A GeoSpatial Mapping Architecture

Matthew Blanchette

Graduate Student & Research AssistantComputer Science Department

Research Computer Group & ISIS

University of Southern Maine

GeoPortal Project

Maine GeoLibrary Board

Overview

• System Goals & Layout

• Data Sources

• Open-Source Mapping Servers

• OGC Standards

• Google Visualization

• Visualization Alternative

System Goals

Functionality:• Allow Web Access to Geospatial Data• Display Geospatial Data in a Map Viewer

Implementation:• Flexibility – Swap system components• Cost Minimized

• Open Source & Free Geospatial Tools• Geospatial Web Standards

System Layout

Example Case: ACFISH2 Shapefile DataPoint locations of streams and rivers in Maine with runs and passages of anadromous and catadromous fish.Maine Office of Geographic Information Systems Cataloghttp://megis.maine.gov/catalog/

Data Source - Shapefile

ESRI Geospatial Data FormatCollection of files to describe geometries (points,

polygons, lines) spatially and with attributes

Example case: ACFISH2acfish2.dbf, acfish2.prj, acfish2.shp, acfish2.shxMetadata:acfish2.xml, acfish2.txt., acfish2.htm

Data Source - Database

Spatially Enabled (PostGIS for PostgreSQL, MyGIS for MySQL)

Example case: ACFISH2Attribute columns – ID, NAME, YEAR,…Geometry column – Points

Open Source Mapping Servers

MapServer

University of MinnesotaPhD Project, NASA, 1994

C, CGI, OGR/GDALMapscript

(PHP,Java,Python,etc)

PostGIS, Oracle Spatial, ArcSDE, MySQL, Shapefiles

OGC Standards

GeoServer

The Open Planning Project, Data Sharing - WFS, 2001

Java, GeoTools

PostGIS, Oracle Spatial, ArcSDE, DB2, MySQL, Shapefiles

OGC Standards

OGC Standards

Open Geospatial Consortium – international geospatial standards organization

• WMS: Web Map Service– Specification for providing map images– MapServer and GeoServer

• SLD: Styled Layer Descriptor– XML schema for styling map layers (WMS)

• KML: Keyhole Markup Language– XML schema for geographic visualization and

annotation– Keyhole, Inc. and Google– GeoServer & GeoTools can output as KML

WMS Example

ACFISH2 MapServer WMS Image

KML Example

<Placemark id="acfish2.176"><name>acfish2.176</name><description><![CDATA[<b>ACFISH2_ID</b>: 33<br /><b>DMR_ID</b>: F3<br /><b>ECCM_ID</b>: <br /><b>YEAR</b>: 1982<br /><b>ECCM_SP</b>: <br /><b>USFW_SP</b>: <br /><b>DMR_SP</b>: ADEGHNS<br /><b>DMR_NAME</b>: KENNEBEC

RIVER<br/>]]></description><MultiGeometry><Point><coordinates>-69.78452182688191,43.77204938317024</coordinates></Point></MultiGeometry></Placemark>

ACFISH2 KML• Libraries in many

languages to edit and produce XML

• GeoTools and XMLBeans (Java)

Concerns:• Projection

Transformation• Embedding

Descriptive Information

Google Visualization

Google Maps: free web mapping applicationBrowser, Javascript, APIMaps, Satellite, Terrain, Traffic, Street View

Google Earth: free 3D globe programVariety of OS: Windows, Mac, Linux

Google Earth Plugin: same 3D globe service Browser: Firefox or IE 6/7Integrates with Google Maps

Google Maps WMS Example

Yankee Foliage

MapServerWMS

counties layer

Colored polygons

Google Maps KML Example

ACFISH2 KML

Google Earth WMS Example

Atlas of CanadaMapServer – WMS, Lakes and Reservoirs layer

Google Earth – NOAA Example

National Weather Service – Doppler Radar locations KML

Google Earth KML Example

ACFISH2 KML

Google Earth Plugin Example

Google Maps Integration

Visualization Alternative

OpenLayers

Open source Javascript library, allows displaying dynamic map data in web browsers

API – Google MapsThe Open Planning Project (same as

GeoServer)

Data Sources: GeoServer, MapServer, Google, WMS, KML,

etc.

OpenLayers Example

ACFISH2 KML

OpenLayers, GeoServer, & PostGIS

Richard Franks USM Thesis Project