1.
3D rendering
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3D rendering is the 3D computer graphics process of automatically converting 3D wire frame models into 2D images with 3D photorealistic effects or non-photorealistic rendering on a computer. Rendering is the process of creating the actual 2D image or animation from the prepared scene. This can be compared to taking a photo or filming the scene after the setup is finished in real life, several different, and often specialized, rendering methods have been developed. These range from the distinctly non-realistic wireframe rendering through polygon-based rendering, to advanced techniques such as, scanline rendering, ray tracing. Rendering may take from fractions of a second to days for a single image/frame, in general, different methods are better suited for either photo-realistic rendering, or real-time rendering. Rendering for interactive media, such as games and simulations, is calculated and displayed in real time, in real-time rendering, the goal is to show as much information as possible as the eye can process in a fraction of a second. The primary goal is to achieve an as high as possible degree of photorealism at an acceptable minimum rendering speed, rendering software may simulate such visual effects as lens flares, depth of field or motion blur. These are attempts to simulate visual phenomena resulting from the characteristics of cameras. These effects can lend an element of realism to a scene and this is the basic method employed in games, interactive worlds and VRML. The rapid increase in processing power has allowed a progressively higher degree of realism even for real-time rendering, including techniques such as HDR rendering. Real-time rendering is often polygonal and aided by the computers GPU, animations for non-interactive media, such as feature films and video, are rendered much more slowly. Non-real time rendering enables the leveraging of limited processing power in order to obtain higher image quality, rendering times for individual frames may vary from a few seconds to several days for complex scenes. Rendered frames are stored on a hard disk then can be transferred to media such as motion picture film or optical disk. These frames are then displayed sequentially at high rates, typically 24,25, or 30 frames per second. When the goal is photo-realism, techniques such as ray tracing or radiosity are employed and this is the basic method employed in digital media and artistic works. Techniques have been developed for the purpose of simulating other naturally occurring effects, examples of such techniques include particle systems, volumetric sampling, caustics, and subsurface scattering. The rendering process is expensive, given the complex variety of physical processes being simulated. Computer processing power has increased rapidly over the years, allowing for a higher degree of realistic rendering
2.
Web browser engine
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A web browser engine is a program that renders marked up content and formatting information. A layout engine is a component of web browsers, email clients, e-book readers. Engines may wait for all data to be received before rendering a page and this can result in pages changing as more data is received, such as images being filled in or a flash of unstyled content if rendering begins before formatting information is received. Current versions of Chromium/Chrome and Opera are based on Blink, a fork of WebKit, trident has been superseded by EdgeHTML. Opera Softwares proprietary Presto engine is licensed to a number of software vendors. MARTHA is a software engine developed with Java by RealObjects. The vendor prefix for MARTHA is -ro- The first web browsers were monolithic and they used various techniques inherited from text processing, such as regular expressions, to parse HTML into a visual representation. Later they adopted a more modular approach and were split into a host application, the engine does most of the work. It essentially takes a URL and a set of window rectangle coordinates as arguments and it then retrieves the document corresponding to the URL and paints a graphical representation of it in the given rectangle. It also handles links, forms, cookies, client-side scripting, plug-in loading, the host application provides the menu bar, address bar, status bar, bookmark manager, history and preferences functionality. It embeds the engine and serves as an interface between the user, the engine, and the operating system. Since it provides the elements surrounding the area in which the engine paints documents. This modular approach has the advantage that it becomes easy to embed web-browser engines in a variety of applications. For example, the engine used by a web browser can be used by an email client to display HTML email. On-line help systems integrated in applications have moved from using custom formats to using standard HTML displayed with a web-browser engine. The EPUB3 e-book standard uses an engine to render XHTML. Comparison of web browser engines List of layout engines Layout Code refactoring Rasterisation Page description language User agent
3.
POV-Ray
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The Persistence of Vision Ray Tracer, or POV-Ray, is a ray tracing program which generates images from a text-based scene description, and is available for a variety of computer platforms. It was originally based on DKBTrace, written by David Kirk Buck, there are also influences from the earlier Polyray raytracer contributed by its author Alexander Enzmann. POV-Ray is free and open-source software with the code available under the AGPLv3. Sometime in the 1980s, David Kirk Buck downloaded the source code for a Unix raytracer to his Amiga and he experimented with it for a while, eventually deciding to write his own raytracer, named DKBTrace after his initials. He posted it to the You Can Call Me Ray bulletin board system in Chicago, in 1987, Aaron A. Collins downloaded DKBTrace and began working on an x86-based port of it. He and David Buck collaborated to add more features. When the program proved to be more popular than anticipated, they could not keep up demand for more features. Thus, in July 1991 David turned over the project to a team of working in the GraphDev forum on CompuServe. At the same time, he felt that it was inappropriate to use his initials on a program he no longer maintained. The name STAR was considered, but eventually the name became the Persistence of Vision Ray Tracer, or POV-Ray for short, in 2002, POV-Ray became the first ray tracer to render an image in orbit, rendered by Mark Shuttleworth inside the International Space Station. Features of the application and a summary of its history are discussed in an interview in February 2008 with David Kirk Buck, POV-Ray has matured substantially since it was created. A large number of tools, textures, models, scenes and it is also a useful reference for those wanting to learn how ray tracing and related geometry and graphics algorithms work. The current official version of POV-Ray is 3.7.7 betas SMP implementation, POV-Ray internally represents objects using their mathematical definitions, all POV-Ray primitive objects can be described by mathematical functions. This is different from many 3D computer modeling packages, which typically use triangle meshes to compose all objects and this fact provides POV-Ray with several advantages and disadvantages over other rendering / modeling systems. POV-Ray primitives are more accurate than their polygonal counterparts, POV-Ray primitives are also simpler to define than most of their polygonal counterparts. In POV-Ray, a sphere is described simply by its center and radius, in a mesh-based environment, on the other hand, primitive-, script-based modeling is not always a practical method to create objects such as realistic characters or complex man-made artifacts like cars. Those objects have to be created in mesh-based modeling applications such as Wings 3D or Blender, the following is an example of the scene description language used by POV-Ray to describe a scene to render. It demonstrates the use of a colour, camera, lights, a simple box shape having a surface normal and finish
4.
Photorealism
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Photorealists use a photograph or several photographs to gather the information to create their paintings and it can be argued that the use of a camera and photographs is an acceptance of Modernism. By the time the Photorealists began producing their bodies of work the photograph had become the means of reproducing reality. Though Photorealists share some aspects of American realists, such as Edward Hopper, Photorealists were much more influenced by the work of Pop artists and were reacting against Abstract Expressionism. However, whereas the Pop artists were primarily pointing out the absurdity of much of the imagery, the association of Photorealism to Trompe Loeil is a wrongly attributed comparison, an error in observation or interpretation made by many critics of the 1970s and 1980s. Trompe Loeil paintings attempt to fool the eye and make the viewer think he is seeing an actual object, when observing a Photorealist painting, the viewer is always aware that they are looking at a painting. The word Photorealism was coined by Louis K. Meisel in 1969 and it is also sometimes labeled as Super-Realism, New Realism, Sharp Focus Realism, or Hyper-Realism. The definition for the ORIGINATORS was as follows, The Photo-Realist uses the camera, the Photo-Realist uses a mechanical or semimechanical means to transfer the information to the canvas. The Photo-Realist must have the ability to make the finished work appear photographic. The artist must have exhibited work as a Photo-Realist by 1972 to be considered one of the central Photo-Realists, the artist must have devoted at least five years to the development and exhibition of Photo-Realist work. Photorealist painting cannot exist without the photograph, in Photorealism, change and movement must be frozen in time which must then be accurately represented by the artist. Photorealists gather their imagery and information with the camera and photograph, once the photograph is developed the artist will systematically transfer the image from the photographic slide onto canvases. Usually this is either by projecting the slide onto the canvas or by using traditional grid techniques. The resulting images are often direct copies of the photograph but are usually larger than the original photograph or slide. In the UK, photorealist approaches were favoured by artists including Mike Gorman. The introduction of these European painters to a wider US audience was brought about through the 1982 Superhumanism exhibition at the Arnold Katzen Gallery, though the height of Photorealism was in the 1970s the movement continues and includes several of the original photorealists as well as many of their contemporaries. According to Meisel and Chases Photorealism at the Millennium, only eight of the original photorealists were still creating photorealist work in 2002, ten including John Baeder, newer Photorealists are building upon the foundations set by the original photorealists. Examples would be the influence of Richard Estes in works by Anthony Brunelli or the influence of Ralph Goings, however, this has led many to move on from the strict definition of photorealism as the emulation of the photograph. Photorealism is also no longer simply an American art movement, with new technology in cameras and digital equipment, artists are able to be far more precision-oriented
5.
Non-photorealistic rendering
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Non-photorealistic rendering is an area of computer graphics that focuses on enabling a wide variety of expressive styles for digital art. In contrast to traditional computer graphics, which has focused on photorealism, NPR is inspired by styles such as painting, drawing, technical illustration. NPR has appeared in movies and video games in the form of shading, as well as in scientific visualization, architectural illustration. An example of a use of this method is that of cel-shaded animation. The term non-photorealistic rendering was probably coined by David Salesin and Georges Winkenbach in a 1994 paper, many researchers find the terminology to be unsatisfying, some of the criticisms are as follows, The term photorealism has different meanings for graphics researchers and artists. For graphics researchers, it refers to an image that is visually indistinguishable from reality, in fact, graphics researchers lump the kinds of visual distortions that are used by photorealist painters into non-photorealism. Describing something by what it is not is problematic, equivalent comparisons might be non-elephant biology, or non-geometric mathematics. Many techniques that are used to create non-photorealistic images are not rendering techniques and they are modelling techniques, or post-processing techniques. The first conference on Non-Photorealistic Animation and Rendering included a discussion of alternative names. Among those suggested were expressive graphics, artistic rendering, non-realistic graphics, art-based rendering, all of these terms have been used in various research papers on the topic, but the term NPR seems to have nonetheless taken hold. The first technical meeting dedicated to NPR was the ACM sponsored Symposium on Non-Photorealistic Rendering, NPAR is traditionally co-located with the Annecy Animated Film Festival, running on even numbered years. From 2007 NPAR began to run on odd-numbered years, co-located with ACM SIGGRAPH. Three-dimensional NPR is the style that is most commonly seen in games and movies. The output from this technique is almost always a 3D model that has been modified from the original model to portray a new artistic style. In many cases, the geometry of the model is identical to the original geometry, with increased availability of programmable GPUs, shaders have allowed NPR effects to be applied to the rasterised image that is to be displayed to the screen. The majority of NPR techniques applied to 3D geometry are intended to make the scene appear two-dimensional, for enhanced legibility, the most useful technical illustrations for technical communication are not necessarily photorealistic. Non-photorealistic renderings, such as exploded view diagrams, greatly assist in showing placement of parts in a complex system. The input to a two-dimensional NPR system is most commonly an image, however, there are systems that take 3D geometry information as input and produce a 2D image or video as output
6.
3D modeling
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In 3D computer graphics, 3D modeling is the process of developing a mathematical representation of any three-dimensional surface of an object via specialized software. The product is called a 3D model and it can be displayed as a two-dimensional image through a process called 3D rendering or used in a computer simulation of physical phenomena. The model can also be created using 3D printing devices. Models may be created automatically or manually, the manual modeling process of preparing geometric data for 3D computer graphics is similar to plastic arts such as sculpting. 3D modeling software is a class of 3D computer graphics used to produce 3D models. Individual programs of this class are called modeling applications or modelers, three-dimensional models represent a physical body using a collection of points in 3D space, connected by various geometric entities such as triangles, lines, curved surfaces, etc. Being a collection of data, 3D models can be created by hand, algorithmically and their surfaces may be further defined with texture mapping. 3D models are used anywhere in 3D graphics and CAD. Actually, their use predates the use of 3D graphics on personal computers. Many computer games used pre-rendered images of 3D models as sprites before computers could render them in real-time, today, 3D models are used in a wide variety of fields. The medical industry uses detailed models of organs, these may be created with multiple 2-D image slices from an MRI or CT scan, the movie industry uses them as characters and objects for animated and real-life motion pictures. The video game industry uses them as assets for computer and video games, the science sector uses them as highly detailed models of chemical compounds. The architecture industry uses them to demonstrate proposed buildings and landscapes in lieu of traditional, physical architectural models, the engineering community uses them as designs of new devices, vehicles and structures as well as a host of other uses. In recent decades the earth science community has started to construct 3D geological models as a standard practice, 3D models can also be the basis for physical devices that are built with 3D printers or CNC machines. Almost all 3D models can be divided into two categories, solid - These models define the volume of the object they represent. Almost all visual models used in games and film are shell models, solid and shell modeling can create functionally identical objects. Shell models must be manifold to be meaningful as a real object, Polygonal meshes are by far the most common representation. Level sets are a representation for deforming surfaces which undergo many topological changes such as fluids
7.
Computer program
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A computer program is a collection of instructions that performs a specific task when executed by a computer. A computer requires programs to function, and typically executes the programs instructions in a processing unit. A computer program is written by a computer programmer in a programming language. From the program in its form of source code, a compiler can derive machine code—a form consisting of instructions that the computer can directly execute. Alternatively, a program may be executed with the aid of an interpreter. A part of a program that performs a well-defined task is known as an algorithm. A collection of programs, libraries and related data are referred to as software. Computer programs may be categorized along functional lines, such as software or system software. The earliest programmable machines preceded the invention of the digital computer, in 1801, Joseph-Marie Jacquard devised a loom that would weave a pattern by following a series of perforated cards. Patterns could be weaved and repeated by arranging the cards, in 1837, Charles Babbage was inspired by Jacquards loom to attempt to build the Analytical Engine. The names of the components of the device were borrowed from the textile industry. In the textile industry, yarn was brought from the store to be milled, the device would have had a store—memory to hold 1,000 numbers of 40 decimal digits each. Numbers from the store would then have then transferred to the mill. It was programmed using two sets of perforated cards—one to direct the operation and the other for the input variables, however, after more than 17,000 pounds of the British governments money, the thousands of cogged wheels and gears never fully worked together. During a nine-month period in 1842–43, Ada Lovelace translated the memoir of Italian mathematician Luigi Menabrea, the memoir covered the Analytical Engine. The translation contained Note G which completely detailed a method for calculating Bernoulli numbers using the Analytical Engine and this note is recognized by some historians as the worlds first written computer program. In 1936, Alan Turing introduced the Universal Turing machine—a theoretical device that can model every computation that can be performed on a Turing complete computing machine and it is a finite-state machine that has an infinitely long read/write tape. The machine can move the back and forth, changing its contents as it performs an algorithm
8.
Data structure
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In computer science, a data structure is a particular way of organizing data in a computer so that it can be used efficiently. Data structures can implement one or more abstract data types, which specify the operations that can be performed on a data structure. In comparison, a structure is a concrete implementation of the specification provided by an ADT. Different kinds of structures are suited to different kinds of applications. For example, relational databases commonly use B-tree indexes for data retrieval, Data structures provide a means to manage large amounts of data efficiently for uses such as large databases and internet indexing services. Usually, efficient data structures are key to designing efficient algorithms, some formal design methods and programming languages emphasize data structures, rather than algorithms, as the key organizing factor in software design. Data structures can be used to organize the storage and retrieval of stored in both main memory and secondary memory. Many data structures use both principles, sometimes combined in non-trivial ways, the implementation of a data structure usually requires writing a set of procedures that create and manipulate instances of that structure. The efficiency of a data structure cannot be analyzed separately from those operations, there are numerous types of data structures, generally built upon simpler primitive data types, An array is a number of elements in a specific order, typically all of the same type. Elements are accessed using an index to specify which element is required. Typical implementations allocate contiguous memory words for the elements of arrays, arrays may be fixed-length or resizable. A linked list is a collection of data elements of any type, called nodes, where each node has itself a value. The principal advantage of a linked list over an array, is that values can always be efficiently inserted and removed without relocating the rest of the list, certain other operations, such as random access to a certain element, are however slower on lists than on arrays. A record is a data structure. A record is a value that contains other values, typically in fixed number and sequence, the elements of records are usually called fields or members. A union is a structure that specifies which of a number of permitted primitive types may be stored in its instances. Contrast with a record, which could be defined to contain a float, enough space is allocated to contain the widest member datatype. A tagged union contains an additional field indicating its current type, a class is a data structure that contains data fields, like a record, as well as various methods which operate on the contents of the record
9.
Texture mapping
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Texture mapping is a method for defining high frequency detail, surface texture, or color information on a computer-generated graphic or 3D model. Its application to 3D graphics was pioneered by Edwin Catmull in 1974, texture mapping originally referred to a method that simply wrapped and mapped pixels from a texture to a 3D surface. A texture map is an image applied to the surface of a shape or polygon and this may be a bitmap image or a procedural texture. They may be stored in image file formats, referenced by 3d model formats or material definitions. They may have 1-3 dimensions, although 2 dimensions are most common for visible surfaces, for use with modern hardware, texture map data may be stored in swizzled or tiled orderings to improve cache coherency. Rendering APIs typically manage texture map resources as buffers or surfaces and they usually contain RGB color data, and sometimes an additional channel for alpha blending especially for billboards and decal overlay textures. It is possible to use the channel for other uses such as specularity. Multiple texture maps may be combined for control over specularity, normals, displacement, multiple texture images may be combined in texture atlases or array textures to reduce state changes for modern hardware. Modern hardware often supports cube map textures with multiple faces for environment mapping and they may be acquired by scanning/digital photography, authored in image manipulation software such as Photoshop, or painted onto 3D surfaces directly in a 3D paint tool such as Mudbox or zbrush. This process is akin to applying patterned paper to a white box. Every vertex in a polygon is assigned a texture coordinate and this may be done through explicit assignment of vertex attributes, manually edited in a 3D modelling package through UV unwrapping tools. It is also possible to associate a procedural transformation from 3d space to space with the material. This might be accomplished via planar projection or, alternatively, cylindrical or spherical mapping, more complex mappings may consider the distance along a surface to minimize distortion. These coordinates are interpolated across the faces of polygons to sample the texture map during rendering, UV unwrapping tools typically provide a view in texture space for manual editing of texture coordinates. Some rendering techniques such as subsurface scattering may be performed approximately by texture-space operations, multitexturing is the use of more than one texture at a time on a polygon. For instance, a light map texture may be used to light a surface as an alternative to recalculating that lighting every time the surface is rendered. Microtextures or detail textures are used to add higher frequency details, and dirt maps may add weathering and variation, modern graphics may use in excess of 10 layers for greater fidelity which are combined using shaders. Bump mapping has become popular in recent video games, as graphics hardware has become powerful enough to accommodate it in real-time, the way that samples are calculated from the texels is governed by texture filtering
10.
Lighting
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Lighting or illumination is the deliberate use of light to achieve a practical or aesthetic effect. Lighting includes the use of artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylight. Daylighting is sometimes used as the source of light during daytime in buildings. This can save energy in place of using lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance performance, improve the appearance of an area. Indoor lighting is accomplished using light fixtures, and is a key part of interior design. Lighting can also be a component of landscape projects. With the discovery of fire, the earliest form of lighting used to illuminate an area were campfires or torches. As early as 400,000 BCE, fire was kindled in the caves of Peking Man, prehistoric people used primitive oil lamps to illuminate surroundings. These lamps were made from naturally occurring materials such as rocks, shells, horns and stones, were filled with grease, lamps typically used animal or vegetable fats as fuel. Hundreds of these lamps have been found in the Lascaux caves in modern-day France, oily animals were also used as lamps after being threaded with a wick. Fireflies have been used as lighting sources, candles and glass and pottery lamps were also invented. Chandeliers were a form of light fixture. A major reduction in the cost of lighting occurred with the discovery of whale oil, in 1849, Dr. Abraham Gesner, a Canadian geologist, devised a method where kerosene could be distilled from petroleum. Earlier coal-gas methods had been used for lighting since the 1820s, gesners kerosene was cheap, easy to produce, could be burned in existing lamps, and did not produce an offensive odor as did most whale oil. It could be stored indefinitely unlike whale oil, which would eventually spoil, the American petroleum boom began in the 1850s. By the end of the decade there were 30 kerosene plants operating in the United States, the cheaper, more efficient fuel began to drive whale oil out of the market. John D. Rockefeller was most responsible for the success of kerosene
11.
Shading
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Shading refers to depicting depth perception in 3D models or illustrations by varying levels of darkness. There are various techniques of shading including cross hatching where perpendicular lines of varying closeness are drawn in a pattern to shade an area. The closer the lines are together, the darker the area appears, likewise, the farther apart the lines are, the lighter the area appears. Light patterns, such as objects having light and shaded areas, powder shading is a sketching shading method. In this style, the powder and paper stumps are used to draw a picture. The stumping powder is smooth and doesnt have any shiny particles, the paper to be used should have small grains on it so that the powder remains on the paper. Shading is performed during the process by a program called a shader. Shading alters the colors of faces in a 3D model based on the angle of the surface to a source or light sources. The first image below has the faces of the box rendered, edge lines have been rendered here as well which makes the image easier to see. The second image is the same model rendered without edge lines and it is difficult to tell where one face of the box ends and the next begins. The third image has shading enabled, which makes the image more realistic, Shading is also dependent on the lighting used. Usually, upon rendering a scene a number of different lighting techniques will be used to make the look more realistic. Different types of sources are used to give different effects. An ambient light source represents an omni-directional, fixed-intensity and fixed-color light source that affects all objects in the scene equally, upon rendering, all objects in the scene are brightened with the specified intensity and color. This type of source is mainly used to provide the scene with a basic view of the different objects in it. This is the simplest type of lighting to implement and models how light can be scattered or reflected many times producing a uniform effect. Ambient lighting can be combined with ambient occlusion to represent how exposed each point of the scene is and this produces diffuse, non-directional lighting throughout the scene, casting no clear shadows, but with enclosed and sheltered areas darkened. The result is usually similar to an overcast day
12.
Raster graphics
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Raster images are stored in image files with varying formats. A raster is technically characterized by the width and height of the image in pixels, the printing and prepress industries know raster graphics as contones. The opposite to contones is line work, usually implemented as vector graphics in digital systems, the word raster has its origins in the Latin rastrum, which is derived from radere. It originates from the scan of cathode ray tube video monitors. By association, it can refer to a rectangular grid of pixels. The word rastrum is now used to refer to a device for drawing musical staff lines, most modern computers have bitmapped displays, where each on-screen pixel directly corresponds to a small number of bits in memory. The screen is refreshed simply by scanning through pixels and coloring them according to set of bits. The refresh procedure, being speed critical, is implemented by dedicated circuitry. Most computer images are stored in raster graphics formats or compressed variations, including GIF, JPEG, and PNG, three-dimensional voxel raster graphics are employed in video games and are also used in medical imaging such as MRI scanners. GIS programs commonly use rasters that encode geographic data in the values as well as the pixel locations. Raster graphics are resolution dependent, meaning they cannot scale up to a resolution without loss of apparent quality. This property contrasts with the capabilities of graphics, which easily scale up to the quality of the device rendering them. Raster graphics deal more practically than vector graphics with photographs and photo-realistic images, typically, a resolution of 150 to 300 PPI works well for 4-color process printing. However, for printing technologies that perform color mixing through dithering rather than through overprinting, printer DPI and image PPI have a different meaning. Thus, for instance, printing an image at 250 PPI may actually require a printer setting of 1200 DPI, when an image is rendered in a raster-based image editor, the image is composed of millions of pixels. At its core, an image editor works by manipulating each individual pixel. Most pixel-based image editors work using the RGB color model, and this article is based on material taken from the Free On-line Dictionary of Computing prior to 1 November 2008 and incorporated under the relicensing terms of the GFDL, version 1.3 or later
13.
Graphics processing unit
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GPUs are used in embedded systems, mobile phones, personal computers, workstations, and game consoles. In a personal computer, a GPU can be present on a video card, the term GPU was popularized by Nvidia in 1999, who marketed the GeForce 256 as the worlds first GPU, or Graphics Processing Unit. It was presented as a processor with integrated transform, lighting, triangle setup/clipping. Rival ATI Technologies coined the visual processing unit or VPU with the release of the Radeon 9700 in 2002. Arcade system boards have been using specialized graphics chips since the 1970s, in early video game hardware, the RAM for frame buffers was expensive, so video chips composited data together as the display was being scanned out on the monitor. Fujitsus MB14241 video shifter was used to accelerate the drawing of sprite graphics for various 1970s arcade games from Taito and Midway, such as Gun Fight, Sea Wolf, the Namco Galaxian arcade system in 1979 used specialized graphics hardware supporting RGB color, multi-colored sprites and tilemap backgrounds. The Galaxian hardware was used during the golden age of arcade video games, by game companies such as Namco, Centuri, Gremlin, Irem, Konami, Midway, Nichibutsu, Sega. In the home market, the Atari 2600 in 1977 used a video shifter called the Television Interface Adaptor,6502 machine code subroutines could be triggered on scan lines by setting a bit on a display list instruction. ANTIC also supported smooth vertical and horizontal scrolling independent of the CPU and it became one of the best known of what were known as graphics processing units in the 1980s. The Williams Electronics arcade games Robotron,2084, Joust, Sinistar, in 1985, the Commodore Amiga featured a custom graphics chip, with a blitter unit accelerating bitmap manipulation, line draw, and area fill functions. Also included is a coprocessor with its own instruction set, capable of manipulating graphics hardware registers in sync with the video beam. In 1986, Texas Instruments released the TMS34010, the first microprocessor with on-chip graphics capabilities and it could run general-purpose code, but it had a very graphics-oriented instruction set. In 1990-1992, this chip would become the basis of the Texas Instruments Graphics Architecture Windows accelerator cards, in 1987, the IBM8514 graphics system was released as one of the first video cards for IBM PC compatibles to implement fixed-function 2D primitives in electronic hardware. Fujitsu later competed with the FM Towns computer, released in 1989 with support for a full 16,777,216 color palette, in 1988, the first dedicated polygonal 3D graphics boards were introduced in arcades with the Namco System 21 and Taito Air System. In 1991, S3 Graphics introduced the S3 86C911, which its designers named after the Porsche 911 as an implication of the performance increase it promised. The 86C911 spawned a host of imitators, by 1995, all major PC graphics chip makers had added 2D acceleration support to their chips. By this time, fixed-function Windows accelerators had surpassed expensive general-purpose graphics coprocessors in Windows performance, throughout the 1990s, 2D GUI acceleration continued to evolve. As manufacturing capabilities improved, so did the level of integration of graphics chips, arcade systems such as the Sega Model 2 and Namco Magic Edge Hornet Simulator in 1993 were capable of hardware T&L years before appearing in consumer graphics cards
14.
Central processing unit
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The computer industry has used the term central processing unit at least since the early 1960s. The form, design and implementation of CPUs have changed over the course of their history, most modern CPUs are microprocessors, meaning they are contained on a single integrated circuit chip. An IC that contains a CPU may also contain memory, peripheral interfaces, some computers employ a multi-core processor, which is a single chip containing two or more CPUs called cores, in that context, one can speak of such single chips as sockets. Array processors or vector processors have multiple processors that operate in parallel, there also exists the concept of virtual CPUs which are an abstraction of dynamical aggregated computational resources. Early computers such as the ENIAC had to be rewired to perform different tasks. Since the term CPU is generally defined as a device for software execution, the idea of a stored-program computer was already present in the design of J. Presper Eckert and John William Mauchlys ENIAC, but was initially omitted so that it could be finished sooner. On June 30,1945, before ENIAC was made, mathematician John von Neumann distributed the paper entitled First Draft of a Report on the EDVAC and it was the outline of a stored-program computer that would eventually be completed in August 1949. EDVAC was designed to perform a number of instructions of various types. Significantly, the programs written for EDVAC were to be stored in high-speed computer memory rather than specified by the wiring of the computer. This overcame a severe limitation of ENIAC, which was the considerable time, with von Neumanns design, the program that EDVAC ran could be changed simply by changing the contents of the memory. Early CPUs were custom designs used as part of a larger, however, this method of designing custom CPUs for a particular application has largely given way to the development of multi-purpose processors produced in large quantities. This standardization began in the era of discrete transistor mainframes and minicomputers and has accelerated with the popularization of the integrated circuit. The IC has allowed increasingly complex CPUs to be designed and manufactured to tolerances on the order of nanometers, both the miniaturization and standardization of CPUs have increased the presence of digital devices in modern life far beyond the limited application of dedicated computing machines. Modern microprocessors appear in electronic devices ranging from automobiles to cellphones, the so-called Harvard architecture of the Harvard Mark I, which was completed before EDVAC, also utilized a stored-program design using punched paper tape rather than electronic memory. Relays and vacuum tubes were used as switching elements, a useful computer requires thousands or tens of thousands of switching devices. The overall speed of a system is dependent on the speed of the switches, tube computers like EDVAC tended to average eight hours between failures, whereas relay computers like the Harvard Mark I failed very rarely. In the end, tube-based CPUs became dominant because the significant speed advantages afforded generally outweighed the reliability problems, most of these early synchronous CPUs ran at low clock rates compared to modern microelectronic designs. Clock signal frequencies ranging from 100 kHz to 4 MHz were very common at this time, the design complexity of CPUs increased as various technologies facilitated building smaller and more reliable electronic devices
15.
Rendering equation
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It was simultaneously introduced into computer graphics by David Immel et al. and James Kajiya in 1986. The various realistic rendering techniques in computer graphics attempt to solve this equation, the physical basis for the rendering equation is the law of conservation of energy. Assuming that L denotes radiance, we have that at each position and direction, the outgoing light is the sum of the emitted light. The reflected light itself is the sum from all directions of the incoming light multiplied by the surface reflection and this is often written as cos θ i. Two noteworthy features are, its linearity—it is composed only of multiplications and additions and these mean a wide range of factorings and rearrangements of the equation are possible. It is a Fredholm integral equation of the kind, similar to those that arise in quantum field theory. Note this equations spectral and time dependence — L o may be sampled at or integrated over sections of the spectrum to obtain, for example. A pixel value for a frame in an animation may be obtained by fixing t. Note that a solution to the equation is the function L o. The function L i is related to L o via a ray-tracing operation, solving the rendering equation for any given scene is the primary challenge in realistic rendering. One approach to solving the equation is based on finite element methods, another approach using Monte Carlo methods has led to many different algorithms including path tracing, photon mapping, and Metropolis light transport, among others. Although the equation is general, it does not capture every aspect of light reflection. Lecture notes from Stanford University course CS 348B, Computer Graphics, Image Synthesis Techniques
16.
3D computer graphics
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Such 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, 3D computer graphics are often referred to as 3D models. Apart from the graphic, the model is contained within the graphical data file. However, there are differences, a 3D model is the 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 used in non-graphical computer simulations and calculations. With 3D printing, 3D models are rendered into a 3D physical representation of the model. William Fetter was credited with coining the term computer graphics in 1961 to describe his work at Boeing, 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 Mitazawa, models can also be produced procedurally or via physical simulation. Basically, a 3D model is formed from points called vertices that define the shape, a polygon is an area formed from at least three vertexes. 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. Before rendering into an image, objects must be out in a scene. This defines spatial relationships between objects, including location and size, Animation refers to the temporal description of an object. These techniques are used in combination. As with animation, physical simulation also specifies motion, 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 and scattering and this step is usually performed using 3D computer graphics software or a 3D graphics API. Altering the scene into a form for rendering also involves 3D projection. There are a multitude of websites designed to help, educate, some are managed by software developers and content providers, but there are standalone sites as well. These communities allow for members to seek advice, post tutorials, not all computer graphics that appear 3D are based on a wireframe model
17.
Architectural rendering
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Architectural rendering, or architectural illustration, is the art of creating two-dimensional images or animations showing the attributes of a proposed architectural design. Images that are generated by a computer using three-dimensional modeling software or other software for presentation purposes are commonly termed Computer Generated Renderings. Some methods create simple flat images or images with basic shadows, a popular technique uses sophisticated software to approximate accurate lighting and materials. This technique is referred to as a Photo Real rendering. Renderings are usually created for presentation, marketing and design analysis purposes and it also makes it possible to make design related decisions well before the building is actually built. Thus it helps experimenting with building design and its visual aspects, until 3D computer modeling became common, most architectural renderings were created by hand. There are still many architectural illustrators who create renderings entirely by hand, some hand illustrators use a combination of hand and computer generated linework. It is the Societys highest award, the CGarchitect Architectural 3D Awards are awarded by CGarchitect. com in recognition of outstanding achievement in the field of computer-generated architectural rendering. Traditionally rendering techniques were taught in a master class practice, where a student works creatively with a mentor in the study of fine arts, contemporary architects use hand-drawn sketches, pen and ink drawings, and watercolor renderings to represent their design with the vision of an artist. Computer generated graphics is the newest medium to be utilized by architectural illustrators, Architectural animation 3D rendering Architectural illustrator Concept art Museum for Architectural Drawing, Berlin, Germany
18.
Video game
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A video game is an electronic game that involves interaction with a user interface to generate visual feedback on a video device such as a TV screen or computer monitor. The word video in video game referred to a raster display device. Some theorists categorize video games as an art form, but this designation is controversial, the electronic systems used to play video games are known as platforms, examples of these are personal computers and video game consoles. These platforms range from large mainframe computers to small handheld computing devices, the input device used for games, the game controller, varies across platforms. Common controllers include gamepads, joysticks, mouse devices, keyboards, the touchscreens of mobile devices, and buttons, or even, with the Kinect sensor, a persons hands and body. Players typically view the game on a screen or television or computer monitor, or sometimes on virtual reality head-mounted display goggles. There are often game sound effects, music and, in the 2010s, some games in the 2000s include haptic, vibration-creating effects, force feedback peripherals and virtual reality headsets. In the 2010s, the game industry is of increasing commercial importance, with growth driven particularly by the emerging Asian markets and mobile games. As of 2015, video games generated sales of USD74 billion annually worldwide, early games used interactive electronic devices with various display formats. The earliest example is from 1947—a Cathode ray tube Amusement Device was filed for a patent on 25 January 1947, by Thomas T. Goldsmith Jr. and Estle Ray Mann, and issued on 14 December 1948, as U. S. Written by MIT students Martin Graetz, Steve Russell, and Wayne Wiitanens on a DEC PDP-1 computer in 1961, and the hit ping pong-style Pong, used the DEC PDP-1s vector display to have two spaceships battle each other. In 1971, Computer Space, created by Nolan Bushnell and Ted Dabney, was the first commercially sold and it used a black-and-white television for its display, and the computer system was made of 74 series TTL chips. The game was featured in the 1973 science fiction film Soylent Green, Computer Space was followed in 1972 by the Magnavox Odyssey, the first home console. Modeled after a late 1960s prototype console developed by Ralph H. Baer called the Brown Box and these were followed by two versions of Ataris Pong, an arcade version in 1972 and a home version in 1975 that dramatically increased video game popularity. The commercial success of Pong led numerous other companies to develop Pong clones and their own systems, the game inspired arcade machines to become prevalent in mainstream locations such as shopping malls, traditional storefronts, restaurants, and convenience stores. The game also became the subject of articles and stories on television and in newspapers and magazines. Space Invaders was soon licensed for the Atari VCS, becoming the first killer app, the term platform refers to the specific combination of electronic components or computer hardware which, in conjunction with software, allows a video game to operate. The term system is commonly used
19.
Simulation
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Simulation is the imitation of the operation of a real-world process or system over time. The model represents the system itself, whereas the simulation represents the operation of the system over time, Simulation is used in many contexts, such as simulation of technology for performance optimization, safety engineering, testing, training, education, and video games. Often, computer experiments are used to study simulation models, Simulation is also used with scientific modelling of natural systems or human systems to gain insight into their functioning, as in economics. Simulation can be used to show the real effects of alternative conditions. Physical simulation refers to simulation in which objects are substituted for the real thing. These physical objects are chosen because they are smaller or cheaper than the actual object or system. Simulation Fidelity is used to describe the accuracy of a simulation, Fidelity is broadly classified as 1 of 3 categories, low, medium, and high. Simulation in failure analysis refers to simulation in which we create environment/conditions to identify the cause of equipment failure and this was the best and fastest method to identify the failure cause. A computer simulation is an attempt to model a real-life or hypothetical situation on a computer so that it can be studied to see how the system works, by changing variables in the simulation, predictions may be made about the behaviour of the system. It is a tool to investigate the behaviour of the system under study. A good example of the usefulness of using computers to simulate can be found in the field of network traffic simulation, in such simulations, the model behaviour will change each simulation according to the set of initial parameters assumed for the environment. Computer simulation is used as an adjunct to, or substitution for. Several software packages exist for running computer-based simulation modeling that makes all the modeling almost effortless, modern usage of the term computer simulation may encompass virtually any computer-based representation. The computer simulates the subject machine, accordingly, in theoretical computer science the term simulation is a relation between state transition systems, useful in the study of operational semantics. Less theoretically, an application of computer simulation is to simulate computers using computers. For example, simulators have been used to debug a microprogram or sometimes commercial application programs, simulators may also be used to interpret fault trees, or test VLSI logic designs before they are constructed. Symbolic simulation uses variables to stand for unknown values, in the field of optimization, simulations of physical processes are often used in conjunction with evolutionary computation to optimize control strategies. Simulation is extensively used for educational purposes and it is frequently used by way of adaptive hypermedia
20.
Film
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A film, also called a movie, motion picture, theatrical film or photoplay, is a series of still images which, when shown on a screen, creates the illusion of moving images due to the phi phenomenon. This optical illusion causes the audience to perceive continuous motion between separate objects viewed rapidly in succession, the process of filmmaking is both an art and an industry. The word cinema, short for cinematography, is used to refer to the industry of films. Films were originally recorded onto plastic film through a photochemical process, the adoption of CGI-based special effects led to the use of digital intermediates. Most contemporary films are now fully digital through the process of production, distribution. Films recorded in a form traditionally included an analogous optical soundtrack. It runs along a portion of the film exclusively reserved for it and is not projected, Films are cultural artifacts created by specific cultures. They reflect those cultures, and, in turn, affect them, Film is considered to be an important art form, a source of popular entertainment, and a powerful medium for educating—or indoctrinating—citizens. The visual basis of film gives it a power of communication. Some films have become popular worldwide attractions by using dubbing or subtitles to translate the dialog into the language of the viewer, some have criticized the film industrys glorification of violence and its potentially negative treatment of women. The individual images that make up a film are called frames, the perception of motion is due to a psychological effect called phi phenomenon. The name film originates from the fact that film has historically been the medium for recording and displaying motion pictures. Many other terms exist for a motion picture, including picture, picture show, moving picture, photoplay. The most common term in the United States is movie, while in Europe film is preferred. Terms for the field, in general, include the big screen, the screen, the movies, and cinema. In early years, the sheet was sometimes used instead of screen. Preceding film in origin by thousands of years, early plays and dances had elements common to film, scripts, sets, costumes, production, direction, actors, audiences, storyboards, much terminology later used in film theory and criticism apply, such as mise en scène. Owing to the lack of any technology for doing so, the moving images, the magic lantern, probably created by Christiaan Huygens in the 1650s, could be used to project animation, which was achieved by various types of mechanical slides
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Optics
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Optics is the branch of physics which involves the behaviour and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behaviour of visible, ultraviolet, and infrared light, because light is an electromagnetic wave, other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for using the classical description of light. Complete electromagnetic descriptions of light are, however, often difficult to apply in practice, practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of rays that travel in straight lines, physical optics is a more comprehensive model of light, which includes wave effects such as diffraction and interference that cannot be accounted for in geometric optics. Historically, the model of light was developed first, followed by the wave model of light. Progress in electromagnetic theory in the 19th century led to the discovery that waves were in fact electromagnetic radiation. Some phenomena depend on the fact that light has both wave-like and particle-like properties, explanation of these effects requires quantum mechanics. When considering lights particle-like properties, the light is modelled as a collection of particles called photons, quantum optics deals with the application of quantum mechanics to optical systems. Optical science is relevant to and studied in many related disciplines including astronomy, various engineering fields, photography, practical applications of optics are found in a variety of technologies and everyday objects, including mirrors, lenses, telescopes, microscopes, lasers, and fibre optics. Optics began with the development of lenses by the ancient Egyptians and Mesopotamians, the earliest known lenses, made from polished crystal, often quartz, date from as early as 700 BC for Assyrian lenses such as the Layard/Nimrud lens. The ancient Romans and Greeks filled glass spheres with water to make lenses, the word optics comes from the ancient Greek word ὀπτική, meaning appearance, look. Greek philosophy on optics broke down into two opposing theories on how vision worked, the theory and the emission theory. The intro-mission approach saw vision as coming from objects casting off copies of themselves that were captured by the eye, plato first articulated the emission theory, the idea that visual perception is accomplished by rays emitted by the eyes. He also commented on the parity reversal of mirrors in Timaeus, some hundred years later, Euclid wrote a treatise entitled Optics where he linked vision to geometry, creating geometrical optics. Ptolemy, in his treatise Optics, held a theory of vision, the rays from the eye formed a cone, the vertex being within the eye. The rays were sensitive, and conveyed back to the observer’s intellect about the distance. He summarised much of Euclid and went on to describe a way to measure the angle of refraction, during the Middle Ages, Greek ideas about optics were resurrected and extended by writers in the Muslim world
22.
Visual system
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The visual system is the part of the central nervous system which gives organisms the ability to process visual detail, as well as enabling the formation of several non-image photo response functions. It detects and interprets information from visible light to build a representation of the surrounding environment, the psychological process of visual information is known as visual perception, a lack of which is called blindness. Non-image forming visual functions, independent of perception, include the pupillary light reflex. This article mostly describes the system of mammals, humans in particular. Together the cornea and lens refract light into a small image, the retina transcribes this image into electrical pulses using rods and cones. The optic nerve then carries these pulses through the optic canal, upon reaching the optic chiasm the nerve fibers decussate. The fibers then branch and terminate in three places, most end in the lateral geniculate nucleus. Before the LGN forwards the pulses to V1 of the visual cortex it gauges the range of objects, the LGN also sends some fibers to V2 and V3. V1 performs edge-detection to understand spatial organization, V2 both forwards pulses to V1 and receives them. Pulvinar is responsible for saccade and visual attention, V2 serves much the same function as V1, however, it also handles illusory contours, determining depth by comparing left and right pulses, and foreground distinguishment. V3 helps process ‘global motion’ of objects, V3 connects to V1, V2, and the inferior temporal cortex. V4 recognizes simple shapes, gets input from V1, V2, V3, LGN, v5’s outputs include V4 and its surrounding area, and eye-movement motor cortices. V5’s functionality is similar to that of the other V’s, however, V6 works in conjunction with V5 on motion analysis. V5 analyzes self-motion, whereas V6 analyzes motion of objects relative to the background, v6’s primary input is V1, with V5 additions. V6 houses the topographical map for vision, V6 outputs to the region directly around it. V6A has direct connections to arm-moving cortices, including the premotor cortex, the inferior temporal gyrus recognizes complex shapes, objects, and faces or, in conjunction with the hippocampus, creates new memories. The pretectal area is seven unique nuclei, anterior, posterior and medial pretectal nuclei inhibit pain, aid in REM, and aid the accommodation reflex, respectively. The Edinger-Westphal nucleus moderates pupil dilation and aids in convergence of the eyes, nuclei of the optic tract are involved in smooth pursuit eye movement and the accommodation reflex, as well as REM
23.
Mathematics
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Mathematics is the study of topics such as quantity, structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope, Mathematicians seek out patterns and use them to formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proof, when mathematical structures are good models of real phenomena, then mathematical reasoning can provide insight or predictions about nature. Through the use of abstraction and logic, mathematics developed from counting, calculation, measurement, practical mathematics has been a human activity from as far back as written records exist. The research required to solve mathematical problems can take years or even centuries of sustained inquiry, rigorous arguments first appeared in Greek mathematics, most notably in Euclids Elements. Galileo Galilei said, The universe cannot be read until we have learned the language and it is written in mathematical language, and the letters are triangles, circles and other geometrical figures, without which means it is humanly impossible to comprehend a single word. Without these, one is wandering about in a dark labyrinth, carl Friedrich Gauss referred to mathematics as the Queen of the Sciences. Benjamin Peirce called mathematics the science that draws necessary conclusions, David Hilbert said of mathematics, We are not speaking here of arbitrariness in any sense. Mathematics is not like a game whose tasks are determined by arbitrarily stipulated rules, rather, it is a conceptual system possessing internal necessity that can only be so and by no means otherwise. Albert Einstein stated that as far as the laws of mathematics refer to reality, they are not certain, Mathematics is essential in many fields, including natural science, engineering, medicine, finance and the social sciences. Applied mathematics has led to entirely new mathematical disciplines, such as statistics, Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind. There is no clear line separating pure and applied mathematics, the history of mathematics can be seen as an ever-increasing series of abstractions. The earliest uses of mathematics were in trading, land measurement, painting and weaving patterns, in Babylonian mathematics elementary arithmetic first appears in the archaeological record. Numeracy pre-dated writing and numeral systems have many and diverse. Between 600 and 300 BC the Ancient Greeks began a study of mathematics in its own right with Greek mathematics. Mathematics has since been extended, and there has been a fruitful interaction between mathematics and science, to the benefit of both. Mathematical discoveries continue to be made today, the overwhelming majority of works in this ocean contain new mathematical theorems and their proofs. The word máthēma is derived from μανθάνω, while the modern Greek equivalent is μαθαίνω, in Greece, the word for mathematics came to have the narrower and more technical meaning mathematical study even in Classical times
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Software engineering
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Software engineering is the application of engineering to the development of software in a systematic method. Practitioners quickly realized that this design was not flexible and came up with the stored program architecture or von Neumann architecture, thus the division between hardware and software began with abstraction being used to deal with the complexity of computing. Programming languages started to appear in the early 1950s and this was another major step in abstraction. Major languages such as Fortran, ALGOL, and COBOL were released in the late 1950s to deal with scientific, algorithmic, the conference was attended by international experts on software who agreed on defining best practices for software grounded in the application of engineering. The result of the conference is a report that defines how software should be developed, the original report is publicly available. Engineering already addresses all issues, hence the same principles used in engineering can be applied to software. The widespread lack of best practices for software at the time was perceived as a software crisis, barry W. Boehm documented several key advances to the field in his 1981 book, Software Engineering Economics. These include his Constructive Cost Model, which relates software development effort for a program, in man-years T, T = k ∗ The book analyzes sixty-three software projects and concludes the cost of fixing errors escalates as the project moves toward field use. The book also asserts that the key driver of software cost is the capability of the development team. Watts Humphrey founded the SEI Software Process Program, aimed at understanding and managing the software engineering process and his 1989 book, Managing the Software Process, asserts that the Software Development Process can and should be controlled, measured, and improved. Modern, generally accepted best-practices for software engineering have been collected by the ISO/IEC JTC 1/SC7 subcommittee, Software engineering can be divided into 15 sub-disciplines. They are, Software requirements, The elicitation, analysis, specification, Software design, The process of defining the architecture, components, interfaces, and other characteristics of a system or component. It is also defined as the result of that process, Software construction, The detailed creation of working, meaningful software through a combination of coding, verification, unit testing, integration testing, and debugging. Software testing, An empirical, technical investigation conducted to provide stakeholders with information about the quality of the product or service under test, Software maintenance, The totality of activities required to provide cost-effective support to software. Software development process, The definition, implementation, assessment, measurement, management, change, many software engineers enter the profession by obtaining a university degree or training at a vocational school. One standard international curriculum for undergraduate software engineering degrees was defined by the CCSE, in addition to university education, many companies sponsor internships for students wishing to pursue careers in information technology. These internships can introduce the student to interesting real-world tasks that typical software engineers encounter every day, similar experience can be gained through military service in software engineering. Legal requirements for the licensing or certification of professional software engineers vary around the World, in Canada, there is a legal requirement to have P. Eng when one wants to use the title engineer or practice software engineering
25.
Wire-frame model
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A wire-frame model is a visual presentation of a 3-dimensional or physical object used in 3D computer graphics. It is created by specifying each edge of the object where two mathematically continuous smooth surfaces meet, or by connecting an objects constituent vertices using straight lines or curves. The object is projected into space by drawing lines at the location of each edge. The term wire frame comes from designers using metal wire to represent the shape of solid objects. 3D wire frame allows to construct and manipulate solids and solid surfaces, the 3D solid modeling technique efficiently draws higher quality representations of solids than the conventional line drawing. Using a wire-frame model allows visualization of the design structure of a 3D model. Traditional two-dimensional views and drawings can be created by appropriate rotation of the object, since wire-frame renderings are relatively simple and fast to calculate, they are often used in cases where a high screen frame rate is needed. When greater graphical detail is desired, surface textures can be added automatically after completion of the rendering of the wire frame. This allows the designer to quickly review solids or rotate the object to new desired views without long delays associated with more realistic rendering, the wire frame format is also well suited and widely used in programming tool paths for direct numerical control machine tools. Hand-drawn wire-frame-like illustrations date back as far as the Italian Renaissance, wire-frame models are also used as the input for computer-aided manufacturing. There are mainly three types of 3D CAD models, wire frame is one of them and it is the most abstract and least realistic. Other types of 3D CAD models are surface and solid and this method of modelling consists of only lines, points and curves defining the edges of an object. Wireframing is one of the used in geometric modelling systems. A wireframe model represents the shape of an object with its characteristic lines. There are two types of modelling, Pros and Cons. In Pros user gives a simple input to create a shape and it is useful in developing systems. While in Cons wireframe model, it does not include information about inside and outside boundary surfaces, today, wireframe models are used to define complex solid objects. The designer makes a model of a solid object, and then the CAD operator reconstructs the object
26.
Bitmap textures
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Textures can be built as a large image, larger than the final destination so as to fill the complete area without repeating the image. Also bitmap textures can be created to be used as patterns to fill an infinite area. The borders of these patterns or small textures should be treated to give an appearance when applied to an image, unless, of course. When designed for print, textures should be created in high-resolution in order to achieve results in the final print. On the other side, if these textures are meant to be used in multimedia, 3d animation or web design, they should be created in a maximum resolution that equals the one of the final display. If creating a texture with a computer is not an option, then textures can be obtained by purchasing stock images collections and this article was taken from The Photoshop Roadmap with written permission. Procedural textures Photoshop textures and backgrounds tutorials Photoshop CS Tutorial listings, textures, layouts, high Resolution Photoshop textures and backgrounds
27.
Bump mapping
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Bump mapping is a technique in computer graphics for simulating bumps and wrinkles on the surface of an object. This is achieved by perturbing the surface normals of the object, the result is an apparently bumpy surface rather than a smooth surface although the surface of the underlying object is not changed. Bump mapping was introduced by James Blinn in 1978, Normal mapping is the most common variation of bump mapping used. Bump mapping is a technique in computer graphics to make a rendered surface look more realistic by simulating small displacements of the surface, however, unlike displacement mapping, the surface geometry is not modified. Instead only the normal is modified as if the surface had been displaced. The modified surface normal is used for lighting calculations giving the appearance of detail instead of a smooth surface. Bump mapping is much faster and consumes less resources for the level of detail compared to displacement mapping because the geometry remains unchanged. There are also extensions which modify other features in addition to increasing the sense of depth. Parallax mapping is one such extension, the primary limitation with bump mapping is that it perturbs only the surface normals without changing the underlying surface itself. Silhouettes and shadows therefore remain unaffected, which is noticeable for larger simulated displacements. This limitation can be overcome by techniques including displacement mapping where bumps are applied to the surface or using an isosurface, there are two primary methods to perform bump mapping. The first uses a map for simulating the surface displacement yielding the modified normal. This is the method invented by Blinn and is usually what is referred to as bump mapping unless specified, the steps of this method are summarized as follows. Before a lighting calculation is performed for each point on the objects surface. Calculate the surface normal of the heightmap, typically using the finite difference method, combine the surface normal from step two with the true surface normal so that the combined normal points in a new direction. Calculate the interaction of the new surface with lights in the scene using, for example. The result is a surface that appears to have real depth, the algorithm also ensures that the surface appearance changes as lights in the scene are moved around. The other method is to specify a normal map which contains the normal for each point on the surface directly
28.
Research and development
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Research and development, also known in Europe as research and technical development, is a general term for activities in connection with corporate or governmental innovation. Research and development is situated at the front end of the life cycle. R&D differs from the vast majority of activities in that it is not intended to yield immediate profit, and generally carries greater risk. New product design and development is more often not a crucial factor in the survival of a company. In an industry that is changing fast, firms must continually revise their design and this is necessary due to continuous technology change and development as well as other competitors and the changing preference of customers. Without an R&D program, a firm must rely on strategic alliances, acquisitions, a system driven by marketing is one that puts the customer needs first, and produces goods that are known to sell. Market research is carried out, which establishes what is needed, if the development is technology driven R&D is directed toward developing products to meet the unmet need. Statistics on organizations devoted to R&D may express the state of an industry, some common measures include, budgets, numbers of patents or on rates of peer-reviewed publications. Bank ratios are one of the best measures, because they are maintained, public. In the United States, a ratio of research and development for an industrial company is about 3. 5% of revenues. A high technolog company, such as a manufacturer, might spend 7% or a pharmaceutical companies such as Merck & Co.14. 1% or Novartis 15. 1%. That is, gross profits will be as much as 90% of the sales cost, with manufacturing costing only 10% of the product price, most industrial companies get 40% revenues only. On a technical level, high tech organizations explore ways to re-purpose and they often reuse advanced manufacturing processes, expensive safety certifications, specialized embedded software, computer-aided design software, electronic designs and mechanical subsystems. Research from 2000 has shown that firms with a persistent R&D strategy outperform those with an irregular or no R&D investment program. Research and development are very difficult to manage, since the feature of research is that the researchers do not know in advance exactly how to accomplish the desired result. As a result, higher R&D spending does not guarantee more creativity, research is the most risky financing area because both the development of an invention and its successful realization carries uncertainty including the profitability of the invention. One way of reducing the uncertainty of researching know-hows is to obtain already researched know-hows, president Barack Obama requested $147.696 billion for research & development in FY2012. Much of this spending was devoted to research on the mechanisms of disease
29.
Distance fog
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Distance fog is a technique used in 3D computer graphics to enhance the perception of distance by shading distant objects differently. This technique simulates the effect of scattering, which causes more distant objects to appear lower in contrast. Fogging is another use of fog in mid-to-late 1990s games, when processing power was not enough to render far viewing distances. Silent Hill uniquely worked fogging into the storyline, with the eponymous town being consumed by a dense layer of fog as the result of the player having entered an alternate reality. The application of fogging was so well received as a technique that it has appeared in each of the games sequels
30.
Shadow
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A shadow is a dark area where light from a light source is blocked by an opaque object. It occupies all of the volume behind an object with light in front of it. The cross section of a shadow is a silhouette, or a reverse projection of the object blocking the light. A point source of light casts only a shadow, called an umbra. For a non-point or extended source of light, the shadow is divided into the umbra, penumbra and antumbra, the wider the light source, the more blurred the shadow becomes. If two penumbras overlap, the appear to attract and merge. This is known as the Shadow Blister Effect, the outlines of the shadow zones can be found by tracing the rays of light emitted by the outermost regions of the extended light source. The umbra region does not receive any direct light from any part of the light source, a viewer located in the umbra region cannot directly see any part of the light source. By contrast, the penumbra is illuminated by some parts of the light source, a viewer located in the penumbra region will see the light source, but it is partially blocked by the object casting the shadow. If there is more than one source, there will be several shadows, with the overlapping parts darker. The more diffuse the lighting is, the softer and more indistinct the shadow outlines become, the lighting of an overcast sky produces few visible shadows. The absence of diffusing atmospheric effects in the vacuum of outer space produces shadows that are stark, for a person or object touching the surface where the shadow is projected the shadows converge at the point of contact. A shadow shows, apart from distortion, the image as the silhouette when looking at the object from the sun-side. The names umbra, penumbra and antumbra are often used for the shadows cast by objects, though they are sometimes used to describe levels of darkness. An astronomical object casts human-visible shadows when its apparent magnitude is equal or lower than -4, currently the only astronomical objects able to produce visible shadows on Earth are the sun, the moon and, in the right conditions, Venus or Jupiter. A shadow cast by the Earth on the Moon is a lunar eclipse, conversely, a shadow cast by the Moon on the Earth is a solar eclipse. The sun casts shadows which change dramatically through the day, the length of a shadow cast on the ground is proportional to the cotangent of the suns elevation angle—its angle θ relative to the horizon. Near sunrise and sunset, when θ = 0° and cot = ∞, if the sun passes directly overhead, then θ = 90°, cot =0, and shadows are cast directly underneath objects
31.
Umbra, penumbra and antumbra
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The umbra, penumbra and antumbra are three distinct parts of a shadow, created by any light source after impinging on an opaque object. For a point source only the umbra is cast and these names are most often used for the shadows cast by celestial bodies, though they are sometimes used to describe levels of darkness, such as in sunspots. The umbra is the innermost and darkest part of a shadow, an observer in the umbra experiences a total eclipse. The umbra of a round body occluding a round light source forms a circular cone, to a viewer at the cones apex. The distance from the Moon to the apex of its umbra is roughly equal to that between the Moon and Earth, because the Earth is 3.7 times wider than the Moon, its umbra extends correspondingly farther, roughly 1.4 million kilometers. The penumbra is the region in only a portion of the light source is obscured by the occluding body. An observer in the experiences a partial eclipse. An alternative definition is that the penumbra is the region where some or all of the source is obscured. For example, NASAs Navigation and Ancillary Information Facility defines that a body in the umbra is also within the penumbra, the antumbra is the region from which the occluding body appears entirely contained within the disc of the light source. An observer in this region experiences an annular eclipse, in which a ring is visible around the eclipsing body. If the observer moves closer to the source, the skirt apparent size of the occluding body increases until it causes a full umbra
32.
Reflection (computer graphics)
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Reflection in computer graphics is used to emulate reflective objects like mirrors and shiny surfaces. Reflection on a surface like wood or tile can add to the photorealistic effects of a 3D rendering. Polished - A polished reflection is a reflection, like a mirror or chrome. Blurry - A blurry reflection means that tiny random bumps on the surface of the cause the reflection to be blurry. Metallic - A reflection is metallic if the highlights and reflections retain the color of the reflective object, glossy - This term can be misused. Sometimes, it is a setting which is the opposite of blurry, however, some people use the term glossy reflection as a synonym for blurred reflection. Glossy used in context means that the reflection is actually blurred. Mirrors are usually almost 100% reflective, normal objects reflect light and colors in the original color of the object being reflected. Metallic objects reflect lights and colors altered by the color of the object itself. Many materials are imperfect reflectors, where the reflections are blurred to various degrees due to surface roughness that scatters the rays of the reflections, fully glossy reflection, shows highlights from light sources, but does not show a clear reflection from objects. Illumination model Ray tracing Rendering Specular reflection Wet floor effect
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Transparency and translucency
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In the field of optics, transparency is the physical property of allowing light to pass through the material without being scattered. On a macroscopic scale, the photons can be said to follow Snells Law, in other words, a translucent medium allows the transport of light while a transparent medium not only allows the transport of light but allows for image formation. The opposite property of translucency is opacity, transparent materials appear clear, with the overall appearance of one color, or any combination leading up to a brilliant spectrum of every color. When light encounters a material, it can interact with it in different ways. These interactions depend on the wavelength of the light and the nature of the material, photons interact with an object by some combination of reflection, absorption and transmission. Some materials, such as glass and clean water, transmit much of the light that falls on them and reflect little of it. Many liquids and aqueous solutions are highly transparent, absence of structural defects and molecular structure of most liquids are mostly responsible for excellent optical transmission. Materials which do not transmit light are called opaque, many such substances have a chemical composition which includes what are referred to as absorption centers. Many substances are selective in their absorption of light frequencies. They absorb certain portions of the spectrum while reflecting others. The frequencies of the spectrum which are not absorbed are either reflected or transmitted for our physical observation and this is what gives rise to color. The attenuation of light of all frequencies and wavelengths is due to the mechanisms of absorption. Transparency can provide almost perfect camouflage for animals able to achieve it and this is easier in dimly-lit or turbid seawater than in good illumination. Many marine animals such as jellyfish are highly transparent, at the atomic or molecular level, physical absorption in the infrared portion of the spectrum depends on the frequencies of atomic or molecular vibrations or chemical bonds, and on selection rules. Nitrogen and oxygen are not greenhouse gases because there is no absorption because there is no molecular dipole moment. With regard to the scattering of light, the most critical factor is the scale of any or all of these structural features relative to the wavelength of the light being scattered. Primary material considerations include, Crystalline structure, whether or not the atoms or molecules exhibit the long-range order evidenced in crystalline solids, glassy structure, scattering centers include fluctuations in density or composition. Microstructure, scattering centers include internal surfaces such as boundaries, crystallographic defects
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Transparency (graphic)
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Transparency is possible in a number of graphics file formats. The term transparency is used in various ways by different people, of course, only part of a graphic should be fully transparent, or there would be nothing to see. More complex is partial transparency or translucency where the effect is achieved that a graphic is partially transparent in the way as colored glass. Since ultimately a printed page or computer or television screen can only be one color at a point, there are many different ways to mix colors, so in some cases transparency is ambiguous. In addition, transparency is often an extra for a graphics format, raster file formats that support transparency include GIF, PNG, BMP, TIFF, and JPEG2000, through either a transparent color or an alpha channel. Most vector formats implicitly support transparency because they simply avoid putting any objects at a given point, for vector graphics this may not strictly be seen as transparency, but it requires much of the same careful programming as transparency in raster formats. More complex vector formats may allow transparency combinations between the elements within the graphic, as well as that above, a suitable raster graphics editor shows transparency by a special pattern, e. g. a checkerboard pattern. One color entry in a single GIF or PNG images palette can be defined as transparent rather than an actual color, the transparent color should be chosen carefully, to avoid items that just happen to be the same color vanishing. Even this limited form of transparency has patchy implementation, though most popular web browsers are capable of displaying transparent GIF images and this support often does not extend to printing, especially to printing devices which do not include support for transparency in the device or driver. Outside the world of web browsers, support is fairly hit-or-miss for transparent GIF files, however, with, for example, a red background the intermediate colors would be dark red. Gray edge pixels would give an ugly and unclear result, for a variable background color there are no suitable fixed intermediate colors. PNG and TIFF also allows partial transparency, which solves the edge limitation problem, however, support is even more patchy. Internet Explorer prior to version 7 does not support partial transparency in a PNG graphic, very few applications correctly process TIFF files with alpha channels. A major use of transparency, but not the only one, is to produce soft edges in graphics so that they blend into their background. See also monochrome or with shades of gray and anti-aliasing, the process of combining a partially transparent color with its background is often ill-defined and the results may not be exactly the same in all cases. For example, where color correction is in use, should the colors be composited before or after color correction, an alternative approach to full transparency is to use a Clipping path. A clipping path is simply a shape or outline, that is used in conjunction with the other graphics, everything inside the path is visible, and everything outside the path is invisible. The path is inherently vector, but can potentially be used to mask both vector and bitmap data, the main usage of clipping paths is in PostScript files
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Refraction
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Refraction is the change in direction of wave propagation due to a change in its transmission medium. The phenomenon is explained by the conservation of energy and the conservation of momentum, due to the change of medium, the phase velocity of the wave is changed but its frequency remains constant. This is most commonly observed when a wave passes from one medium to another at any other than 0° from the normal. In optics, refraction is a phenomenon that occurs when waves travel from a medium with a given refractive index to a medium with another at an oblique angle. At the boundary between the media, the phase velocity is altered, usually causing a change in direction. Its wavelength increases or decreases, but its frequency remains constant, for example, a light ray will refract as it enters and leaves glass, assuming there is a change in refractive index. A ray traveling along the normal will change speed, but not direction, refraction still occurs in this case. Understanding of this led to the invention of lenses and the refracting telescope. Refraction can be seen looking into a bowl of water. Air has a index of about 1.0003. If a person looks at an object, such as a pencil or straw, which is placed at a slant, partially in the water. This is due to the bending of light rays as they move from the water to the air, once the rays reach the eye, the eye traces them back as straight lines. The lines of sight intersect at a position than where the actual rays originated. This causes the pencil to appear higher and the water to appear shallower than it really is, the depth that the water appears to be when viewed from above is known as the apparent depth. This is an important consideration for spearfishing from the surface because it will make the fish appear to be in a different place. Conversely, an object above the water has a higher apparent height when viewed from below the water, the opposite correction must be made by an archer fish. For small angles of incidence, the ratio of apparent to real depth is the ratio of the indexes of air to that of water. But, as the angle of incidence approaches 90o, the apparent depth approaches zero, albeit reflection increases, the diagram on the right shows an example of refraction in water waves
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Diffraction
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Diffraction refers to various phenomena that occur when a wave encounters an obstacle or a slit. It is defined as the bending of light around the corners of an obstacle or aperture into the region of shadow of the obstacle. In classical physics, the phenomenon is described as the interference of waves according to the Huygens–Fresnel principle. These characteristic behaviors are exhibited when a wave encounters an obstacle or a slit that is comparable in size to its wavelength. Similar effects occur when a wave travels through a medium with a varying refractive index. Diffraction occurs with all waves, including sound waves, water waves, since physical objects have wave-like properties, diffraction also occurs with matter and can be studied according to the principles of quantum mechanics. Italian scientist Francesco Maria Grimaldi coined the word diffraction and was the first to record observations of the phenomenon in 1660. If the obstructing object provides multiple, closely spaced openings, a pattern of varying intensity can result. This is due to the addition, or interference, of different parts of a wave that travel to the observer by different paths, the formalism of diffraction can also describe the way in which waves of finite extent propagate in free space. For example, the profile of a laser beam, the beam shape of a radar antenna. The effects of diffraction are often seen in everyday life and this principle can be extended to engineer a grating with a structure such that it will produce any diffraction pattern desired, the hologram on a credit card is an example. Diffraction in the atmosphere by small particles can cause a ring to be visible around a bright light source like the sun or the moon. A shadow of an object, using light from a compact source. The speckle pattern which is observed when laser light falls on a rough surface is also a diffraction phenomenon. When deli meat appears to be iridescent, that is diffraction off the meat fibers, all these effects are a consequence of the fact that light propagates as a wave. Diffraction can occur with any kind of wave, ocean waves diffract around jetties and other obstacles. Sound waves can diffract around objects, which is why one can hear someone calling even when hiding behind a tree. Diffraction can also be a concern in some applications, it sets a fundamental limit to the resolution of a camera, telescope
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Global illumination
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Global illumination, or indirect illumination, is a general name for a group of algorithms used in 3D computer graphics that are meant to add more realistic lighting to 3D scenes. Theoretically, reflections, refractions, and shadows are all examples of illumination, because when simulating them. In practice, however, only the simulation of diffuse inter-reflection or caustics is called global illumination, images rendered using global illumination algorithms often appear more photorealistic than those using only direct illumination algorithms. However, such images are more expensive and consequently much slower to generate. One common approach is to compute the global illumination of a scene, the stored data can then be used to generate images from different viewpoints for generating walkthroughs of a scene without having to go through expensive lighting calculations repeatedly. Though this method of approximation is easy to perform computationally, when used alone it does not provide a realistic effect. Ambient lighting is known to flatten shadows in 3D scenes, making the visual effect more bland. However, used properly, ambient lighting can be an efficient way to make up for a lack of processing power, more and more specialized algorithms are used in 3D programs that can effectively simulate the global illumination. These algorithms are numerical approximations to the rendering equation, well known algorithms for computing global illumination include path tracing, photon mapping and radiosity. A full treatment can be found in Another way to simulate real global illumination is the use of High dynamic range images, also known as environment maps and this process is known as image-based lighting. Theory and practical implementation of Global Illumination using Monte Carlo Path Tracing
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Caustic (optics)
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In optics, a caustic or caustic network is the envelope of light rays reflected or refracted by a curved surface or object, or the projection of that envelope of rays on another surface. The caustic is a curve or surface to each of the light rays is tangent. Therefore, in the adjacent image, the caustics can be the patches of light or their bright edges and these shapes often have cusp singularities. Concentration of light, especially sunlight, can burn, the word caustic, in fact, comes from the Greek καυστός, burnt, via the Latin causticus, burning. A common situation where caustics are visible is when light shines on a drinking glass, the glass casts a shadow, but also produces a curved region of bright light. In ideal circumstances, a patch of light can be produced. Rippling caustics are commonly formed when light shines through waves on a body of water, another familiar caustic is the rainbow. Scattering of light by raindrops causes different wavelengths of light to be refracted into arcs of differing radius, in computer graphics, most modern rendering systems support caustics. Some of them even support volumetric caustics and this is accomplished by raytracing the possible paths of a light beam, accounting for the refraction and reflection. Photon mapping is one implementation of this, volumetric caustics can also be achieved by volumetric path tracing. Some computer graphic systems work by forward ray tracing wherein photons are modeled as coming from a light source, Caustics are formed in the regions where sufficient photons strike a surface causing it to be brighter than the average area in the scene. “Backward ray tracing” works in the reverse manner beginning at the surface, some examples of 3D ray-traced caustics can be found here. The focus of most computer systems is aesthetics rather than physical accuracy. This is especially true when it comes to real-time graphics in games where generic pre-calculated textures are mostly used instead of physically correct calculations. Researchers have found that they can make use of caustics to create an image by shaping transparent material in a particular way. Focus Circle of confusion Caustic Born, Max, Wolf, Emil, principles of Optics, Electromagnetic Theory of Propagation, Interference and Diffraction of Light. Natural Focusing and Fine Structure of Light, Caustics and Wave Dislocations, real-time volume caustics with adaptive beam tracing. Symposium on Interactive 3D Graphics and Games
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Depth of field
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In some cases, it may be desirable to have the entire image sharp, and a large DOF is appropriate. In other cases, a small DOF may be more effective, in cinematography, a large DOF is often called deep focus, and a small DOF is often called shallow focus. Precise focus is possible at one distance, at that distance. At any other distance, a point object is defocused, and will produce a blur spot shaped like the aperture, when this circular spot is sufficiently small, it is indistinguishable from a point, and appears to be in focus, it is rendered as acceptably sharp. The acceptable circle of confusion is influenced by visual acuity, viewing conditions, the increase of the circle diameter with defocus is gradual, so the limits of depth of field are not hard boundaries between sharp and unsharp. For 35 mm motion pictures, the area on the film is roughly 22 mm by 16 mm. The limit of tolerable error was traditionally set at 0.05 mm diameter, while for 16 mm film, where the size is half as large. More modern practice for 35 mm productions set the circle of confusion limit at 0.025 mm, for full-frame 35mm still photography, the circle of confusion is usually chosen to be about 1/30 mm. Many sources propose CoC limits as a fraction of the film format diagonal, the three formats above at fraction 1/1500 would use 0.029,0.056, and 0.017 mm. Traditional depth-of-field formulas and tables assume equal circles of confusion for near and far objects, the loss of detail in distant objects may be particularly noticeable with extreme enlargements. Achieving this additional sharpness in distant objects usually requires focusing beyond the hyperfocal distance, with this approach, foreground objects cannot always be made perfectly sharp, but the loss of sharpness in near objects may be acceptable if recognizability of distant objects is paramount. Other authors have taken the position, maintaining that slight unsharpness in foreground objects is usually more disturbing than slight unsharpness in distant parts of a scene. The combination of length, subject distance, and format size defines magnification at the film / sensor plane. DOF is determined by subject magnification at the film / sensor plane, for a given f-number, increasing the magnification, either by moving closer to the subject or using a lens of greater focal length, decreases the DOF, decreasing magnification increases DOF. For a given magnification, increasing the f-number increases the DOF. If the original image is enlarged to make the final image, when focus is set to the hyperfocal distance, the DOF extends from half the hyperfocal distance to infinity, and the DOF is the largest possible for a given f-number. The comparative DOFs of two different format sizes depend on the conditions of the comparison, the DOF for the smaller format can be either more than or less than that for the larger format. In the discussion that follows, it is assumed that the images from both formats are the same size, are viewed from the same distance, and are judged with the same circle of confusion criterion
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Motion blur
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Motion blur is the apparent streaking of rapidly moving objects in a still image or a sequence of images such as a movie or animation. It results when the image being recorded changes during the recording of a single exposure, when a camera creates an image, that image does not represent a single instant of time. Because of technological constraints or artistic requirements, the image may represent the scene over a period of time, in such an image, any object moving with respect to the camera will look blurred or smeared along the direction of relative motion. This smearing may occur on an object that is moving or on a static background if the camera is moving, in a film or television image, this looks natural because the human eye behaves in much the same way. Because the effect is caused by the motion between the camera, and the objects and scene, motion blur may be avoided by panning the camera to track those moving objects. In this case, even with long exposure times, the objects will appear sharper, in computer animation this effect must be simulated as a virtual camera actually does capture a discrete moment in time. This simulated motion blur is typically applied when either the camera or objects in the scene move rapidly, without this simulated effect each frame shows a perfect instant in time, with zero motion blur. This is why a game with a frame rate of 25-30 frames per second will seem staggered. Many modern video games feature motion blur, especially vehicle simulation games, some of the better-known games that utilise this are the recent Need for Speed titles, Unreal Tournament III, The Legend of Zelda, Majoras Mask, among many others. In pre-rendered computer animation, such as CGI movies, realistic motion blur can be drawn because the renderer has more time to each frame. Temporal anti-aliasing produces frames as a composite of many instants, frames are not points in time, they are periods of time. Most computer animations systems make the classic fence-post error in the way they handle time, thus most computer animation systems will incorrectly place an object on a four frame trip along a path at 0%,0. 33%,0. 66%, and 1. Motion lines in cel animation are drawn in the direction as motion blur. Go motion is a variant of stop motion animation that moves the models during the exposure to create a less staggered effect, in 2D computer graphics, motion blur is an artistic filter that converts the digital image/bitmap/raster image in order to simulate the effect. Many graphical software products offer simple motion blur filters, however, for advanced motion blur filtering including curves or non-uniform speed adjustment, specialized software products are necessary. When an animals eye is in motion, the image will suffer from motion blur, to cope with this, humans generally alternate between saccades and fixation. Saccadic masking makes motion blur during a saccade invisible, similarly, smooth pursuit allows the eye to track a target in rapid motion, eliminating motion blur of that target instead of the scene. Although this gives sharper slow motion replays it can look strange at normal speed because the eye expects to see motion blurring and is not provided with blurred images, conversely, extra motion blur can unavoidably occur on displays when it is not desired
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Image tracing
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In computer graphics, image tracing, raster-to-vector conversion or vectorization is the conversion of raster graphics into vector graphics. An image does not have any structure, it is just a collection of marks on paper, grains in film, while such an image is useful, it has some limits. If the image is magnified enough, its artifacts appear, the halftone dots, film grains and pixels become apparent. Images of sharp edges become fuzzy or jagged, ideally, a vector image does not have the same problem. Edges are represented as a mathematical lines or curves, and they can be magnified thousands of times — until the precision of the numbers becomes an issue, the task in vectorization is to convert a two-dimensional image into a two-dimensional vector representation of the image. It is not examining the image and attempting to recognize or extract a three-dimensional model which may be depicted, for most applications, vectorization also does not involve optical character recognition, characters are treated as lines, curves, or filled objects without attaching any significance to them. In vectorization the shape of the character is preserved, so artistic embellishments remain, synthetic images such as maps, cartoons, logos, clip art, and technical drawings are suitable for vectorization. Those images could have been made as vector images because they are based on geometric shapes or drawn with simple curves. Continuous tone photographs are not good candidates for vectorization, the input to vectorization is an image, but an image may come in many forms such as a photograph, a drawing on paper, or one of several raster file formats. Programs that do raster-to-vector conversion may accept bitmap formats such as TIFF, BMP, the output is a vector file format. Common vector formats are SVG, DXF, EPS, EMF, vectorization can be used to update images or recover work. Personal computers often come with a paint program that produces a bitmap output file. These programs allow users to make simple illustrations by adding text, drawing outlines, only the results of these operations are saved in the resulting bitmap, the drawing and filling operations are discarded. Vectorization can be used to some of the information that was lost. Vectorization is also used to recover information that was originally in a vector format but has been lost or has become unavailable, a company may have commissioned a logo from a graphic arts firm. Although the graphics used a vector format, the client company may not have received a copy of that format. The company may then acquire a vector format by scanning and vectorizing a paper copy of the logo, the image can be vectorized manually. A person could look at the image, make some measurements and that was the case for the vectorization of a technical illustration about neutrinos
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