Procedure Library for using 3D Analyst

The purpose of this procedure library is to explain how to use 3D Analyst to present spatial data in a three dimensional format. This extension for ArcView allows you to create 3D models using DEM or other elevation maps, and layer your other themes on top of the DEM to get stunning models.

Andy Freed

5/25/01

Tools: ArcView 3.2, 3D Analyst Extension (esri)

Load 3D Analyst & Spatial Analyst extensions

· In ArcView, select both 3D analyst and Spatial Analyst from the extensions list in File\Extensions.

· Click OK.

Create a 3D scene

· In the project window, scroll down to the 3D Scene button and click on New.

· Adding themes is similar to a regular View. Click the Add Theme button to add a coverage to the scene.

· The first coverage should be a TIN (triangulated irregular network), which includes a Z coordinate for elevation information.

· When you add a TIN, you must select TIN from the data source list.

Add 2D themes to the 3D scene

· Adding a theme is the same as in the view. Once you add the feature or image, click it to make it active in the 3D Scene.

· It will not be visible because it does not have any Z values yet.

· Select the theme and choose 3D properties from the Theme menu

· You will Assign Base Height By the TIN surface in this example.

· You may want to offset the theme by a unit or two of the Z value so that it will be above the DEM surface.

Extruding 2D polygon features

· If you have a 2D polygon theme that you want to give height, like buildings, you can extrude the feature out from the surface of the TIN. This process gives the polygon a Z value, making it a 3d shape.

· To extrude a feature, select the polygon (only works with polygons) and select the 3D properties from the Theme menu.

· For the value that the polygon is extruded is in the same units as the TIN.

· If you want to shade the feature, check the box below the extrude option for dynamic shading.

Saving images for the 3D Scene

· You can save a still image of the scene by clicking the disk button on the scene. You can save the image as a JPEG or Tiff image.

3D fly-by of the Scene

· You can create a 3d fly-around of the scene by Exporting the scene to VRML. This option can be found in the File menu, but is of questionable use. The last VRML I exported only crashed every VRML program I used.

For additional information, see ArcView or Spatial Analyst help.

Modified: 6/05/2001