more changes based on PR comments

GeoLib/AnalyticalGeometry.h

@@ -131,11 +131,14 @@ bool isPointInTriangle(GeoLib::Point const& p,
 
 /**
  * Tests if the given point p is located within a tetrahedron spanned by points a, b, c, d.
+ * If the tet specified by a, b, c, d is degenerated (i.e. all points are coplanar) the function
+ * will return false because there is no meaningful concept of "inside" for such elements.
  * @param p test point
  * @param a edge node of tetrahedron
  * @param b edge node of tetrahedron
  * @param c edge node of tetrahedron
- * @param c edge node of tetrahedron
+ * @param d edge node of tetrahedron
+ * @param eps Accounts for numerical inaccuracies by allowing a point to be slightly outside of the element and still be regarded as inside.
  * @return true if the test point p is not located outside of abcd (i.e. inside or on a plane/edge).
  */
 bool isPointInTetrahedron(GeoLib::Point const& p, GeoLib::Point const& a, GeoLib::Point const& b, 
@@ -191,8 +194,8 @@ double scalarTriple(MathLib::Vector3 const& u, MathLib::Vector3 const& v, MathLi
  * @param a first point on plane
  * @param b second point on plane
  * @param c third point on plane
- * @return If the triangle abc is ordered counterclockwise when viewed from p, the method will return a value < 0,
- * otherwise it will return > 0. If p is coplanar with abc, the function will return 0.
+ * @return If the triangle abc is ordered counterclockwise when viewed from p, the method will return a negative value,
+ * otherwise it will return a positive value. If p is coplanar with abc, the function will return 0.
  */
 double orient3d(GeoLib::Point const& p,
                 GeoLib::Point const& a, GeoLib::Point const& b, GeoLib::Point const& c);

MeshLib/Elements/Element.cpp

@@ -165,4 +165,3 @@ bool Element::hasNeighbor(Element* elem) const
 
 
 }
-

MeshLib/Elements/Element.h

@@ -161,7 +161,7 @@ public:
 	 * @param eps tolerance for numerical algorithm used or computing the property
 	 * @return true if the point is not outside the element, false otherwise
 	 */
-	virtual bool isPntInElement(GeoLib::Point const& pnt, double eps) const = 0;
+	virtual bool isPntInElement(GeoLib::Point const& pnt, double eps = std::numeric_limits<double>::epsilon()) const = 0;
 
 	/**
 	 * Tests if the element is geometrically valid.

MeshLib/MeshEditing/Mesh2MeshPropertyInterpolation.cpp

@@ -94,7 +94,7 @@ void Mesh2MeshPropertyInterpolation::interpolatePropertiesForMesh(Mesh *dest_mes
 			for (size_t j(0); j<n_nodes_in_vec; j++) {
 				MeshLib::Node const*const j_th_node((*i_th_vec)[j]);
 				if (elem_aabb.containsPoint(*j_th_node)) {
-					if (dest_elements[k]->isPntInElement(* dynamic_cast<GeoLib::Point const*>(j_th_node), 30)) {
+					if (dest_elements[k]->isPntInElement(*j_th_node, 30)) {
 						dest_properties[k] += interpolated_src_node_properties[(*i_th_vec)[j]->getID()];
 						cnt++;
 					}

Tests/MeshLib/TestPntInElement.cpp

@@ -56,6 +56,7 @@ TEST(IsPntInElement, Line)
     ASSERT_EQ(false, line.isPntInElement(pnt));
     deleteNodes(nodes);
 }
+
 TEST(IsPntInElement, Tri)
 {
     GeoLib::Point pnt;