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Build Terrain Dataset from LAS

Description​

Creates a new geodatabase, feature dataset (hard-coded to "Lidar_data"), and terrain dataset (hard-coded to "Lidar_trn") from LAS files found in the input LAS folder.

Usage​

Creates a new geodatabase, feature dataset (hard-coded to "Lidar_data"), and terrain dataset (hard-coded to "Lidar_trn"). All points defined in the .las files present in the input directory are imported into "Lidar_mpt" feature class and are used as mass points when populating the terrain dataset. If the optional break line parameter is used, the 3D line is imported into "BreakLine3D" feature class and is used as a hard break line when populating the terrain dataset. If the optional replace polygon parameter is used, the 3D polygon is imported into "ReplacePoly3D" feature class and is used as a replace polygon when populating the terrain dataset.

Spatial reference for the feature dataset is based on the spatial reference of the first .las file in the input directory.

Only "bare earth" classified points (class code = 2) from the .las files are included in the created "Lidar_mpt" feature class.

Average point spacing is estimated at 1m.

The following terrain dataset parameters are used:

  • Average Point Spacing = 1m
  • Maximum Overview Size = 50,000
  • Pyramid Type = "Window Size"
  • Window Size Method = "Closest To Mean Z"
  • Secondary Thinning Method = "Mild"
  • Secondary Thinning Threshold = 0.18

The following terrain pyramid levels are added:

[2; 1,000], [4; 2,500], [8; 5,000], [16; 10,000], [32; 20,000], [64; 40,000]

The terrain dataset construction methodology is based on work by Dr. David E. James, USDA/ARS National Laboratory for Agriculture and the Environment, Ames, Iowa.

Parameters​

Parameter NameTypeDirectionData TypeDialog Reference
Input LAS FolderRequiredInputFolderInput folder with LAS files that will be used to build the terrain dataset. All *.las files in that folder will be used in the terrain dataset development. LAS files should have the same spatial reference.
Output FolderRequiredInputFolderOutput folder where the resulting geodatabase with terrain dataset will be placed.
Output Geodatabase NameRequiredInputStringName of the output geodatabase that will store the created terrain dataset. This database must not already exist. Include ".gdb" extension in the provided name (e.g. aaa.gdb).
Input 3D Break Line Feature ClassOptionalInputFeature Layer3D polyline feature class representing hard break lines to be incorporated into the terrain dataset. This is an optional layer.
Input 3D Replace Polygon Feature ClassOptionalInputFeature Layer3D polygon feature class representing replace polygons to be incorporated into the terrain dataset. This is an optional layer.