  The vector map layers data, provided there, originated from Vector Smart Map Level 0 
database published by National Imagery and Mapping Agency (NIMA) in form of shape-files. 
The content of the database is similar to the previously published Digital Chart of 
the World (DCW), augmented with low-resolution bathymetry for global coverage.
  Only limited set of layers presented here, related to water resources of Earth. 
The datum presented here generally in form of .VML-files (stands Vector Map Layer), 
which is proprietary compressed format of author of the datum. Layers of the datum 
additionally augmented with Level Of Details (LOD) attribute "_LOD" for optimized 
appearance through using in LOD-policy feature of Spatial Aspect Explorer software 
product of author. Also the data was undergoing vector quantization filtering with 
following representation to set of respective VML-files of different resolutions for 
additional optimization of speed and appearance, and also was undergoing 
splitting per original tiles for same purposes.
  Additionally the datum contains data for Antarctica, re-projected to Polar 
Stereographic projection.


See site of author: www.runspect.com for more details.
Copyright (c) 2011-2016 Yuri Feldman
