Vector map

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Vector Map ( VMAP ) is a worldwide vector- based topographic- cartographic information system of NATO , which is published by the NGA , the military-geographical authority of the USA.

The map is available in different levels of accuracy:

  • VMAP Level 0 is based on the Operational Navigation Chart (ONC) on a scale of 1: 1,000,000 and is freely available,
  • VMAP Level 1 is based on the scale 1: 250,000 and is largely reserved for military purposes.

Frames and Accuracy

  • The horizontal datum is WGS84 , with an accuracy between approximately 2000 and 4000 meters
  • The vertical date is Mean Sea Level (MSL, height above sea level ), accuracy between 150 ( contour lines ) and 30 meters (height points)

Spatial structure

The VMAP-0 data is divided into four areas (North America, South America and Africa, Europe and northern Asia, Southeast Asia and Australia). Each data package is zipped a good 200 MB. The VMAP-1 data are divided into 234 zones, 57 of which are freely available.

Thematic structure

The VMAP is divided into various topics (coverages), which in turn contain sub-categories:

  • Political Entities
  • Place Names
  • Boundaries
  • Data quality
  • Elevation (height information)
  • Hydrography ( hydrography )
  • Industry
  • Physiography ( morphology of the earth's surface)
  • Population
  • Transportation
  • Utilities
  • Vegetation (vegetation)

Data format

The VMAP is stored in the Vector Product Format (VPF), which is divided into directories and binary files. The VPF is described in the military standard MIL-STD-2407.

documentation

The detailed VMAP description is documented in specification MIL-PRF-89039, supplemented by the second amendment of June 27, 2001

Web links