Smooth operator options listed instead of paragraph
@@ -30,6 +30,55 @@ peaks in the mesh while still smoothing out most of the mesh. The angle in the
**Feature Angle** text field determines which features are kept. Any mesh
angles less than the feature angle are preserved while others are smoothed.
+The Smooth Operator applies Laplacian Smoothing to a mesh, making the cells
+better shaped and the nodes more evenly distributed. Each node is moved
+towards a coordinate that is the average of its connected nodes. The
+**relaxation factor** determines how far along that path to move the node. A
+sweep over all nodes is a single iteration. The Smooth operator has a number of
+controls that can be used to tune mesh smoothness.
+
+Maximum number of iterations
+ Controls the maximum number of times the mesh relaxation algorithm is
+ applied to the input mesh. Larger numbers of iterations will produce
+ smoother meshes but will also take more time to compute. Values must be
+ integers.
+
+Relaxation Factor
+ Controls how much the mesh is relaxed. Values near 1 produce a mesh that is
+ very smooth relative to the input mesh. Values must be floating point
+ numbers between 0 and 1.
+
+Convergence
+ Limit the maximum point motion. The smoothing process will terminate if the
+ maximum point motion during an iteration is less than this value. Smaller
+ numbers result in more iterations, and if 0 is supplied then the Smooth
+ operator will perform **Maximum number of iterations**. Values must be
+ floating point numbers between 0 and 1.
+
+Maintain Features
+ When the surface angle between two zones sharing an edge is greater than
+ **Feature Angle**, then the edge is classified as a *feature edge*. The
+ nodes in the mesh are then classified as *simple* (not used by a feature
+ edge), *interior edge* (used by exactly two feature edges), or *fixed* (all
+ other nodes). *Simple* nodes are smoothed as before, *fixed* nodes are not
+ smoothed at all, and *interior edge* nodes are only smoothed along the two
+ connected *feature edges*, and only if the angle between the edges is less
+ than **Max Angle Edge**. This distinction allows the smoothing operation to
+ preserve sharp peaks in the mesh while still smoothing out
+ most of the mesh.
+
+Feature Angle
+ Used to determine the number of feature edges for each node. Values must be
+ floating point numbers between 0 and 90.
+
+Max Angle Edge
+ Used to determine if *interior edge* nodes will be smoothed. Values must be
+ floating point numbers between 0 and 90.
+
+Smooth Along Boundaries
+ Enable the smoothing operation on nodes that are along the boundaries of
+ the mesh.
+
.. _smoothwindow:
.. figure:: images/smoothwindow.png
