Add US-NC boundaries

- update readme

LayerData.js

@@ -135,6 +135,7 @@ export default class LocData {
             'US-NC': [
                 { title: 'TOT NHT', file: '..\/US-common\/tot.geojson' },
                 { title: 'AT', file: '..\/US-common\/at.geojson' },
+                { title: 'PAD-US Fee', file: 'PADUS3_0Fee_StateNC.geojson' },
                 { title: 'Parks', file: 'parks-US-NC.geojson' },
             ],
             'US-ND': [

readme.md

@@ -1,18 +1,37 @@
-# OpenLayers + Vite
+# POTAMAP Online
 
-Uses Node.js, openlayers, and Vite use this to get started
+_Or POTAMAP openlayers_
 
-    npm install ol
+Displays POTA park pins along with map boundaries from US government supplied GIS data. Namely the source is the [Protected Areas Database of the United States](https://www.sciencebase.gov/catalog/item/62226321d34ee0c6b38b6be3) (PAD-US)
+
+## Building
+
+Uses Node.js, openlayers, and Vite. With node.js installed, use this to get started:
+
+    $ npm install
+
+To run the app use:
+
+    $ npm run start
 
 ## Notes
-some maps are simplified using mapshaper: 
+
+Some geojson boundary files need be tweaked with a GIS tool called mapshaper
+
+Install with `npm install -g mapshaper`
+
+
+Then the maps can simplified (thus reducing the file size) using mapshaper: 
 
     mapshaper .\PADUS3_0Designation_StateNV.geojson -simplify dp 30% keep-shapes -o format=geojson .\simple.geojson
 
-To merge some geomoerty in geojson files. 1st output the properties into a csv file
+### Merging park shapes
+
+To merge some geomoerty in geojson files, first output the properties into a csv file:
+
     mapshaper .\simple.geojson -o simple.csv
 
-Copy and paste the name column (header+data) into a new column and rename it MERGED
+Edit the csv file. Copy and paste the name column (header+data) into a new column and rename it MERGED
 
 Then run the following command to join the shapes by their name and dissolve the inner
 geometry (it also keeps the original properties)
@@ -30,6 +49,8 @@ Dissolving trails created from potamap_tool:
 
 mapshaper .\safe.geojson -dissolve "NAME,NAME_EXT" -o format=geojson .\safe2.geojson
 
+This should keep the NAME property and NAME_EXT property in tact.
+
 ## Original setup instructions
 
 This example demonstrates how the `ol` package can be used with [Vite](https://vitejs.dev/).