Research Visibility maps and spherical algorithms
نویسنده
چکیده
By the extraction of ideas from computer vision, geometrical design and complexity analysis, a structure called visibility emerges. The paper describes a way in which a 3D workpiece is mapped onto the unit sphere, and its visibility is determined. For applications, manufacturing machines are classified by their degrees of freedom into point, line and surface visible processes. Algorithms for optimal workpiece orientation are then formulated as simple intersections on the sphere.
منابع مشابه
Performance Evaluation of Detector Algorithms of Dust Storms in Arid Lands (Case Study: Yazd Province)
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متن کاملComputing global visibility maps for regions on the boundaries of polyhedra using Minkowski sums
A global visibility map is a spherical image built to describe the complete set of global visible view directions for a surface. In this paper, we consider the computation of global visibility maps for regions on the boundary of a polyhedron. Both the self-occlusions introduced by a region and the global occlusions introduced by the rest of the surfaces on the boundary of the polyhedron are con...
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In the Any-Angle Pathfinding problem, the goal is to find the shortest path between a pair of vertices on a uniform square grid, that is not constrained to any fixed number of possible directions over the grid. Visibility Graphs are a known optimal algorithm for solving the problem with the use of preprocessing. However, Visibility Graphs are known to perform poorly in terms of running time, es...
متن کاملParallel and adaptive visibility sampling for rendering dynamic scenes with spatially varying reflectance
Fast rendering of dynamic scenes with natural illumination, all-frequency shadows and spatially-varying reflections is important but challenging. One main difficulty brought by moving objects is that the runtime visibility update of dynamic occlusion is usually time-consuming and slow. In this paper, we present a new visibility sampling technique and show that efficient all-frequency rendering ...
متن کاملEfficient From-Point Visibility for Global Illumination in Virtual Scenes with Participating Media
Visibility determination is one of the fundamental building blocks of photorealistic image synthesis. Light reflected at a shading point depends on light reflected from the visible scene surfaces and on the visible light sources in the environment. However, computing visibility is computational highly demanding and global illumination algorithms, such as final gathering and bias compensation fo...
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