添加 Terrain 金字塔等级 (3D Analyst)
用法
每个金字塔等级以空格分隔的金字塔等级分辨率和参考比例对形式输入(例如,“20 24000”表示窗口大小为 20,参考比例为 1:24000,或者“1.5 10000”表示 z 容差为 1.5,参考比例为 1:10000)。
金字塔等级分辨率指的是将用于金字塔的 z 容错或窗口大小值。
- z 容差指定处于全分辨率下时可能出现的距 terrain 高程的最大偏差。
- 窗口大小定义细化高程点所用的切片区域,细化高程点即基于创建 terrain 时指定的窗口大小方法从切片区域选择一个或两个点。
参考比例表示显示金字塔等级所使用的最大地图比例。
-
向 terrain 添加新的金字塔等级会使其变得无效,因为 terrain 需要用从之前的金字塔等级采样得到的高程点填充金字塔。请在添加金字塔等级后使用构建 Terrain。
-
如果在 SDE 数据库中使用,则输入 terrain 将无法注册为版本。
语法
参数 | 说明 | 数据类型 |
in_terrain |
输入 terrain 数据集。 | Terrain Layer |
pyramid_level_definition ["<pyramid_level_resolution> <reference_scale>",...] |
z 容差或窗口大小以及将要添加到 terrain 中的各个金字塔等级的关联参考比例。每个金字塔等级以空格分隔的金字塔等级分辨率和参考比例对形式输入(例如,“20 24000”表示窗口大小为 20,参考比例为 1:24000,或者“1.5 10000”表示 z 容差为 1.5,参考比例为 1:10000)。金字塔等级分辨率可以浮点值形式提供,而参考比例必须以整数形式输入。 z 容差值表示处于全分辨率下时可能出现的距 terrain 高程的最大偏差;而窗口大小值定义细化高程点所用的 terrain 切片区域,细化高程点即基于创建 terrain 过程中定义的窗口大小方法从切片区域选择一个或两个点。参考比例表示强制显示金字塔等级所使用的最大地图比例。以大于此值的比例显示 terrain 时,将显示下一个最高的金字塔等级。 | String |
pyramid_type (可选) |
terrain 数据集使用的金字塔类型。ArcGIS 9.3 及更高版本中不使用此参数,因为此参数的用途是确保向后兼容使用 ArcGIS 9.2 编写的脚本和模型。 | String |
代码实例
下面的示例演示了如何在 Python 窗口中使用此工具:
import arcpy
from arcpy import env
arcpy.CheckOutExtension('3D')
env.workspace = 'C:/data'
arcpy.AddTerrainPyramidLevel_3d('test.gdb/featuredataset/terrain', 'WINDOWSIZE',
'2.5 10000; 5 25000; 10 50000')
下面的示例演示了如何在独立 Python 脚本中使用此工具:
"""****************************************************************************
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
import exceptions, sys, traceback
from arcpy import env
# 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:
arcpy.CheckOutExtension("3D")
# 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:
# Get the traceback object
tb = sys.exc_info()[2]
tbinfo = traceback.format_tb(tb)[0]
# Concatenate error information into message string
pymsg = "PYTHON ERRORS:\nTraceback info:\n{0}\nError Info:\n{1}"\
.format(tbinfo, str(sys.exc_info()[1]))
msgs = "ArcPy ERRORS:\n {0}\n".format(arcpy.GetMessages(2))
# Return python error messages for script tool or Python Window
arcpy.AddError(pymsg)
arcpy.AddError(msgs)
finally:
arcpy.CheckInExtension("3D")