These maps are coded in VRML 2.0 with External Authoring Interface, JavaScript, and Java applets. These are intended to demonstrate the flexibility and adaptability that digital maps in VRML can achieve.

Since VRML EAI is involved, your browser must have Cosmo Player plug-in to view the maps. Check out VRML 2.0 EAI FAQ if needed.

User Interface

1. At first, choose meters or feet by selecting its button.
2. Choose one of the two coloring modes: continuous and discrete.
3. Then, change any elevation value in the color legend.
   If the continuous mode is selected, the input elevations will have their corresponding colors; the rest will have colors linearly interpolated in RGB space, just as you expect.
   If the discrete mode is selected, the input elevations and ABOVE will have their corresponding colors, say,

   Color Legend    Rule
   White     5000	when elevation >= 5000, then colored in white.
   Dark wood 3750	when 5000 > elevation >= 3750, then colored in dark wood.
   Wood      3000	when 3750 > elevation >= 3000, then colored in wood.
   .....
   

4. You have to click on Coloring button to activate the color update. Please be patient. This will take several seconds to complete. Click on Reset button to reset the elevation values to their default ones.
5. You can input a number into the text field for the exaggeration scale to exaggerate the elevation. Or, by clicking any of the four buttons - up, UP, DN, dn - to adjust the scale. The text field will show the current exaggeration scale.

Since the Java applet that updates the colors does not run very fast, the response time for color changing takes a few seconds, which depends on the size of data and the power of your local machine that executes the applet. It takes me more than 4 seconds on my Indigo 2.

Preview some screen shots without using a VRML plug-in: 1, 2, and 3.

Try this dymamic color legend for the USA map.