Topographic maps are based on topographical surveys. Performed at large scales, these surveys are called topographical in the old sense of topography, showing a variety of elevations and landforms. This is in contrast to older cadastral surveys, which primarily show property and governmental boundaries. The first multi-sheet topographic map series of an entire country, the Carte géométrique de la France, was completed in 1789. The Great Trigonometric Survey of India, started by the East India Company in 1802, then taken over by the British Raj after 1857 was notable as a successful effort on a larger scale and for accurately determining heights of Himalayan peaks from viewpoints over one hundred miles distant.
Global indexing system first developed for International Map of the World
Topographic surveys were prepared by the military to assist in planning for battle and for defensive emplacements (thus the name and history of the United Kingdom's Ordnance Survey). As such, elevation information was of vital importance.
As they evolved, topographic map series became a national resource in modern nations in planning infrastructure and resource exploitation. In the United States, the national map-making function which had been shared by both the Army Corps of Engineers and the Department of the Interior migrated to the newly created United States Geological Survey in 1879, where it has remained since.
1913 saw the beginning of the International Map of the World initiative endeavoring to map all of Earth's significant land areas at 1:1 million scale on about one thousand sheets covering four degrees latitude by six or more degrees longitude. Excluding boundaries, each sheet was 44 cm high and (depending on latitude) up to 66 cm wide. Although the project eventually foundered, it left an indexing system that remains in use.
By the 1980s, centralized printing of standardized topographic maps began to be eroded by databases of coordinates that could be used on computers by moderately skilled end users to view or print maps with arbitrary contents, coverage and scale. For example the Federal government of the United States' TIGER initiative compiled interlinked databases of federal, state and local political borders and census enumeration areas, and of roadways, railroads, and water features with support for locating street addresses within street segments. TIGER was developed in the 1980s and used in the 1990 and subsequent decennial censuses. Digital elevation models (DEM) were also compiled, initially from topographic maps and stereographic interpretation of aerial photographs and then from satellite photography and radar data. Since all these were government projects funded with taxes and not classified for national security reasons, the datasets were in the public domain and freely usable without fees or licensing.
Posted by Jorg Mohnen |
On 30 Jan 2015 |
Updated on 01 Feb 2015 |
Since we started selling WavGen Pro software with our Authorize.NET partnership and Bank of America Merchant system back in 2003, we proudly annouce the 10,000th online sale made in Portugal today. Its been a wonderful growth process. Since the 1990's where we honed in on 3D Terrain Visualization wortk flows, and since moving to Los Angeles to take part in software development in the VFX and Graphics industries, we now have a full product portfolio including the licensing of massive geospatial imagery.
WavGen Incorporated sells and licenses many different types of satellite data, geodata, p..
We welcome all to our booth number 211 near AutoDesk and ESRi at this years SIGGRAPH 2015 trade show in Los Angeles. We will be demonstrating our WavGen Pro software on 4xHDPS PODs and will be streaming many of our television and large format feature film productions. We will also be demonstrating and licensing our large selection of geospatial data of the earth on planetary systems.
The SIGGRAPH conference and exhibition is a five-day interdisciplinary educational experience including a three-day commercial exhibition that attracts hundreds of exhibitors from around the world. SIGGRA..
EarthOnDrive & WavGen have recently partnered with Battlespace Simulatons Inc., to provide a rich geospatial data environment using 15m Landsat Imagery, and very high resolution CONUS aerial imagery for tactical and ground based military and defense simulations. GIS-enabled: Pan, Scale or Zoom anywhere on Earth. Support for all the most common GIS formats, including NGA's aeronautical charts (GNC, JNC, ONC, TPC) in CADRG format; GeoTiff and Vector formats (VPF and SHP).
BSI provides world-class, PC-based simulation solutions, including MACE, the flagship product providing comp..
Produced by the Environmental Systems Research Institute (Esri, formerly ESRI), the Esri International User Conference (Esri UC) is the worlds largest event dedicated to geographic information system (GIS) technology. The 2015 Esri User Conference (UC) July 20-24 2015 will be held at the San Diego Convention Center in San Diego, California. The Esri UC dates back to 1981. In 2008, conference attendance grew to more than 14,000 attendees.
The conference offers more than 600 GIS user presentation sessions, 300 exhibitors, 275 technical workshops, 100 special interest, regional, and user group..