added tests for if ray origin is inside of sphere

test/unit/math/Ray.js

@@ -118,7 +118,7 @@ test( "intersectSphere", function() {
 	var a1 = new THREE.Ray( one3.clone(), new THREE.Vector3( -1, 0, 0 ) );
 
 	// sphere (radius of 2) located behind ray a0, should result in null
-	var b = new THREE.Sphere( new THREE.Vector3( 0, 0, 1 ), 2 );
+	var b = new THREE.Sphere( new THREE.Vector3( 0, 0, 3 ), 2 );
 	ok( a0.intersectSphere( b ) === null, "Passed!" );
 	
 	// sphere (radius of 2) located in front of, but too far right of ray a0, should result in null
@@ -145,12 +145,26 @@ test( "intersectSphere", function() {
 	var b = new THREE.Sphere( new THREE.Vector3( 2.01, 0, -1 ), 2 );
 	ok( a0.intersectSphere( b ) === null, "Passed!" );
 	
+	// following tests are for situations where the ray origin is inside the sphere
+	
 	// sphere (radius of 1) center located at ray a0 origin / sphere surrounds the ray origin, so the first intersect point 0, 0, 1, 
 	// is behind ray a0.  Therefore, second exit point on back of sphere will be returned: 0, 0, -1
 	// thus keeping the intersection point always in front of the ray.
 	var b = new THREE.Sphere( zero3.clone(), 1 );
 	ok( a0.intersectSphere( b ).distanceTo( new THREE.Vector3( 0, 0, -1 ) ) < TOL, "Passed!" );
 	
+	// sphere (radius of 4) center located behind ray a0 origin / sphere surrounds the ray origin, so the first intersect point 0, 0, 5, 
+	// is behind ray a0.  Therefore, second exit point on back of sphere will be returned: 0, 0, -3
+	// thus keeping the intersection point always in front of the ray.
+	var b = new THREE.Sphere( new THREE.Vector3( 0, 0, 1 ), 4 );
+	ok( a0.intersectSphere( b ).distanceTo( new THREE.Vector3( 0, 0, -3 ) ) < TOL, "Passed!" );
+	
+	// sphere (radius of 4) center located in front of ray a0 origin / sphere surrounds the ray origin, so the first intersect point 0, 0, 3, 
+	// is behind ray a0.  Therefore, second exit point on back of sphere will be returned: 0, 0, -5
+	// thus keeping the intersection point always in front of the ray.
+	var b = new THREE.Sphere( new THREE.Vector3( 0, 0, -1 ), 4 );
+	ok( a0.intersectSphere( b ).distanceTo( new THREE.Vector3( 0, 0, -5 ) ) < TOL, "Passed!" );
+	
 });
 
 test( "isIntersectionPlane", function() {