filmStrip: initial commit

modules/filmStrip/filmStrip.js

@@ -0,0 +1,63 @@
+/**
+ * Renders a serie of screenshots of page being loaded
+ *
+ * Run phantomas with --film-strip option to use this module
+ */
+exports.version = '0.1';
+
+exports.module = function(phantomas) {
+	if (!phantomas.getParam('film-strip')) {
+		phantomas.log('To enable screenshots of page being loaded run phantomas with --film-strip option');
+		return;
+	}
+
+	var zoomFactor = 0.5;
+	//phantomas.setZoom(zoomFactor);
+
+	var util = phantomas.require('util'),
+		// throttling
+		SCREENSHOTS_MIN_INTERVAL = 75,
+		lastScreenshot = 0,
+		start = Date.now(),
+		// stats
+		timeTotal = 0,
+		screenshotsTotal = 0;
+
+	function screenshot() {
+		var now = Date.now(),
+			path;
+
+		// check when was the last screenshot taken (exclude time it took to render the screenshot)
+		if (now - lastScreenshot < SCREENSHOTS_MIN_INTERVAL) {
+			//phantomas.log('Film strip: skipped');
+			return;
+		}
+
+		path = util.format('filmstrip/screenshot-%d-%d.png', start, now - start - timeTotal);
+
+		phantomas.render(path);
+		lastScreenshot = Date.now();
+
+		phantomas.log('Film strip: rendered to %s in %d ms...', path, Date.now() - now);
+
+		// stats
+		timeTotal += (Date.now() - now);
+		screenshotsTotal++;
+	}
+
+	// bind to events to render screenshots on
+	[
+		'loadStarted',
+		'send',
+		'recv',
+		'loadFinished',
+		'report'
+	].forEach(function(ev) {
+		phantomas.on(ev, screenshot);
+	});
+
+	// print-out stats
+	phantomas.on('report', function() {
+		phantomas.log('Film strip: spent %d ms on rendering %d screenshots', timeTotal, screenshotsTotal);
+	});
+};