Build Terrain (3D Analyst)

Summary

Performs tasks required for analyzing and displaying a terrain dataset.

Usage

• This tool will need to be used after initially defining the features that participate in a terrain, making subsequent modifications to the features that participate in the terrain, or modifying the terrain pyramid definition.

• It is more efficient to make a collection of edits followed by one build rather than running a build after each individual edit.

Parameters

Dialog

Label	Explanation	Data Type
Input Terrain	The terrain dataset to process.	Terrain Layer
Update Extent (Optional)	Recalculates the data extent of a window-size-based terrain dataset when the data area has been reduced through editing. It is not needed if the data extent has increased or if the terrain dataset is z-tolerance based. It will scan through all the terrain data to determine the new extent. Maintain Extent— The extent of the terrain dataset will not be recalculated. This is the default. Update Extent— The extent of the terrain dataset will be recalculated.	String

Derived Output

Label	Explanation	Data Type
Updated Input Terrain	The updated terrain.	Terrain Layer

Python

arcpy.ddd.BuildTerrain(in_terrain, {update_extent})

Name	Explanation	Data Type
in_terrain	The terrain dataset to process.	Terrain Layer
update_extent (Optional)	Recalculates the data extent of a window-size-based terrain dataset when the data area has been reduced through editing. It is not needed if the data extent has increased or if the terrain dataset is z-tolerance based. It will scan through all the terrain data to determine the new extent. NO_UPDATE_EXTENT— The extent of the terrain dataset will not be recalculated. This is the default. UPDATE_EXTENT— The extent of the terrain dataset will be recalculated.	String

Derived Output

Name	Explanation	Data Type
derived_out_terrain	The updated terrain.	Terrain Layer

Code sample

BuildTerrain example 1 (Python window)

The following sample demonstrates the use of this tool in the Python window.

arcpy.env.workspace = 'C:/data'
arcpy.ddd.BuildTerrain('test.gdb/featuredataset/terrain')

BuildTerrain example 2 (stand-alone script)

The following sample demonstrates the use of this tool in a stand-alone Python script.

"""****************************************************************************
Name: Create Terrain from TIN
Description: This script demonstrates how to create a terrain dataset using
             features extracted from a TIN. It is particularly useful in
             situations where the source data used in the TIN is not available,
             and the amount of data stored in the TIN proves to be too large
             for the TIN. The terrain's scalability will allow improved
             display performance and faster analysis. The script is designed
             to work as a script tool with 5 input arguments.
****************************************************************************"""
# Import system modules
import arcpy

# Set local variables
tin = arcpy.GetParameterAsText(0) # TIN used to create terrain
gdbLocation = arcpy.GetParameterAsText(1) # Folder that will store terran GDB
gdbName = arcpy.GetParameterAsText(2) # Name of terrain GDB
fdName = arcpy.GetParameterAsText(3) # Name of feature dataset
terrainName = arcpy.GetParameterAsText(4) # Name of terrain

try:
    # Create the file gdb that will store the feature dataset
    arcpy.management.CreateFileGDB(gdbLocation, gdbName)
    gdb = '{0}/{1}'.format(gdbLocation, gdbName)
    # Obtain spatial reference from TIN
    SR = arcpy.Describe(tin).spatialReference
    # Create the feature dataset that will store the terrain
    arcpy.management.CreateFeatureDataset(gdb, fdName, SR)
    fd = '{0}/{1}'.format(gdb, fdName)
    # Export TIN elements to feature classes for terrain
    arcpy.AddMessage("Exporting TIN footprint to define terrain boundary...")
    boundary = "{0}/boundary".format(fd)
    # Execute TinDomain
    arcpy.ddd.TinDomain(tin, tinDomain, 'POLYGON')
    arcpy.AddMessage("Exporting TIN breaklines...")
    breaklines = "{0}/breaklines".format(fd)
    # Execute TinLine
    arcpy.ddd.TinLine(tin, breaklines, "Code")
    arcpy.AddMessage("Exporting TIN nodes...")
    masspoints = "{0}/masspoints".format(fd)
    # Execute TinNode
    arcpy.ddd.TinNode(sourceTIN, TIN_nodes)
    arcpy.AddMessage("Creating terrain dataset...")
    terrain = "terrain_from_tin"
    # Execute CreateTerrain
    arcpy.ddd.CreateTerrain(fd, terrainName, 10, 50000, "",
                            "WINDOWSIZE", "ZMEAN", "NONE", 1)
    arcpy.AddMessage("Adding terrain pyramid levels...")
    terrain = "{0}/{1}".format(fd, terrainName)
    pyramids = ["20 5000", "25 10000", "35 25000", "50 50000"]
    # Execute AddTerrainPyramidLevel
    arcpy.ddd.AddTerrainPyramidLevel(terrain, "", pyramids)
    arcpy.AddMessage("Adding features to terrain...")
    inFeatures = "{0} Shape softclip 1 0 10 true false boundary_embed <None> "\
             "false; {1} Shape masspoints 1 0 50 true false points_embed "\
             "<None> false; {2} Shape softline 1 0 25 false false lines_embed "\
             "<None> false".format(boundary, masspoints, breaklines)
    # Execute AddFeatureClassToTerrain
    arcpy.ddd.AddFeatureClassToTerrain(terrain, inFeatures)
    arcpy.AddMessage("Building terrain...")
    # Execute BuildTerrain
    arcpy.ddd.BuildTerrain(terrain, "NO_UPDATE_EXTENT")
    arcpy.GetMessages()

except arcpy.ExecuteError:
    print(arcpy.GetMessages())
except Exception as err:
    print(err)

Environments

Current Workspace, Extent, Auto Commit

Licensing information

• Basic: Requires 3D Analyst
• Standard: Requires 3D Analyst
• Advanced: Requires 3D Analyst