A Computationally Efficient Technique for the Improvement of the Display of Geospatial Information Stored in Geographic Coordinates
Abstract
Geographical Information Systems (GIS) frequently store positional information in geographic coordinates (i.e., degrees of latitude and longitude). As a result, when GIS data are displayed on a video terminal, it is a usual practice to display the information "un-projected" with the view window x and y axis scaled in decimal degrees with degrees of longitude and latitude having the same scale factor on each axis. While this practice results in fast display time, avoiding the computational load imposed by complex cartographic projections, it results in a display that distorts the spatial relationships of the elements displayed on screen unless the displayed area is near the equator. A simple method is proposed as an alternative that greatly improves the display "fidelity" without adding any significant additional computational load. (6 figures, 3 refs.)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 11, 2003
- Accession Number
- ADA416769
Entities
People
- Frank P. Mccreedy
- Hillary C. Mesick
- Michael M. Harris
Organizations
- United States Naval Research Laboratory