100 likes | 341 Views
The Geographic Information System Tool (GIST): A New Tool for Visualizing Geographic Data. Alison M. Eyth, Prashant Pai MCNC Environmental Modeling Center October 22, 2002. PAVE Limitations. Graphics are written in X-windows / Motif (not good for PCs)
E N D
The Geographic Information System Tool (GIST): A New Tool for Visualizing Geographic Data Alison M. Eyth, Prashant Pai MCNC Environmental Modeling Center October 22, 2002 MCNC Environmental Modeling Center
PAVE Limitations • Graphics are written in X-windows / Motif (not good for PCs) • Must be compiled separately for each platform • Only a few maps provided (states, counties, roads, rivers), with limited rendering styles • Cannot plot data in polygons – only rectangular grid cells and limited facilities for observations • Plots accessible over web only as static images MCNC Environmental Modeling Center
Current GIST Features • Create maps of points, lines, polygons • data from Shapefiles or ASCII format • Data sets drawn in layers, • can be moved up, down, sent to top or bottom, hidden/shown • Configurable data object styles • colors, line thickness, point symbols • Set map projection / ellipsoid • Probe data attributes • Thematic mapping • Querying • Display mouse coordinates, zoom, overview, print MCNC Environmental Modeling Center
Potential New Data Types • Emission inventories and surrogates • Air quality and meteorological observations • Slices of regular grid air quality model results • Variable grid model results • Multimedia model results (already have prototype) • Water quality model results • Flight paths • Can already support points, lines, polygons from any type of shapefile (e.g. population data, land use) MCNC Environmental Modeling Center
Behind the Scenes of GIST • Java program • Portable across platforms • Object-oriented / extensible • Runs as desktop application or over web as applet • Uses JLooxGIS class library (www.loox.com) • Basic plotting of points, lines, polygons on map • Coordinate transformations • Zooming • Printing • Panning / map overview • Layer control • Not open-source MCNC Environmental Modeling Center
Layer Library • Maintains layers loaded between GIST sessions • “Friendly names” can be specified for data sets • Separates file format from objects in display MCNC Environmental Modeling Center
Probing to show Data Attributes MCNC Environmental Modeling Center
Thematic map and Layer Options MCNC Environmental Modeling Center
Query Results as Map and Table MCNC Environmental Modeling Center
Future Directions • Enhancements dependent on funding source • Currently MCNC funded proprietary software • Animation (within data set and across data sets) • Scripting language • Formula language (like PAVE) • Save images to graphics formats • Show satellite pictures and DTED • Save images and data to files • Improved probing, overview, queries, resizing • Save configuration and restart using it • Data subsetting / improved memory management MCNC Environmental Modeling Center