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Before You Begin

Data for generating landscape maps and models in ARC+ must be in one of the following formats:

ASCII files containing a list of X,Y and Z coordinates

ARC+ file containing geometric points in 3D space

ARC+ file containing text entities

ARC+ file containing open and/or closed polygons

Source data containing geometric points or text entities may be either built in ARC+ or imported using the Importing a DXF or DWG File (\dxfin or \dwgin) (see Files).

The system generates the maps and models by interpolating contours between specified points and/or coordinates.

Using ASCII Files

ASCII files used for generating topographic models must conform to the following conventions:

Files must contain only the required X,Y and Z coordinates. Delete all additional data such as column titles, row numbers, etc.

File extension must be *.xyz.

Coordinates must be entered in the order X Y Z.

Each column must be delineated by a space or a comma.

Space delineated:

Comma delineated:

IMPORTANT Invalid column delineation, such as an extra comma between columns, may distort the image of your model by translating the invalid character into a coordinate.

Using ARC+ Files

Source files may be in the form of an ARC+ or DXF/DWG file. Use the Importing a DXF or DWG File (\dxfin or \dwgin) command to import DXF files. The files can contain text or points.

ARC+ File Containing Geometric Points:

These ARC+ files consist of a series of point entities in 3D space. Each point represents a location on the surface of the terrain. Verify that the file contains only the required points.

NOTE Points may be arranged on a rectangular grid or irregularly in space.

ARC+ File Containing Text Entities:

These ARC+ files consist of a series of text entities, where the Z value is indicated by the text. The X Y values of the each text entity are indicated by the text justification point. Verify that the file contains only the required points.

NOTE Text entities may be arranged on a rectangular grid or irregularly in space.

ARC+ File Containing Polygons:

These ARC+ files contain open or closed polygons. The XYZ values of every point of each polygon are converted to points for terrain interpolation.

Related Topics

Creating a Terrain Model

Map and Model Types

Refining Your Terrain Model

Randomly Generated Fractal-Based Models