12/17/98 Final Presentation

Professor E. Nelson, Dept. Geography, SDSU
	San Diego State University	Education Center on Computational science & Engineering
a partnership activity of the NPACI and San Diego Supercomputer Center

1. To begin, you need spatial data in a format that ArcView understands. This demo used the U.S. counties shapefile supplied with ESRI’s software.
   
   
2. Create a view and add the shapefile(s) with which you wish to work.
   
   
3. Use ArcView’s Query Builder to parse out the region of interest, then set an appropriate projection using the View-Properties command.
   
   
4. Use the Legend Editor to classify the areas represented in the shapefile and to set an appropriate color scheme. For the data in this demo, both of these options were manually customized. The resulting view in this demo is a static choropleth map of the region – a traditional way of visualizing population density in cartography, where lighter colors are assigned to areas of lower densities and darker colors are assigned to areas of higher densities.
   
   
5. Load the 3-d Analyst extension, then create a 3-d scene view. Copy the theme created in the view and paste it into the 3-d Scene Viewer.
   
   
6. Using the Theme-3d Properties command, extrude the areas in the shapefile by adding the chosen attribute values to the base height. This will give you a prism map of the same data – essentially a 3-d rendering where the areas on the map are not only color-coded, but also vary in z height according to the selected attribute value. In this demo, the prism map was extruded on 1990 population densities multiplied by a factor of 100.
   
   
7. Use the 3-d Scene-Properties to set an appropriate sun angle and azimuth. The options used for these views were High and Northwest.
   
   
8. Create a second 3-d scene in which a contour map of the data will be created. Contours are the traditional cartographic technique for displaying data that can be conceptualized as continuous. For this scene, choose the Surface – Create TIN from features command to have ArcView create a continuous surface on the basis of the attribute data recorded for each county.
   
   
9. Use the Legend Editor to manually reclassify the data and to choose an appropriate color scheme for your data. Reclassification should take into account the contour intervals you wish to use, so that the classification matches the contour intervals. Here, the interval was set to 100.
   
   
10. Choose Surface-Create Contours to create a contour overlay for the continuous surface. Here, the interval was again set to 100. Use the Legend Editor to customize the line symbolization – graduated color lines were used for the demo.
    
    
11. Since the contours do not show up well in the 3-d environment when exported for the web page, copy and paste the 2 themes back into a new 2-d view. This view is what will be exported to the web page.
    
    
12. Create one last 3-d scene viewer and cut and paste the TIN surface from the previous viewer into it. Reclassify this scene to match the classification of the 1^st view made, then use the Vertical exaggeration property under the 3d Scene-Properties command to create a continuous 3-d rendering of the data.
    
    
13. For the choropleth and contour maps in the standard views, use a screen grabber program like SnagIt32 to capture the map image and save it as a .jpg file. Do the same for the legends for those maps.
    
    
14. For the prism map and the continuous 3-d rendering, export both of those 3-d scenes to a VRML format using the File-Export command. Use the screen grabber program to capture their legends.
    
    
15. Load the exported files and legends into an html page. Load the CosmoPlayer Plug-in for your browser.
    
    
16. Use JAVA to coordinate the viewing of the 2 3-d files in CosmoPlayer.