Hidden surface removal can be achieved using the priority face determination (PFD) tree to create a priority ordering of n polygons in log(4/3) n time. In this paper, we show how the number of polygons stored in the t...
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Hidden surface removal can be achieved using the priority face determination (PFD) tree to create a priority ordering of n polygons in log(4/3) n time. In this paper, we show how the number of polygons stored in the tree and drawn to the screen can be minimized significantly by determining, at the pre-processing stage, which polygons are completely hidden by other polygons from particular regions of the scene. The removal of hidden polygons at the pre-processing stage means that there is no need to even consider them at run time. The cost for the resulting decrease in run time is an increase in the pre-processing time, but techniques for reducing this are presented. (C) 1999 Elsevier Science Ltd. All rights reserved.
We present a method for the hierarchical representation of vector fields. Our approach is based on iterative refinement using clustering and principal component analysis. The input to our algorithm is a discrete set o...
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ISBN:
(纸本)9780780358973
We present a method for the hierarchical representation of vector fields. Our approach is based on iterative refinement using clustering and principal component analysis. The input to our algorithm is a discrete set of points with associated vectors. The algorithm generates a top-down segmentation of the discrete field by splitting clusters of points. We measure the error of the various approximation levels by measuring the discrepancy between streamlines generated by the original discrete field and its approximations based on much smaller discrete data sets. Our method assumes no particular structure of the field, nor does it require any topological connectivity information. It is possible to generate multiresolution representations of vector fields using this approach.
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