts of a screen should be in relation to other objects of a scene. Ambient occlusion defines areas that are fully exposed to the light source, for example, a character's face, and darkens other parts, such as creases of clothes, imitating the natural illumination.^[4]

What makes people love video games so much? Because they simulate real-life and physical behavior. But what's even more outstanding — they can outperform objects' abilities and intentionally deviate from actual physics. To represent physics simulation, 3D artists and game developers use a physics engine. This software component replicates real-world physics, including rigid-body dynamics — the movement and interaction between solid and immovable objects, and soft-body dynamics that simulate mobile bodies and fluids.^[5]