Team Members

Dependencies

Project Summary

Processing Steps

• "Ian Erickson" ierickson@tableau.com
• "Arielle Simmons-Steffen" asimmons-steffen@tableau.com
• "Matt Kenny" mkenny@tableau.com

ShieldLabels.py:

fiona shapely re os sys stat shutil

Nodify.py:

fiona time shapely

The scripts ShieldLabels.py and Nodify.py are designed to generate shield label points from the shapefile extract of osm derived datasets.

<a name-"processing-steps">Processing Steps

1. User projects (EPSG: 3857) and spatially selects the region (either USA or Global) that will be run through ShieldLabels.py and Nodify.py. A 'ref' tag is REQUIRED to be in this dataset.

User must take caution to make sure the utf-8 encoding is preserved during the spatial select.

2. The spatially selected boundaries are run through ShieldLabels.py. This script parses the 'ref' tag into the necessary ['label'] field and a ['shield_typ'] field types. IF THE 'ref' tag is not called 'ref' tag. Line 84 in the function ShieldLabels.ShieldLabels.dissolve is where you can reset the field name. In order to run ShieldLabels.py the user must input the following:

   inputFile = spatially selected USA/Global osm_motorways shapefile

   outputFile = a shapefile named of the users choosing

   region = a tag declaring whether to parse the spatially selected shapefile by it's region. Can be either 'USA' or 'Global'

   Example of input parameters:

   inputFile = r"I:\It_26\Python_Label_Shields_tool\code_for_data\osm_motorways_usa.shp" outputFile = r"I:\It_26\Python_Label_Shields_tool\data_result\osm_motorways_usa_shield_lines.shp" region = USA

3. Use shptree to generate a qix file for the new shield lines dataset

4. The outputFile from ShieldLabels.py is then run through Nodify.py. The output of Nodify.py will create the final dataset needed for inputing road shield points into the service. First step is to generate nodes (see LineTools.add_nodes) at a set interval=2000.

   Make sure that you use QGIS on the output shapefile to set ['PROCESSED'] = 'N' (see line: 144), before using it as an input for another file! is expected that you will run Nodify.LineTools.thin_node FIVE times for each region and create FIVE output files, beginning with radius: 4000.

   Example of input parameters:

   input_file = r"D:\work\osm_motorways\osm_world_labels.shp" output_file = r"D:\work\osm_motorways\osm_world_label_nodes_2000.shp" complete_file = r"D:\work\osm_motorways\osm_world_label_points_6000.shp"

   LineTools.add_nodes(input_file=input_file, output_file=output_file, interval=2000) LineTools.thin_nodes(input_file=output_file, output_file=complete_file, group_field='label', radius=6000)

   Example inputs for 'radius' are:

   USA & Global:

   • note: generate a new qix file for each of the output files before using it as an input

     • radius: 50000 (note: run on the 30000 output file) zoom: 9

     • radius: 30000 (note: run on the 16000 output file) zoom: 10

     • radius: 16000 (note: run on the 8000 output file) zoom: 11

     • radius: 8000 (note: run on the 4000 output file) zoom: 12

     • radius: 4000 zoom: 13

5. The user takes the 5 output files from Nodify.py and sets the zoom attribute according to the radius parameter (see above). Merge all 5 output files together into ONE shapefile. Generate a qix file. MANUALLY REMOVE ANY INCORRECT POINTS THAT WERE CAUSED BY THE SPATIAL SELECT.

For more details please see in-line comments in ShieldLabels.py & Nodify.py.