ElemExtrema

Description

ElemExtrema is a helper struct for identifying if a Ray has intersected the "extrema" of an element during tracing. In 2D, an element extrema is defined as a vertex. In 3D, an element extrema is defined as a vertex or an edge.

The intersected element extrema is available in RayKernels and RayBCs during a trace as the _current_intersected_extrema member variable.

The methods of interest for use during tracing on ElemExtrema are:

• atExtrema() - Whether or not the intersection is at an extrema.

• atVertex() - Whether or not the intersection is at a vertex.

• atEdge() - Whether or not the intersection is at an edge.

• vertex() - The local vertex index that was intersected.

• vertexPoint() - The point of the vertex that was intersected.

• edgeVertices() - The vertices that define the edge that was intersected.

• buildEdge() - Builds an Elem that is the edge that was intersected.