Added Rectangle to Triangle, and Triangle to Triangle intersection functions. Detects for face intersection and also point within point (so a triangle fully enclosed inside a rectangle for example)

v3/src/checksum.js

@@ -1,4 +1,4 @@
 var CHECKSUM = {
-build: 'dc876af0-18bc-11e7-88e3-6f7931ffc17c'
+build: 'e1a4b350-18c9-11e7-9368-79f8c4c534b2'
 };
 module.exports = CHECKSUM;

v3/src/geom/intersects/RectangleToTriangle.js

@@ -0,0 +1,60 @@
+
+var LineToLine = require('./LineToLine');
+var Contains = require('../rectangle/Contains');
+var ContainsArray = require('../triangle/ContainsArray');
+var Decompose = require('../rectangle/Decompose');
+
+var RectangleToTriangle = function (rect, triangle)
+{
+    var triA = triangle.getLineA();
+    var triB = triangle.getLineB();
+    var triC = triangle.getLineC();
+
+    //  Are any of the triangle points within the rectangle?
+
+    if (Contains(rect, triA.x1, triA.y1) || Contains(rect, triA.x2, triA.y2))
+    {
+        return true;
+    }
+
+    if (Contains(rect, triB.x1, triA.y1) || Contains(rect, triB.x2, triA.y2))
+    {
+        return true;
+    }
+
+    if (Contains(rect, triC.x1, triA.y1) || Contains(rect, triC.x2, triA.y2))
+    {
+        return true;
+    }
+
+    //  Cheap tests over, no to see if any of the lines intersect ...
+
+    var rectA = rect.getLineA();
+    var rectB = rect.getLineB();
+    var rectC = rect.getLineC();
+    var rectD = rect.getLineD();
+
+    if (LineToLine(triA, rectA) || LineToLine(triA, rectB) || LineToLine(triA, rectC) || LineToLine(triA, rectD))
+    {
+        return true;
+    }
+
+    if (LineToLine(triB, rectA) || LineToLine(triB, rectB) || LineToLine(triB, rectC) || LineToLine(triB, rectD))
+    {
+        return true;
+    }
+
+    if (LineToLine(triC, rectA) || LineToLine(triC, rectB) || LineToLine(triC, rectC) || LineToLine(triC, rectD))
+    {
+        return true;
+    }
+
+    //  None of the lines intersect, so are any rectangle points within the triangle?
+
+    var points = Decompose(rect);
+    var within = ContainsArray(triangle, points, true);
+
+    return (within.length > 0);
+};
+
+module.exports = RectangleToTriangle;

v3/src/geom/intersects/TriangleToTriangle.js

@@ -0,0 +1,55 @@
+
+var LineToLine = require('./LineToLine');
+var ContainsArray = require('../triangle/ContainsArray');
+var Decompose = require('../triangle/Decompose');
+
+var TriangleToTriangle = function (triangleA, triangleB)
+{
+    var lineAA = triangleA.getLineA();
+    var lineAB = triangleA.getLineB();
+    var lineAC = triangleA.getLineC();
+
+    var lineBA = triangleB.getLineA();
+    var lineBB = triangleB.getLineB();
+    var lineBC = triangleB.getLineC();
+
+    //  Now check the lines against each line of TriangleB
+    if (LineToLine(lineAA, lineBA) || LineToLine(lineAA, lineBB) || LineToLine(lineAA, lineBC))
+    {
+        return true;
+    }
+
+    if (LineToLine(lineAB, lineBA) || LineToLine(lineAB, lineBB) || LineToLine(lineAB, lineBC))
+    {
+        return true;
+    }
+
+    if (LineToLine(lineAC, lineBA) || LineToLine(lineAC, lineBB) || LineToLine(lineAC, lineBC))
+    {
+        return true;
+    }
+
+    //  Nope, so check to see if any of the points of triangleA are within triangleB
+
+    var points = Decompose(triangleA);
+    var within = ContainsArray(triangleB, points, true);
+
+    if (within.length > 0)
+    {
+        return true;
+    }
+
+    //  Finally check to see if any of the points of triangleB are within triangleA
+
+    points = Decompose(triangleB);
+    within = ContainsArray(triangleA, points, true);
+
+    if (within.length > 0)
+    {
+        return true;
+    }
+
+    return false;
+};
+
+module.exports = TriangleToTriangle;

v3/src/geom/intersects/index.js

@@ -11,8 +11,10 @@ module.exports = {
     PointToLine: require('./PointToLine'),
     PointToLineSegment: require('./PointToLineSegment'),
     RectangleToRectangle: require('./RectangleToRectangle'),
+    RectangleToTriangle: require('./RectangleToTriangle'),
     RectangleToValues: require('./RectangleToValues'),
     TriangleToCircle: require('./TriangleToCircle'),
-    TriangleToLine: require('./TriangleToLine')
+    TriangleToLine: require('./TriangleToLine'),
+    TriangleToTriangle: require('./TriangleToTriangle')
 
 };

v3/src/geom/rectangle/Rectangle.js

@@ -60,6 +60,30 @@ Rectangle.prototype = {
     isEmpty: function ()
     {
         return (this.width <= 0 || this.height <= 0);
+    },
+
+    //  TOP
+    getLineA: function ()
+    {
+        return { x1: this.x, y1: this.y, x2: this.right, y2: this.y };
+    },
+
+    //  RIGHT
+    getLineB: function ()
+    {
+        return { x1: this.right, y1: this.y, x2: this.right, y2: this.bottom };
+    },
+
+    //  BOTTOM
+    getLineC: function ()
+    {
+        return { x1: this.right, y1: this.bottom, x2: this.x, y2: this.bottom };
+    },
+
+    //  LEFT
+    getLineD: function ()
+    {
+        return { x1: this.x, y1: this.bottom, x2: this.x, y2: this.y };
     }
 
 };