Part Four: The Rise of Personal Computers & Graphics
By Shreyas K. Rising 8th Grade
Welcome to section three. This section is a lot shorter than the previous ones, but nevertheless it’s still exciting! Keep on the lookout for more in this section. Enjoy!
Introduction:
In the past sections, we talked about how computer work but now it’s the rise of personal computers. Personal Computers are some of the most bought electronic devices in the world, and it’s pretty easy to see why. At this pointing time, you basically need a computer for everything. You need it for work, school, and obviously for reading this… maybe? Anyway, PCs are really important and so are the graphics in the PC. The graphics are vital to many people who play video games on their PC. In this section, we’ll be talking about all of that stuff. Enjoy!
Part Four: 3D Graphics
Welcome to the last part of this section. Today we’re talking about 3D graphics.
3D computer graphics, or three-dimensional computer graphics (in contrast to 2D computer graphics), are graphics that use a three-dimensional representation of geometric data (often Cartesian) that is stored in the computer for the purposes of performing calculations and rendering 2D images. The resulting images may be stored for viewing later or displayed in real-time.
3D computer graphics rely on many of the same algorithms as 2D computer vector graphics in the wire-frame model and 2D computer raster graphics in the final rendered display. In computer graphics software, 2D applications may use 3D techniques to achieve effects such as lighting, and, similarly, 3D may use some 2D rendering techniques. The objects in 3D computer graphics are often referred to as 3D models.
Unlike the rendered image, a model’s data is contained within a graphical data file. A 3D model is a mathematical representation of any three-dimensional object; a model is not technically a graphic until it is displayed. A model can be displayed visually as a two-dimensional image through a process called 3D rendering, or it can be used in non-graphical computer simulations and calculations. With 3D printing, models are rendered into an actual 3D physical representation of themselves, with some limitations as to how accurately the physical model can match the virtual model.
William Fetter was credited with coining the term computer graphics in 1961 to describe his work at Boeing. One of the first displays of computer animation was Futureworld, which included an animation of a human face and a hand that had originally appeared in the 1971 experimental short A Computer Animated Hand, created by the University of Utah students, Edwin Catmull and Fred Parke. 3D computer graphics software began appearing for home computers in the late 1970s. The earliest known example is 3D Art Graphics, a set of 3D computer graphics effects, written by Kazumasa Miyazawa and released in June 1978 for the Apple II.
3D computer graphics creation falls into three basic phases:
- 3D modeling — the process of forming a computer model of an object’s shape
- Layout and animation — the placement and movement of objects within a scene
- 3D rendering — the computer calculations that, based on light placement, surface types, and other qualities, generate the image
Modeling:
The model describes the process of forming the shape of an object. The two most common sources of 3D models are those that an artist or engineer originates on the computer with some kind of 3D modeling tool, and models scanned into a computer from real-world objects. Models can also be produced procedurally or via physical simulation. Basically, a 3D model is formed from points called vertices that define the shape and form polygons. A polygon is an area formed from at least three vertexes (a triangle). A polygon of n points is an n-gon. The overall integrity of the model and its suitability to use in animation depend on the structure of the polygons.
Layout & Animation:
Before rendering into an image, objects must be laid out in a scene. This defines spatial relationships between objects, including location and size. Animation refers to the temporal description of an object (i.e., how it moves and deforms over time. Popular methods include keyframing, inverse kinematics, and motion capture). These techniques are often used in combination. As with animation, physical simulation also specifies motion.
Rendering:
Rendering converts a model into an image either by simulating light transport to get photo-realistic images or by applying an art style as in non-photorealistic rendering. The two basic operations in realistic rendering are transport (how much light gets from one place to another) and scattering (how surfaces interact with light). This step is usually performed using 3D computer graphics software or a 3D graphics API. Altering the scene into a suitable form for rendering also involves 3D projection, which displays a three-dimensional image in two dimensions. Although 3D modeling and CAD software may perform 3D rendering as well (e.g. Autodesk 3ds Max or Blender), exclusive 3D rendering software also exists.
The next section will be out soon.