From d8f54b1c9b6539ed993aead2cb2dea50f72d14f4 Mon Sep 17 00:00:00 2001
From: Jonathan Puckey <me@jonathanpuckey.com>
Date: Thu, 30 Jun 2011 13:55:35 +0200
Subject: [PATCH] Add FutureSplash example.

---
 examples/Animated/FutureSplash.html | 143 ++++++++++++++++++++++++++++
 1 file changed, 143 insertions(+)
 create mode 100644 examples/Animated/FutureSplash.html
diff --git a/examples/Animated/FutureSplash.html b/examples/Animated/FutureSplash.html
new file mode 100644
index 00000000..71993618
--- /dev/null
+++ b/examples/Animated/FutureSplash.html
@@ -0,0 +1,143 @@
+<!DOCTYPE html>
+<html>
+<head>
+	<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
+	<title>Example</title>
+	<link rel="stylesheet" href="../css/style.css">
+	<script type="text/javascript" src="../../dist/paper.js"></script>
+	<script type="text/paperscript" canvas="canvas">
+		// Code ported to Paper.js from http://the389.com/9/1/
+		// with permission.
+
+		var values = {
+			friction: 0.8,
+			timeStep: 0.01,
+			amount: 15,
+			mass: 2,
+			count: 0
+		};
+		values.invMass = 1 / values.mass;
+
+		var path;
+		var size = view.size * [1.2, 1];
+
+		var Spring = Base.extend({
+			initialize: function(a, b, param) {
+				if (!param)
+					param = {};
+				this.a = a;
+				this.b = b;
+				this.restLength = param.restLength || 80;
+				this.strength = param.strength ? param.strength : 0.55;
+				this.mamb = values.invMass * values.invMass;
+			},
+
+			update: function() {
+				var delta = this.b - this.a;
+				var dist = delta.length;
+				var normDistStrength = (dist - this.restLength) /
+						(dist * (this.mamb)) * this.strength;
+				delta.y *= (normDistStrength * values.invMass) / 5;
+				if (!this.a.fixed)
+					this.a.y += delta.y;
+				if (!this.b.fixed)
+					this.b.y -= delta.y;
+			}
+		});
+
+		onResize();
+
+		function onResize() {
+			values.count = 0;
+			if (path) {
+				path.remove();
+			}
+			size = view.bounds.size * [2, 1];
+			path = createPath(0.1);
+		}
+
+		function createPath(strength) {
+			var path = new Path();
+			path.data = {};
+			path.data.springs = [];
+			path.fillColor = 'black';
+			segments = path.segments;
+			var previous;
+			for (var i = 0; i <= values.amount; i++) {
+				var segment = path.add(new Point(i / values.amount, 0.5) * size);
+				var point = segment.point;
+				point.px = point.x;
+				point.py = point.y;
+				point.fixed = i === 0 || i == values.amount;
+				if (previous) {
+					var spring = new Spring(previous, point, {
+						strength: strength
+					});
+					path.data.springs.push(spring);
+				}
+				previous = point;
+			}
+			path.position.x -= size.width / 4;
+			return path;
+		}
+
+		function onMouseMove(event) {
+			var segments = path.segments;
+			var index = Math.floor((event.point.x + size.width / 4)
+					* segments.length / size.width);
+			var y = event.point.y;
+			var range = size.height / 4;
+			var segment = segments[index];
+			var point = segment.point;
+			var prev, next;
+			if (segment.previous)
+				prev = segment.previous.point;
+			if (segment.next)
+				next = segment.next.point;
+
+			if (!point.fixed && y + range > point.y && y - range < point.y) {
+				point.y += (y - point.y) / 6;
+				if (prev && !prev.fixed) prev.y += (y - prev.y) / 12;
+				if (next && !next.fixed) next.y += (y - next.y) / 12;
+			}
+		}
+
+		function onFrame(event) {
+			if (values.count != 0) {
+				path.firstSegment.remove();
+				path.lastSegment.remove();
+			}
+			updateWave(path);
+			values.count++;
+		}
+
+		function updateWave(path) {
+			var segments = path.segments;
+			var force = 1 - values.friction * values.timeStep * values.timeStep;
+			for (var i = 0, l = segments.length; i < l; i++) {
+				var point = segments[i].point;
+				var ty = point.y;
+				var dy = (point.y - point.py) * force;
+				point.y += dy;
+				point.py = ty;
+				point.y = Math.max(0, point.y);
+			}
+
+			for (var j = 0, l = path.data.springs.length; j < l; j++) {
+				path.data.springs[j].update(true);
+			}
+			path.smooth();
+			path.insert(0, new Point(0, size.height));
+			path.add(new Point(size));
+		}
+		
+		function onKeyDown(event) {
+			if (event.key == 'space')
+				path.fullySelected = !path.fullySelected;
+		}
+	</script>
+</head>
+<body>
+	<canvas id="canvas" resize></canvas>
+</body>
+</html>
\ No newline at end of file
