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ABSTRACT: Performance evaluation techniques for fundamental graphics algorithms and for algorithms to be used in multimedia and embedded systems are investigated. Models of computation considering only arithmetic and logic operations taken on input data are regarded as inadequate for processors with instruction-level parallelism. For experimental evaluation of graphics algorithms clock-cycle counting is found more accurate than elapsed-time functions provided by system software. Some difficulties and anomalies with clock-cycle counting on Pentium processors are also reported. An evaluation technique based on best sustained performance is proposed. The paper concludes that it may not even be possible to tell the exact number of clock cycles taken by operations of processors based on asynchronous circuits.
Geometric Modeling and Imaging, 2008. GMAI 2008. 3rd International Conference on; 08/2008
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ABSTRACT: The potential and the limitations of the Java language for graphics and visualisation research are evaluated. Evidence is offered that Java is adequate for high-performance computing and still has the added benefit of the portability of its compiled byte code over a wide range of platforms. It is demonstrated that, contrary to popular belief, there is an efficient way for reading and writing individual pixels. It is also demonstrated that graphics primitives can be drawn in one memory access per pixel even without pointer arithmetics. Just-in-time and hot-spot compiler technologies considerably improve the speed of the executable code, though some penalty remains for dynamic binding. Some inconsistencies and flaws in the design and implementations of the Java class libraries are noted. In general, however, Java offers both portability and adequate performance of the executable code, and also increased productivity due to its extensive class libraries, therefore it should be a serious consideration for researchers, developers and educators in graphics and visualisation.
Information Visualisation, 2002. Proceedings. Sixth International Conference on; 02/2002
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F. Devai
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ABSTRACT: A mathematical model for the expected-time analysis of
line-clipping algorithms is proposed. Assuming that all clipping windows
are equally likely, we demonstrate that the probability of a line
segment being totally outside the window approaches the value of 8/9,
provided that the line segments tend to be short and evenly distributed
within a rectangle. Acceptance-rejection matrices are introduced for a
machine-independent comparison of algorithms. A new line-clipping
method, called QuickClip, is also proposed. QuickClip is not only
simpler and more concise than the Cohen-Sutherland algorithm, the most
widely used method in computer graphics, but also faster both in terms
of machine-independent analysis and timing results on random line
segments. Timing results also indicate that QuickClip is significantly
faster than the Nicholl-Lee-Nicholl (1987) algorithm. The theoretical
results generalise to 3D, with the important consequence that the
average clipping volume is 1/27 of the volume of the model
Information Visualization, 1998. Proceedings. 1998 IEEE Conference on; 08/1998
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ABSTRACT: The computer-graphics aspects of the visualization of large data sets, in particular, digital models of real or planned solid objects in a heterogeneous distributed environment are investigated. It is demonstrated that binary-swap compositing does not scale well on networks of workstations. A multi-server system, based on scanline algorithms and using Java technology, is proposed. The proposed system is efficient as servers only need to solve a problem of growth rate of n log n, it is fault tolerant as both lost messages and server failures are tolerated, and it has negligible hardware costs as it runs on existing networks of workstations. The system is also scalable, as data sets are sent to all servers in the same packets, regardless of the number of servers, and the amount of data sent back by servers only depends on the resolution of the final image
Geometric Modeling and Imaging--New Trends, 2006; 09/1993
