GéoServices ICDG

Introduction

The NTS Lookup Service is a web service which returns geometries for known NTS mapsheet identifiers or by latitude/longitude coordinates, at scales of 50 000, 250 000 and 1 000 000. This service sits atop algorithms developed by the Centre for Topographic Information Sherbrooke (CTIS).

The Service returns record(s) for matching placenames with geometry, encoded in GML3.00.

National Topographic System

Topographic maps produced by Natural Resources Canada conform to the National Topographic System (NTS) of Canada. The National Topographic System provides general-purpose topographic map coverage of the entire Canadian landmass. These maps depict, in detail, ground relief, drainage, forest cover, administrative areas, populated areas, transportation routes and facilities, and cultural features. They are available in two standard scales, 1:50 000 and 1:250 000, as well as a 1:1 000 000. The maps show a geographic grid (longitude and latitude) and a Universal Transverse Mercator (UTM) grid (kilometres). The area covered by a given map sheet is determined by its latitude and longitude. Since the National Topographic System uses a standard numbering system, knowing the map number allows you to quickly identify adjacent map sheets.

Please see http://maps.nrcan.gc.ca/maps101/nts.html for more details.

Operations

The CGDI NTS Lookup Service accepts both HTTP GET and HTTP POST. Keyword parameters and values are case insensitive. If the version parameter is omitted for any operation, the service will invoke the most current version of the service.

The service supports two operations:

• GetCapabilities
• GetMapsheet

GetCapabilities

The purpose of the GetCapabilities operation is to provide general information about the service itself and specific information about the name sources used. Please visit the example page to view the response format.

Request parameter	Required/Optional	Description
VERSION=x.y.z	O	Request version
REQUEST=GetCapabilities	R	Request name

GetCapabilities

The purpose of GetMapsheet is to return the geometries for an NTS mapsheet inputted by a request. The UML model of the reposnse format is shown below: Please visit the example page to view the response format.

Request parameter	Required/Optional	Description
VERSION=x.y.z	O	Request version
REQUEST=GetMapsheet	R	Request name
MAPSHEET=mapsheet	R	Mapsheet code
LAT=latitude	R	Point latitude in degrees
LON=longitude	R	Point longitude in degrees
SCALE=50000|250000|1000000	R	Map scale
Either the mapsheet index OR the latitude/longitude/scale must be supplied; the mapsheet index value will take precendence over point coordinates
NEATLINE=interval	O	Point interval to create the neatline geometry, expressed in minutes.

Web Services Description Language (WSDL)

The NTS Lookup Service also provides WSDL bindings, allowing WSDL aware clients to generate request operations in accordance with service definitions. The WSDL document is at: http://geoservices.cgdi.ca/NTS/NTSLookup?wsdl

A printable version of this document is available

Revision History

updated: 26-June-2003