Defining 3-D Computer Graphics
3- D computer graphics is a field of computer science dealing with displaying 3-dimensional objects in a two dimension space for example on a screen. They utilize a three- dimension representation using geometry which is typically stored in digital computer read only.
Real life objects are entered into the computer and converted to 3-D graphics using special software. Almost the same algorithms like that of 2-D are used to make the 3-D graphics except for some few added features.
History
The creation of computer graphics as one of the visualization tools has been in use by government agencies and corporate engineers for research centers since the 1950’s. Computer graphics has evolved in a relatively short amount of time.
The universities like the University of Utah, MIT, Ohio State, North Carolina, and New York Institute of Technology in the 1960’s later developed it more. In the 1970’s computer graphics expanded into the television world as motion pictures and broadcast video graphics.
Back then polygon meshes were used to represent the objects. The problem was that the pictures were flat and shaded which made for very unrealistic 3-dimension pictures. The solution to that was to create smaller polygons. Shading then presents the images where color applied uniformly to the polygons.
The Computer Image Corporation (CIC) developed advanced hardware and software systems like ANIMAC, CAESAR, and, SCANIMATE, which worked by scanning the artwork, then later manipulating it. In 1971 the microprocessor using integrated circuits assisted in the development of the graphics.
This advancement in technology led to the early rise of 3-D animation. These software systems could make it stretch, spin, fly, and squash around the screen. Companies that used this technology are Boeing and Bell Labs. In 1975, Mandelbrot described Fractal Geometry which created realistic natural phenomena like mountains, wood grain, coastlines, and others.
In the 1990s companies like Apple Computers, George Lucas Industrial Light, and Magic are always making and improving the computer graphic technology so as to give the world with a false digital reality. Films emerged like Terminator 2, Beauty and The Beast, Batman and Jurassic Park which significantly used 3-D images to bring contrast and blend with the hand-drew characters.
In 1996, ID Software released Quake which introduced 3-D graphics in gaming. The Microsoft also joined to form the computer gaming experience in a Windows environment. Currently, we have real-time radiosity, real-time Ray-tracing, hologram and Global Illumination which is also real-time. The future holds on creating physically-based realism.
In 3-D we use three coordinates which are X, Y, and Z Rendering and Algorithm. The components of computer graphics are the hardware, software and the application part of it. The hardware has the CPU, GPU, and other components. The software, on the other hand, has 2D,3D, algorithm and Z-Buffering.
Lastly, the application has games, films, and simulation., It has an added advantage than two-D has it adds depth to its property more than the position, color and brightness. It also has a 3-D surface on it which is called texture. In advanced methods, 3-D graphics has sophisticated techniques like ray tracing that applies realistic shadows to the motion pictures or objects.
The computer feeds the 3-D models by scanning and taking photographs of real world objects. The models are then formed using points called vertices. Vertices define the shape of models and thus create polygons Converting 3-D information into bit map is known as rendering.
Rendering requires a tremendous amount of processing power and memory. Therefore, a very powerful computer is needed. In the past, this was only possible in special workstations, but nowadays due to technological advancement, it can be found in personal computers.
1. Primitive
Computer graphics have building blocks in them which collectively work to produce a masterpiece. There is the first one which we call primitive. These are the basic geometrical shapes that help in computer graphics construction.
Each one of them has attributes like size, color, line, and width. Examples of the primitives are a line, circle, eclipse, arc, text, polyline, spline, and polygon.
2. Lighting Models
Comprehensively lighting models, the second building block also assists in the display of 3-D graphics.
It has positional light and directional light. Positional light is locating a light source close to the viewing area. The rays of positional light are not parallel. Directional light is the use light source located at a point of infinity. Here the light rays are parallel.
3. Color
The third part of the building blocks is the color. This building block is the most important of them all. In the color part, we have the primary and secondary colors. Color helps determine the contrast.
4. Texture Mapping
Texture mapping is the last building block. It is the same as when you are wrapping paper. Maps rendering is one of the ways of using computers which display the earth surface as if it was the real earth surface.
There are different types of projections:
1.) Parallel projections- They are good for exact measurement. Here the parallel lines remain parallel, and angles do not preserve it.
2.) Orthographic projection- Here the direction of the projection is normal to the projection of the plane. There are three types of orthographic projection: Frontal, top and side projection
3.) Oblique Projection- It has cavalier projection and cabinet forecasts.
4.)Perspective Projection- The distance from the center of projection to project plane is finite, and size varies with the distance. There are three perspective projections: One point, Two points, and Three point perspective.
5.) Translation- In translation the Z coordinates are transferred along the X and Y coordinates.
3-D computer graphics is in the medical field, architectural, biological, meteorological, filming industry, and many others.
The use in the medical field is in radiography field like U-T scanning, X-Rays, and others.
In architecture, 3-D graphics are used to draw the blueprint of the building and show details how the building looks upon completion.
In meteorology, it can be used to model changes in the atmosphere and expected weather patterns.
Lastly in filming computer graphics can be used to make animations, 3-D films and even in sports to add glamor to the live images.
The 3-D computer graphics continues to advance as time passes. The future looks bright for 3-D animation, in sporting, Virtual Reality (VR), communication especially the video calls and even the advanced hologram.