For structured domains and unstructured domains used in a prism block the orthogonality of grid points adjacent to the domain is calculated. This function is
intended to assist those building viscous grids since it provides near wall orthogonality in a very accessible manner.
The orthogonality function is a measure of the minimum angle between the line formed by a point on the domain and the first point on the interior of the
associated block and the surface of the domain. The maximum value or perfect orthogonality is 90 degrees. The minimum value is 0 degrees. For this function
the probe will render the point-to-point cell edge as well as the surface points/edges being used to calculate the angle relative to the boundary domain. Of
course, the corresponding value will be labeled on the color bar.
Unstructured domains not in a prism block, structured domains in an unstructured block, and structured domains bounding a prism block have all values set to
zero (0) for this function.