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diff --git a/src/vector.cpp b/src/vector.cpp
index a60c133..20b8ef5 100644
--- a/src/vector.cpp
+++ b/src/vector.cpp
@@ -194,7 +194,8 @@ Vector Vector::Unit(void)
 {
 	double mag = Magnitude();
 
-	// If the magnitude of the vector is zero, then the Unit vector is undefined...
+	// If the magnitude of the vector is zero, then the Unit vector is
+	// undefined...
 	if (mag == 0)
 		return Vector(0, 0, 0);
 
@@ -210,11 +211,11 @@ double Vector::Magnitude(void)
 
 double Vector::Angle(void)
 {
-	// acos returns a value between zero and PI, which means we don't know which
-	// quadrant the angle is in... Though, if the y-coordinate of the vector is
-	// negative, that means that the angle is in quadrants III - IV.
+	// acos returns a value between zero and TAU/2, which means we don't know
+	// which quadrant the angle is in... However, if the y-coordinate of the
+	// vector is negative, that means that the angle is in quadrants III - IV.
 	double rawAngle = acos(Unit().x);
-	double correctedAngle = (y < 0 ? (2.0 * PI) - rawAngle : rawAngle);
+	double correctedAngle = (y < 0 ? TAU - rawAngle : rawAngle);
 
 	return correctedAngle;
 }
@@ -243,6 +244,15 @@ bool Vector::isZero(double epsilon/*= 1e-6*/)
 }
 
 
+//
+// Convenience function
+//
+/*static*/ double Vector::Angle(Point p1, Point p2)
+{
+	return Vector(p1, p2).Angle();
+}
+
+
 // Returns the parameter of a point in space to this vector. If the parameter
 // is between 0 and 1, the normal of the vector to the point is on the vector.
 // Note: v1 is the tail, v2 is the head of the line (vector).
@@ -276,10 +286,10 @@ bool Vector::isZero(double epsilon/*= 1e-6*/)
 	// This is done using the following formula:
 	// (a . b) = ||a|| ||b|| cos(theta)
 	// However, have to check for two degenerate cases, where a = cb:
-	// 1, if c > 0, theta = 0; 2, if c < 0, theta = 180°.
+	// 1) if c > 0, theta = 0; 2) if c < 0, theta = 180°.
 	// Also, the vectors a & b have to be non-zero.
 	// Also, have to check using an epsilon because acos will not return an
-	// exact value if the vectors are orthogonal
+	// exact value if the vectors are orthogonal.
 	if (a.isZero() || b.isZero())
 		return 0;