Spherical Mapping Corrector

This filter produces texture map correction for spherical texture mapping. Special thanks to Paul Bourke for allowing his Algorithm to be ported to this plugin.DESCRIPTION:This filter produces texture map correction for spherical mapping.When projecting a rectangular texture onto a Sphere using traditional spherical mapping coordinates, distortion (`pinching`) occurs at the poles where the texture must come to a point. Given the different topology of a plane and a sphere, it is impossible to avoid this, or any kind of distortion. However, by properly distorting the texture map, it is possible to minimize and even compensate for the polar distortion.Special thanks to Paul Bourke for allowing his algorithm to be ported to this plugin. For more information, please Visit Mr. Bourke`s site at http://astronomy.swin.edu.au/~pbourke/.Sub-Sampling: Specifies what type of pixel sub-sampling to use. (Nearest Neighbor being fastest, Bicubic being best.