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Dilution Of Precision (computer Graphics)
Dilution of precision is an algorithmic trick used to handle difficult problems in hidden-line removal, caused when horizontal and vertical edges lie on top of each other due to numerical instability. Numerically, the severity escalates when a CAD model is viewed along the principal axis or when a geometric form is viewed end-on. The trick is to alter the view vector by a small amount, thereby hiding the flaws. Unfortunately, this mathematical modification introduces new issues of its own, namely that the exact nature of the original problem has been destroyed, and visible artifacts of this kludge A kludge or kluge () is a workaround or quick-and-dirty solution that is clumsy, inelegant, inefficient, difficult to extend and hard to maintain. This term is used in diverse fields such as computer science, aerospace engineering, Internet sla ... will continue to haunt the algorithm. One such issue is that edges that were well defined and hidden will now be problematic. Another commo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Algorithm
In mathematics and computer science, an algorithm () is a finite sequence of rigorous instructions, typically used to solve a class of specific Computational problem, problems or to perform a computation. Algorithms are used as specifications for performing calculations and data processing. More advanced algorithms can perform automated deductions (referred to as automated reasoning) and use mathematical and logical tests to divert the code execution through various routes (referred to as automated decision-making). Using human characteristics as descriptors of machines in metaphorical ways was already practiced by Alan Turing with terms such as "memory", "search" and "stimulus". In contrast, a Heuristic (computer science), heuristic is an approach to problem solving that may not be fully specified or may not guarantee correct or optimal results, especially in problem domains where there is no well-defined correct or optimal result. As an effective method, an algorithm ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hidden-line Removal
In 3D computer graphics, solid objects are usually modeled by polyhedra. A face of a polyhedron is a planar polygon bounded by straight line segments, called edges. Curved surfaces are usually approximated by a polygon mesh. Computer programs for line drawings of opaque objects must be able to decide which edges or which parts of the edges are hidden by an object itself or by other objects, so that those edges can be clipped during rendering. This problem is known as hidden-line removal. The first known solution to the hidden-line problem was devised by L. G. Roberts in 1963. However, it severely restricts the model: it requires that all objects be convex. Ruth A. Weiss of Bell Labs documented her 1964 solution to this problem in a 1965 paper. In 1966 Ivan E. Sutherland listed 10 unsolved problems in computer graphics. Problem number seven was ''"hidden-line removal"''. In terms of computational complexity, this problem was solved by Devai in 1986.F. Devai. Quadratic boun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numerical Instability
In the mathematics, mathematical subfield of numerical analysis, numerical stability is a generally desirable property of numerical algorithms. The precise definition of stability depends on the context. One is numerical linear algebra and the other is algorithms for solving ordinary and partial differential equations by discrete approximation. In numerical linear algebra, the principal concern is instabilities caused by proximity to singularities of various kinds, such as very small or nearly colliding eigenvalues. On the other hand, in numerical algorithms for differential equations the concern is the growth of round-off errors and/or small fluctuations in initial data which might cause a large deviation of final answer from the exact solution. Some numerical algorithms may damp out the small fluctuations (errors) in the input data; others might magnify such errors. Calculations that can be proven not to magnify approximation errors are called ''numerically stable''. One of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CAD Model
Computer-aided design (CAD) is the use of computers (or ) to aid in the creation, modification, analysis, or optimization of a design. This software is used to increase the productivity of the designer, improve the quality of design, improve communications through documentation, and to create a database for manufacturing. Designs made through CAD software are helpful in protecting products and inventions when used in patent applications. CAD output is often in the form of electronic files for print, machining, or other manufacturing operations. The terms computer-aided drafting (CAD) and computer aided design and drafting (CADD) are also used. Its use in designing electronic systems is known as ''electronic design automation'' (''EDA''). In mechanical design it is known as ''mechanical design automation'' (''MDA''), which includes the process of creating a technical drawing with the use of computer software. CAD software for mechanical design uses either vector-based graphics t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
View Vector
This is a glossary of terms relating to computer graphics. For more general computer hardware terms, see glossary of computer hardware terms This glossary of computer hardware terms is a list of definitions of terms and concepts related to computer hardware, i.e. the physical and structural components of computers, architectural issues, and peripheral devices. A .... 0–9 A B C D E F G H I K L M N O P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kludge
A kludge or kluge () is a workaround or quick-and-dirty solution that is clumsy, inelegant, inefficient, difficult to extend and hard to maintain. This term is used in diverse fields such as computer science, aerospace engineering, Internet slang, evolutionary neuroscience, and government. It is similar in meaning to the naval term ''jury rig''. Etymology The word has alternate spellings (''Wikt:kludge, kludge'' and ''Wikt:kluge, kluge''), pronunciations ( and , rhyming with ''judge'' and ''stooge'', respectively), and several proposed etymologies. Jackson W. Granholm The ''Oxford English Dictionary'' (2nd ed., 1989), cites Jackson W. Granholm's 1962 "How to Design a Kludge" article in the American computer magazine ''Datamation''. kludge Also kluge. [J. W. Granholm's jocular invention: see first quot.; cf. also ''bodge'' v., ''fudge'' v.]'An ill-assorted collection of poorly-matching parts, forming a distressing whole' (Granholm); esp. in ''Computing'', a machine, system, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
