Date Available
12-7-2011
Year of Publication
2001
Document Type
Thesis
College
Engineering
Department
Computer Science
First Advisor
Frank Cheng
Abstract
The initial attempt was to find efficient technique to identify shadow plylgons in the shadow-volume based shadow generation algorithm. It was observed that shadows correspond to loops of ridge edges (REs). By identifying all the non-overlapping RE loops of a 3D object, one finds all the shadow polygons and, consequently, all the shadows it generates on other objects as well as shadows it generates on itself. This, however, requires extensive edge-edge intersection tests.It was subsequently realized that by storing the angular representations of the RE looks in a look up table, one can avoid the need of decomposing RE loops into non-overlapping loops and, consequently, the need of performation extensive edge-edge intersection tests. Actually, by building the look up table in a way similar to the bucket-sorted edge table of the standard scan-line method, one can use the table in the scan conversion process to mark the pixels that are in shadow directly, without the need of performing any ray-polygon intersection tests as required in the shadow-volume based shadow generation algorithm. Hence, one gets a new shadow generation technique without the need of performing expensive tests.
Recommended Citation
Thakur, Khageshwar, "Shadow generation Based on RE loops and their angular representations" (2001). University of Kentucky Master's Theses. 219.
https://uknowledge.uky.edu/gradschool_theses/219
