Vector Map
Vector Map ( VMAP ) is a worldwide vector -based topographic- cartographic information system of NATO, which is published by the NGA, the military - geographic authority of the United States.
The card is available in different levels of accuracy:
- VMAP Level 0 is based on the Operational Navigation Chart ( ONC ) at a scale of 1:1,000,000 and is freely available,
- VMAP Level 1 is based on the scale of 1:250,000 and is reserved to a large extent for military purposes.
Reference systems and accuracy
- Horizontal datum is WGS84, with an accuracy of between about 2000 and 4000 meters
- Vertical datum is Mean Sea Level (MSL, height above sea level), accuracy between 150 ( contour lines ) and 30 meters ( highlights )
Spatial classification
The VMAP - 0 data are divided into four regions ( North America, South America and Africa, Europe and northern Asia, Southeast Asia and Australia). Each data packet is zipped around 200 MB in size. The VMAP -1 data are divided into 234 zones, of which 57 zones freely available.
Thematic outline
The VMAP is divided into different topics ( coverages ), which in turn contain sub-categories:
- Political entities ( political units)
- Place Names ( place names )
- Boundaries ( boundaries )
- Data Quality ( Data Quality )
- Elevation ( altitude )
- Hydrography ( Hydrographic )
- Industry (Industry)
- Physiography ( morphology of Earth's surface )
- Population ( population)
- Transportation (transportation)
- Utilities ( utilities )
- Vegetation ( vegetation)
Data format
The VMAP is stored in the Vector Product Format ( VPF ), a division into directories and binary files. The VPF is described in military standard MIL -STD- 2407.
Documentation
The VMAP detailed description is documented in the specification MIL -PRF- 89039, supplemented by the second supplemental agreement dated June 27, 2001