From a683493e59325137f1c9654d84c3f5a333b69e4a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ju=CC=88rg=20Lehni?= <juerg@scratchdisk.com>
Date: Sun, 4 Jan 2015 14:01:32 +0100
Subject: [PATCH] Implement unit tests for path intersection.

Related: #565, #568, #570, #571
---
 test/tests/Path_Intersections.js | 100 +++++++++++++++++++++++++++++++
 test/tests/load.js               |   1 +
 2 files changed, 101 insertions(+)
 create mode 100644 test/tests/Path_Intersections.js

diff --git a/test/tests/Path_Intersections.js b/test/tests/Path_Intersections.js
new file mode 100644
index 00000000..a8655e8c
--- /dev/null
+++ b/test/tests/Path_Intersections.js
@@ -0,0 +1,100 @@
+/*
+ * Paper.js - The Swiss Army Knife of Vector Graphics Scripting.
+ * http://paperjs.org/
+ *
+ * Copyright (c) 2011 - 2014, Juerg Lehni & Jonathan Puckey
+ * http://scratchdisk.com/ & http://jonathanpuckey.com/
+ *
+ * Distributed under the MIT license. See LICENSE file for details.
+ *
+ * All rights reserved.
+ */
+
+module('Path Intersections');
+
+function testIntersection(intersections, results) {
+    equals(intersections.length, results.length, 'intersections.length');
+    for (var i = 0; i < results.length; i++) {
+        var inter = intersections[i];
+        var values = results[i];
+        var name = 'intersections[' + i + ']';
+        equals(inter.point, new Point(values.point), name + '.point');
+        equals(inter.index, values.index, name + '.index');
+        equals(inter.parameter, values.parameter || 0, name + '.parameter');
+    }
+}
+
+test('path.getIntersections(); #565', function() {
+    // https://github.com/paperjs/paper.js/issues/565
+    var crv1 =  new Curve(new Point(421.75945, 416.40481), new Point(-181.49299, -224.94946), new Point(44.52004, -194.13319), new Point(397.47615, 331.34712));
+    var crv2 =  new Curve(new Point(360.09446, 350.97254), new Point(-58.58867, -218.45806), new Point(-109.55091, -220.99561), new Point(527.83582, 416.79948));
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 354.13635, y: 220.81369 }, index: 0, parameter: 0.46725 },
+        { point: { x: 390.24772, y: 224.27351 }, index: 0, parameter: 0.71605 }
+    ]);
+
+    // Alternative pair of curves that has the same issue
+    var crv1 = new Curve(new Point(484.9026237381622, 404.11001967731863), new Point(-265.1185871567577, -204.00749347172678), new Point(-176.7118886578828, 111.96015905588865), new Point(438.8191690435633, 429.0297837462276));
+    var crv2 = new Curve(new Point(388.25280445162207, 490.95032326877117), new Point(-194.0586572047323, -50.77360603027046), new Point(-184.71034923568368, -260.5346686206758), new Point(498.41401199810207, 455.55853731930256)); var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 335.62744, y: 338.15939 }, index: 0, parameter: 0.26516 }
+    ]);
+});
+
+test('path.getIntersections(); #568', function() {
+    // https://github.com/paperjs/paper.js/issues/568
+    var crv1 = new Curve(new Point(509.05465863179415, 440.1211663847789), new Point(233.6728838738054, -245.8216403145343), new Point(-270.755685120821, 53.14275110140443), new Point(514.079892472364, 481.95262297522277));
+    var crv2 = new Curve(new Point(542.1666181180626, 451.06309361290187), new Point(179.91238399408758, 148.68241581134498), new Point(193.42650789767504, -47.97609066590667), new Point(423.66228222381324, 386.3876062911004));
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 547.96568, y: 396.66339 }, index: 0, parameter: 0.07024 },
+        { point: { x: 504.79973, y: 383.37886 }, index: 0, parameter: 0.48077 }
+    ]);
+
+    var crv1 = new Curve(new Point(0, 0), new Point(20, 40) , new Point (-30, -50), new Point(50, 50));
+    var crv2 = new Curve(new Point(50, 50), new Point(20, 100), new Point (-30, -120), new Point(250, 250));
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 50, y: 50 }, index: 0, parameter: 1 }
+    ]);
+});
+
+test('path.getIntersections(); #570', function() {
+    // https://github.com/paperjs/paper.js/issues/570
+    var crv1 = new Curve(new Point(171, 359), new Point(65.26926656546078, 62.85188632229557), new Point(-37.43795644844329, 7.813022000754188), new Point(311.16034791674826, 406.2985255840872));
+    var crv2 = new Curve(new Point(311.16034791674826, 406.2985255840872), new Point(39.997020018940304, -8.347079462067768), new Point(-73.86292504547487, -77.47859270504358), new Point(465, 467));
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    var ints = crv1.getIntersections(crv2);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 311.16035, y: 406.29853 }, index: 0, parameter: 1 }
+    ]);
+});
+
+test('path.getIntersections(); #571', function() {
+    // https://github.com/paperjs/paper.js/issues/571
+    var crv1 = new Curve(new Point(171, 359),  new Point(205.3908899553486, -14.994581100305595), new Point(5.767644819815757, 28.49094950835297), new Point(420.1235851920127, 275.8351912321666));
+    var crv2 = new Curve(new Point(420.1235851920127, 275.8351912321666), new Point(-10.77224553077383, -53.21262197949682), new Point(-259.2129470250785, -258.56165821345775), new Point(465, 467));
+    var pth1 = new Path([crv1.segment1, crv1.segment2]);
+    var pth2 = new Path([crv2.segment1, crv2.segment2]);
+    testIntersection(crv1.getIntersections(crv2), [
+        { point: { x: 352.39945, y: 330.44135 }, index: 0, parameter: 0.41159 },
+        { point: { x: 420.12359, y: 275.83519 }, index: 0, parameter: 1 }
+    ]);
+});
+
+
+test('path.getIntersections(); overlapping circles', function() {
+    var c1 = new Path.Circle(new paper.Point(50, 50), 50);
+    var c2 = new Path.Circle(new paper.Point(100, 100), 50);
+    testIntersection(c1.getIntersections(c2), [
+        { point: { x: 100, y: 50 }, index: 2 },
+        { point: { x: 50, y: 100 }, index: 3 }
+    ]);
+});
diff --git a/test/tests/load.js b/test/tests/load.js
index 68c87ecd..7fb01db5 100644
--- a/test/tests/load.js
+++ b/test/tests/load.js
@@ -35,6 +35,7 @@
 /*#*/ include('Path_Curves.js');
 /*#*/ include('Path_Bounds.js');
 /*#*/ include('Path_Length.js');
+/*#*/ include('Path_Intersections.js');
 
 /*#*/ include('Curve.js');
 /*#*/ include('CurveLocation.js');