A five-node pyramid, the conforming transition between a hexahedron's face
and tetrahedra: Bedrosian's rational shape functions with a collapsed (Duffy)
Gauss rule, a certified Jacobian on the base square with exact volume, a
scaled Jacobian, C3D5 / CPYRAM / LS-DYNA degenerate solid, VTK_PYRAMID and
the binary mesh code 13. A distorted hex8-pyramid5-tet4 transition mesh
passes the patch test and uniaxial tension exactly.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo
fieldcraft_mesh::mirror reflects a region's tet4, tet10, wedge6, hex8 and hex20
elements across a plane. The copies list their nodes in reflected order (corners
swapped, mid-side nodes following their edges), so every copy is right-handed;
reflected_faces and reflected_edges give the copy's face and edge over the same
nodes. Copies of the nodes on the plane are merged with the originals through
join::merge_coincident, so the region and its image form one conforming mesh.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo
