ShadedRelief

Summary

Creates a color 3D representation of the terrain by merging the images from the elevation-coded and hillshade methods.

Discussion

For more information about how this function works, see the Shaded Relief raster function.

The referenced raster dataset for the raster object is temporary. To make it permanent, you can call the raster object's save method.

Syntax

ShadedRelief (raster, azimuth, altitude, {z_factor}, {colormap}, {colorramp}, {slope_type}, {ps_power}, {psz_factor}, {remove_edge_effect})

Parameter	Explanation	Data Type
raster	The input DEM.	Raster
azimuth	Azimuth is the sun's relative position along the horizon (in degrees). This position is indicated by the angle of the sun measured clockwise from due north. An azimuth of 0 degrees indicates north, east is 90 degrees, south is 180 degrees, and west is 270 degrees. (The default value is 315)	Double
altitude	Altitude is the sun's angle of elevation above the horizon and ranges from 0 to 90 degrees. A value of 0 degrees indicates that the sun is on the horizon, that is, on the same horizontal plane as the frame of reference. A value of 90 degrees indicates that the sun is directly overhead. (The default value is 45)	Double
z_factor	The z-factor is a scaling factor used to convert the elevation values for the following purposes: Convert the elevation units (such as meters or feet) to the horizontal coordinate units of the dataset, which may be feet, meters, or degrees. Add vertical exaggeration for visual effect. If the x,y units and z units are in the same units of measure, the z-factor should be set to 1. The z-values of the input surface are multiplied by the z-factor when calculating the final output surface. (The default value is 1)	Double
colormap [colormap,...]	The color map used to render the raster. This can be provided as a list or dictionary. (The default value is None)	List
colorramp	The name of the color ramp. This can be provided as a string specifying a color ramp name supported in ArcGIS AllSource, such as Yellow to Red, or Slope. This can also be provided as a dictionary. For more information, see Color ramp objects. (The default value is Elevation #1)	String
slope_type	The inclination of slope can be output as either a value in degrees or percent rise. Specify one of the following: DEGREE, PERCENTRISE, or SCALED. For more information, see Slope function. (The default value is DEGREE)	String
ps_power	Accounts for the altitude changes (or scale) as the viewer zooms in and out on the map display. It is the exponent applied to the pixel size term in the equation that controls the rate at which the z-factor changes to avoid significant loss of relief. This parameter is only valid when slope_type is SCALED. (The default value is 0.664)	Double
psz_factor	Accounts for changes in scale as the viewer zooms in and out on the map display. The value controls the rate at which the z-factor changes. This parameter is only valid when slope_type is SCALED. (The default value is 0.024)	Double
remove_edge_effect	Using this option will avoid any resampling of artifacts that may occur along the edges of a raster. The output pixels along the edge of a raster or next to pixels without a value will be populated with NoData. It is recommended that you use this option only when there are other rasters with overlapping pixels available. When overlapping pixels are available, these areas of NoData will display the overlapping pixel values instead of being blank. False—Bilinear resampling will be applied uniformly to resample the output. True—Bilinear resampling will be used to resample the output, except along the edges of the rasters or next to pixels of NoData. These pixels will be populated with NoData. This will reduce any sharp edge effects that may otherwise occur. (The default value is False)	Boolean

Return Value

Data Type	Explanation
Raster	The output raster.

Code sample

ShadedRelief example 1

This example creates a shaded relief:

# Import system modules
import arcpy
from arcpy.sa import *

# Set environment settings
env.workspace = "C:/data"

# input raster
inRasters= = "input_raster.tif"

# use built-in colorramp slope
colorramp_name = "Slope"

# Execute arcpy.sa.ShadedRelief
shadedRelief = ShadedRelief(imagePath1, azimuth=315, altitude=45, z_factor=1, colorramp=colorramp_name, slope_type = "SCALED",
                            ps_power=0.664, psz_factor=0.024, remove_edge_effect=False)
shadedRelief.save("C:/output/shadedrelief_output2.tif")

ShadedRelief example 2

This example creates a shaded relief:

# Import system modules
import arcpy
from arcpy.sa import *
import random

# Set environment settings
env.workspace = "C:/data"

# input raster
inRasters= = "input_raster.tif"

# generate a color map list
color_map = []
for i in range(1, 255):
    # generate random color
    red = random.randrange(0, 256)
    green = random.randrange(0, 256)
    blue = random.randrange(0, 256)
    value = i
    color_map.append([value, red, green, blue])

# Execute Sample
shadedRelief = ShadedRelief(imagePath1, azimuth=315, altitude=45, z_factor=1, colormap=315, slope_type = "DEGREE")
shadedRelief.save("C:/output/shadedrelief_output.tif")