LCP Routing

# ---------------------------------------------------------------------------
# Final.py
# Created on: 5/12/2014
# Created by: Noah C. Huntington
# Copyright: Furman Land Surveyors, Inc. 2014 - (806)374-4246
# Description:  Calculates Multiple Least Cost Paths Between Substations
# ---------------------------------------------------------------------------

# Import modules
import arcpy
import os
from arcpy import env
arcpy.env.overwriteOutput = 1
from arcpy.sa import *
import math

# Check out any necessary licenses
arcpy.CheckOutExtension("Spatial")

# Declare variables for tool parameters
subs  = arcpy.GetParameterAsText(0)
Field = arcpy.GetParameterAsText(1)
originValue = arcpy.GetParameterAsText(2)
destValue   = arcpy.GetParameterAsText(3)
lines = arcpy.GetParameterAsText(4)
Dem = arcpy.GetParameterAsText(5)
landuse = arcpy.GetParameterAsText(6)
wells = arcpy.GetParameterAsText(7)
savepath = arcpy.GetParameterAsText(8)

# Weights applied to criteria
slope_Weight = 10
landuse_weight = 90

count = 0

# Set Geoprocessing environments
arcpy.env.cellSize = 90
ws = arcpy.env.workspace = savepath + '\\Scratch.gdb'
sr = arcpy.SpatialReference(2275)

'''
subs  = r"G:\Xcel\Route Tool\Southwest\Data.gdb\Subs_4201"
Field = "Name"
originValue = "Hillside"
destValue   = "Coulter"
lines = r"G:\Xcel\Route Tool\Southwest\Data.gdb\OLS_Lines_Proj"
Dem =r"G:\Xcel\Route Tool\Southwest\Data.gdb\Dem_4201"
landuse = r"G:\Xcel\Route Tool\Southwest\Data.gdb\lu_4201"
wells = r"G:\Xcel\Route Tool\Southwest\Data.gdb\wells_4201"
savepath = r"G:\Xcel\Route Tool\Southwest\Hillside"
'''



#   --------------------------------------------------------------------------------------
#   Functions and variables for savepaths are declared in this section
#   Dynamic path for out polylines
#   --------------------------------------------------------------------------------------
Output_polyline =  os.path.join(savepath  + "\\Results.gdb"  + "\\LCP_" + chr(count + 65))

def get_backlink(count):
    return os.path.join(savepath  + "\\Scratch.gdb"  + "\\backlink_" + str(count))

def get_LCP(count):
    return os.path.join(savepath  + "\\Scratch.gdb"  + "\\LCP_" + chr(count + 65))

def get_costRaster(count):
    return os.path.join(savepath  + "\\Scratch.gdb"  + "\\cost_Raster_" + str(count))

def get_weighted_Raster(count):
    return os.path.join(savepath  + "\\Scratch.gdb"  + "\\weighted_Raster_" + str(count))






#   -----------------------------------------------------------------------------------
#   This function retrieves the coordinates of the endpoints
#       It is called for during the while loop while running extractbypoints
#   -----------------------------------------------------------------------------------

def get_Coordinates():

    #Create SQL statement
    where_clause_envelope =  "\"{}\" = '{}'" "or " "\"{}\" = '{}'".format(Field,originValue,Field,destValue) #produces: "Name" = 'Amarillo 34th St'or "Name" = 'Coulter


    #Create temp layer for origin and destination
    Ends =  os.path.join(savepath  + "\\Scratch.gdb"  + "\\Ends_" + str(count))
    Ends_fl = arcpy.MakeFeatureLayer_management(subs, Ends, where_clause_envelope)

    fields = ["SHAPE@X","SHAPE@Y"]
    cursor = arcpy.da.SearchCursor(Ends_fl, fields)
    record1 = next(cursor)
    record2 = next(cursor)
    x1 = record1[0]
    x2 = record2[0]
    y1 = record1[1]
    y2 = record2[1]

    pointList = [arcpy.Point(x1, y1),
         arcpy.Point(x2,y2)]

    return pointList

def get_buffer_Distance():
    # This function determines the buffer distance
    #   which is performed in order to determine study area before undergoing raster processing

    #Create SQL Statement
    where_clause_envelope =  "\"{}\" = '{}'" "or " "\"{}\" = '{}'".format(Field,originValue,Field,destValue)#produces: "Name" = 'Amarillo 34th St'or "Name" = 'Coulter

    #Create temp layer for origin and destination
    Points = arcpy.MakeFeatureLayer_management(subs, "Subs_Selection", where_clause_envelope)

    Line = arcpy.PointsToLine_management(Points, arcpy.Geometry(),"","","NO_CLOSE")
    length = 0
    for geometry in Line:
        length += geometry.length

    miles = length/5280
    if miles > 10:
        Buffer = 20*5280
    else:
        Buffer = length*2

    return Buffer



#   --------------------------------------------------------------------------------------
#   This is the main section of the tool
#
#   --------------------------------------------------------------------------------------

def main():
    count = 0
    arcpy.CreateFileGDB_management(savepath, "Scratch.gdb")
    arcpy.CreateFileGDB_management(savepath, "Results.gdb")

    arcpy.AddMessage("Data will be saved to: {0}" .format(ws))

    #Create SQL statement
    where_clause_envelope =  "\"{}\" = '{}'" "or " "\"{}\" = '{}'".format(Field,originValue,Field,destValue)#produces: "Name" = 'Amarillo 34th St'or "Name" = 'Coulter

    #Create temp layer for origin and destination
    subset = arcpy.MakeFeatureLayer_management(subs, "Subs_Selection", where_clause_envelope)

    #Create extent polygon from selected subs
    arcpy.AddMessage("Computing Extents...")
    arcpy.MinimumBoundingGeometry_management(subset, "Subs_Env", "", "ALL")

    #Buffer the envelope
    arcpy.AddMessage("Buffering Extent Polygon...")
    Buffer = get_buffer_Distance()
    arcpy.Buffer_analysis("Subs_Env", "Envelope_Buffer", str(Buffer) + " Feet", "FULL", "ROUND", "ALL", "")

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