Implement Path#getArea() and CompoundPath#getArea().

src/path/Curve.js

@@ -267,6 +267,10 @@ var Curve = this.Curve = Base.extend(/** @lends Curve# */{
 		return length;
 	},
 
+	getArea: function() {
+		return Curve.getArea(this.getValues());
+	},
+
 	getPart: function(from, to) {
 		return new Curve(Curve.getPart(this.getValues(), from, to));
 	},
@@ -986,6 +990,20 @@ new function() { // Scope for methods that require numerical integration
 			return Numerical.integrate(ds, a, b, getIterations(a, b));
 		},
 
+		getArea: function(v) {
+			var p1x = v[0], p1y = v[1],
+				c1x = v[2], c1y = v[3],
+				c2x = v[4], c2y = v[5],
+				p2x = v[6], p2y = v[7];
+			// http://objectmix.com/graphics/133553-area-closed-bezier-curve.html
+			return 3 / 10 * c1y * p1x - 3 / 20 * c1y * c2x
+					- 3 / 20 * c1y * p2x - 3 / 10 * p1y * c1x
+					- 3 / 20 * p1y * c2x - 1 / 20 * p1y * p2x
+					+ 3 / 20 * c2y * p1x + 3 / 20 * c2y * c1x
+					- 3 / 10 * c2y * p2x + 1 / 20 * p2y * p1x
+					+ 3 / 20 * p2y * c1x + 3 / 10 * p2y * c2x;
+		},
+
 		getParameterAt: function(v, offset, start) {
 			if (offset == 0)
 				return start;