forked from 1b-agent/fieldcraft-upstream
85ba526663
* mesh: one transfinite interpolation for mapped hex and mesh.block; stable oracle report mesh.block's lattice is now built from the structured hex mesher's transfinite code: faces by quad::transfinite_grid, the interior by the new quad::transfinite_volume (Gordon-Thiel, blended by the block's graded parameters), which hex::mapped now calls too. 2D patches are the transfinite_grid of their sides. Edge curves return their corners exactly. Oracle: a zero-reference quantity (rounding noise) keeps its absolute tolerance as its fixture band, and docs/oracle.md shows such noise and relative errors inside the fixture band as bounds, so the report no longer changes with the order of floating-point operations (it failed the 'docs/oracle.md is current' check on main after #50). Scordelis-Lo moved by 1.4e-9 relative (an ill-conditioned thin shell of solids: sub-ulp node changes) and is re-blessed. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm * simplify: shared face filling and lattice index; faces blended like the volume; exact ends for every edge quad::transfinite_faces fills a block's six faces (with a per-face hook that hex::mapped uses to project onto its B-rep faces) and quad::lattice_index fixes the lattice layout for all three users. transfinite_grid_blended blends faces by the block's graded parameters, so faces and interior use one parametrisation and mesh.block reproduces its earlier Gordon-Hall lattice (the Scordelis-Lo fixture is back to its blessed value). Straight edges also return their corners exactly. Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm --------- Co-authored-by: jyviko <2501648+jyviko@users.noreply.github.com> Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Constant-stress patch test, hex8
A unit cube of eight hex8 cells whose shared points are moved off the regular grid (every face, edge and centre point; the corners stay), so every element is distorted (one mesh.block per cell). Symmetry on the faces x = 0, y = 0 and z = 0; tractions 1, 2 and 3 on the faces x = 1, y = 1 and z = 1 (E = 1000, ν = 0.25). The exact solution is the uniform stress diag(1, 2, 3) with strains ε_i = (σ_i − ν(σ_j + σ_k))/E, which every conforming element of a convergent formulation reproduces exactly on any mesh.