3D Maps

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Three dimensional photos and maps can help resource managers quickly analyze hydrologic, aesthetic, habitat type, fire suppression and other site management factors. Once mastered, the steps in creating 3D land images are fairly simple.

Five programs featured in the Digital Grove Toolbox will easily generate 3D views:

  • 3DEM first loads a Digital Elevation Model, which can then be rotated and viewed from any angle. You can work with just the Digital Elevation Model if you wish, but the real power of 3DEM is its ability to add an overlay or "skin" from a 2D image over the top of the terrain model (click Figures B-D, above, for information about how the views were created).

  • 3DField generates perspective views of Digital Elevation Models like 3DEM, but it excels in the ability to create striking 3D maps of data as shown in the following example (click the image for a full-screen view). Look here for a short  tutorial on how this map was made.

  • Global Mapper produces a simple 3D view from a vertical perspective if you load a Digital Elevation Model (DEM) and turn on hill-shading. You can use the Control Center/Options command to apply a bitmap layer as a texture map to the DEM for a 3D effect including advanced blending capabilities for raster layers (Figure A).


  • Also, check out NASA's World Wind and Google Earth. Both programs download digital terrain models and geographic imagery automatically from web servers. All you need to do is navigate around the globe to the place you want to view. Broadband Internet and a robust PC are required for the programs to work.

Below are three images that show (1) a conventional aerial photo, (2) a bare 3D terrain model and (3) the previous two elements combined. Note that the hill shadows, which are not the same in the second and third images, illustrate how the position of the light source can be moved in 3DEM. You'll get a more realistic overlay image in 3DEM if you adjust the "sun" position to correspond with the shadows in the original aerial photo.

Overlay Techniques

3DEM works with two layers: the elevation model and one overlay image. As such, it does not have the ability of the free TatukGIS Viewer or Global Mapper to add multiple data layers. By using 3DEM and the TatukGIS Viewer or Global Mapper together, you can have the best of both programs. These programs can be used to produce overlays that incorporate multiple geospatial data layers. Export a TatukGIS Viewer image (which is saved with georeferencing information) or a screen capture of a Global Mapper image to use it as an overlay in 3DEM.

3DEM can use images from many sources: screen captures, Digital Ortho Photos, USGS Digital Raster Graphics, GeoTiff files, TerraServer images, etc. The trick is to be able to register the overlay image so that it exactly lines up with the underlying DEM. 3DEM will automatically align georeferenced overlays. For scanned or captured images with georeferencing information, 3DEM has a geo-referencing dialog box. The user places two crosshair markers on the overlay image, entering the latitude and longitude of the two points (generally a point in the upper left and one in the lower right of the overlay).

3D Animations

After creating an overlay view in 3DEM, you can produce animated flyover movies. You can also make a movie of the 3D view rotated on an center axis. If you have a broadband Internet connection, click here for a small (678KB) sample animation of Devil's Lake State Park, Wisconsin. (The animation is minimized in size for the web. 3DEM will generate vivid, large animations, but they are impractical to serve on the Internet due to their large file size.)

For additional ideas, see the gallery at 3DEM. To delve further into the creation of interactive 3D scenes and ecological and geophysical modeling, visit the Virtual Terrain Project.

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