update readme, add phantom script, original screengrabs

README.md

@@ -5,13 +5,29 @@ The morning of the January 2016 blizzard, my husband showed me Google Maps on hi
 
 When we got home, I wrote a quick, crude [PhantomJS](http://phantomjs.org) script to take regular screenshots of Google Maps for the rest of the day. Then I selected the screenshots I wanted to use and turned them into a GIF using [ImageMagick](http://www.imagemagick.org/script/convert.php).
 
+The final gif includes screengrabs taken roughly every half-hour. There's a gap between 2 and 4 p.m. (sadly, right about when the storm hits Washington, D.C., in earnest) when my script threw an error and I didn't notice.
+
 This was a crude, pulled-together-in-10-min-or-so project, so nothing is done in a clean or optimized way. I'm saving it here on GitHub mostly for my own future reference.
 
 ----------
 
 ## Screencapture
 
-The [PhantomJS](http://phantomjs.org) script (TK TK TK)
+I wrote a crude [PhantomJS](http://phantomjs.org/screen-capture.html) script ([here it is](mapcapture.js)) to snap screengrabs of [Google Maps](https://www.google.com/maps/@38.6337794,-76.8123652,6z/data=!5m1!1e1) (for traffic) and [WNYC's weather radar](http://project.wnyc.org/storm-radar/) (which I didn't end up using) every 5 minutes or so. I added an extra 5-second delay to help make sure that all/most of the page had rendered before PhantomJS captured the image. Even then, about a fourth of my Google Maps screencaps came out mostly blank, with just the map search bar and other wrapper items and no actual map.
+
+Most PhantomJS scripts include a `phantom.exit();` command somewhere. I excluded it because I wanted it to keep running until I cancelled it (ctrl-C) in terminal.
+
+Since I already had npm on my machine, I used it to install PhantomJS:
+
+```
+npm install phantomjs
+```
+
+And to run my script:
+
+```
+phantomjs mapcapture.js
+```
 
 ----------
 

mapcapture.js

@@ -0,0 +1,49 @@
+var intervalLength = 300000;
+
+function screenCap() {
+	loadMap();
+	loadRadar();
+}
+
+function loadMap() {
+	var page = require('webpage').create();
+
+	page.viewportSize = {
+	  width: 1200,
+	  height: 1200
+	};
+
+	page.open('https://www.google.com/maps/@38.6337794,-76.8123652,6z/data=!5m1!1e1', function() {
+		map_wait();
+	});
+
+	function map_wait() {
+		setTimeout(function() {
+			var timestamp = (new Date()).toLocaleString();
+			page.render('screengrabs/map-' + timestamp + '.png');
+		}, 5000);
+	}
+}
+
+function loadRadar() {
+	var page = require('webpage').create();
+
+	page.viewportSize = {
+	  width: 1200,
+	  height: 1200
+	};
+
+	page.open('http://project.wnyc.org/storm-radar/', function() {
+		radar_wait();
+	});
+
+	function radar_wait() {
+		setTimeout(function() {
+			var timestamp = (new Date()).toLocaleString();
+			page.render('screengrabs/radar-' + timestamp + '.png');
+		}, 5000);
+	}
+}
+
+screenCap();
+var interval = setInterval(screenCap, intervalLength);