Update details.

Signed-off-by: Benjamin Perseghetti <bperseghetti@rudislabs.com>

include/gz/math/Cone.hh

@@ -40,8 +40,9 @@ namespace gz
     /// The cone class supports defining a cone with a radius,
     /// length, rotational offset, and material properties. Radius and
     /// length are in meters. See Material for more on material properties.
-    /// By default, a cone's length is aligned with the Z axis. The
-    /// rotational offset encodes a rotation from the z axis.
+    /// By default, a cone's length is aligned with the Z axis where the base
+    /// of the cone is proximal to the origin and vertex points in positive Z.
+    /// The rotational offset encodes a rotation from the z axis.
     template<typename Precision>
     class Cone
     {