add-seafloor-slope.py

import arcpy

in_raster = r"\\psf\Home\Documents\ArcGIS\Default.gdb\rastercalc13"
in_raster_obj = arcpy.Raster(in_raster)
arcpy.env.extent = in_raster
arcpy.env.cellSize = in_raster
arcpy.env.overwriteOutput = 1

# Raster already projected earlier in CreateProject.py process
arcpy.CheckOutExtension("Spatial")
# 2 - Con to make values > 0 = 1, else 0, use this next
ones_zeros_con = arcpy.sa.Con(in_raster_obj, 1, 0, "VALUE > 0")
# 3 - Extract values = 1 to new raster, use this next
extracted_ones = arcpy.sa.ExtractByAttributes(ones_zeros_con, "VALUE = 1")
# 4 - Do Euc Dist on extent of in_raster, using the land values of 1. This will calc the nearest distance to shore
#     for every cell that represents water, not land
euc_dist = arcpy.sa.EucDistance(extracted_ones)
# 5 - Flip the ED values and make them go from  0->100 instead of 0->max_elev. Do this by multiplying each cell by
#     (100/-max_elev)
max_elev = euc_dist.maximum
conv_to_hundred_con = arcpy.sa.Con(euc_dist, (euc_dist * (100/-max_elev)), euc_dist, "VALUE > 0")
# 6 - Add 100 to every cell that is less than 100, which flips the numbers offshore and makes the shoreline 100m and
#     as you go out to sea, the depths taper down to 0
con_reverse_slope = arcpy.sa.Con(conv_to_hundred_con, conv_to_hundred_con + 100, conv_to_hundred_con, "VALUE < 100")
# 7 - For values = 100 (land only values), add the values from original in_raster back
slope_plus_orig_land_con = arcpy.sa.Con(con_reverse_slope, con_reverse_slope + in_raster_obj, con_reverse_slope,
                                        "VALUE = 100")
# Save. Now have a raster where lowest point underwater is very close to 0 (positive), shoreline (sea level) is 100, and
#       all land elevation values are (in_raster + 100). Now in Vue set sea level to 100, subtract 100 from the radius
#       of the earth, add 100m to camera and wtgs, and all is good. We get a nice slope down from shore to the ocean
#       botton and no abyss which results in the sea being dark blue
slope_plus_orig_land_con.save(r"\\psf\Home\Documents\ArcGIS\Default.gdb\scripted_slope_cape1")

arcpy.CheckInExtension("Spatial")