A region of an extrusion's (or revolution's) cross-section that no
structured scheme fits is now cut by straight lines into blocks that fit,
before interval assignment, so the cuts are curves of the arrangement and
their counts are assigned with the rest; nothing reaches the model
(hex::decompose, after Tam and Armstrong's medial-axis subdivision and Li,
Armstrong and McKeag's primitives).
Per region: several holes are separated by lines across the gaps between
neighbouring holes; a piece with one hole gets the O-grid layout whose
pieces score best (lines from the outer corners towards the hole or along
their bisectors, from the hole's corners, or along four directions from
the hole); pieces without holes are cut by a two-ply search over lines
from concave corners and fillets and from convex corners. Candidates are
scored by meshing the pieces with their schemes (smallest corner scaled
Jacobian). A region's blocks are kept when fair (at least 0.5) or no worse
than its free mesh, and cuts never end inside a seeded curve.
This replaces the cuts from reflex corners along an edge. Tests on an L,
a T, a plate with a hole, with a slot and with three holes, and the half
crank's cross-section: every region structured, the quads conforming and
the smallest corner scaled Jacobian bounded. The half crank arm now
extrudes in 12 structured regions with a hex20 minimum scaled Jacobian of
0.37 (the arm meeting the bosses 20 degrees off tangent bounds it) where
it had 2 free regions and 0.009.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo
A cross-section region with three corners (a fillet's quarter disk, a
pocket corner cut off by a partition) was left to the free all-quad
mesher. It now gets midpoint subdivision's triangle primitive (Tam and
Armstrong 1991; Li, Armstrong, McKeag 1997): lines from a centre to a
node on each side split it into three mapped blocks, the interior then
smoothed and every quadrilateral checked (a fold falls back to free).
Interval assignment gains dominance constraints (a side shorter than
the other two together) so the split always exists.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01UhhZMBTviDQxZvwnyP89fo
The end-to-end demo met a raw-CDT sliver that the validity gate accepted (exactly positive) and
the solver refused. Now:
- One validity criterion, `fieldcraft_model::admissible_jacobian` (normalized Jacobian above
1e-12), used by the implicit solver (fem `positive_inverse`), the explicit tet4/hex8
kinematics and the mesh gate, which proves it on the whole element (tet4: the solvers' own
Jacobian; curved kinds: a Bernstein floor), so whatever passes the gate passes the solvers.
- CDT rounding repaired by flips on the rounded mesh (Diazzi et al. 2023 §5.1) instead of the
±2-ulp nudge.
- `fieldcraft-mesh::tet`: a mutable tetrahedral complex whose every change is a checked
replacement (positive and admissible tetrahedra, faces matched with opposite orientation) with
an exact undo log; edge removal (Klincsek), multi-face removal, Delaunay insertion with
boundary faces, edge collapse; a curvature- and thickness-graded size field; constrained
Delaunay refinement with encroachment splits; ODT smoothing; the Klingner–Shewchuk schedule;
boundary vertices moved onto the exact B-rep surfaces at the end; tet10 with mid-edge nodes on
the geometry.
- `mesh.tet.generate` gains size, order, quality, quality_target, curvature_angle, grading,
max_passes, max_points and reports the CDT's and the mesh's quality; `solve.probe` takes a set
and reports its largest von Mises stress.
- Oracle cases filleted-bracket-fillet-stress(-coarse): the fillet's peak von Mises stress on
tet10 meshes of 2k and 13.5k elements, 213.3 MPa (a four-level study stays within 1.8%); the
CDT cases keep the raw tetrahedralization.
- Corpus quality columns: all 20 valid parts mesh and pass the gate.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
The corpus runs mesh.hex.octree's mesher on every part at 1/25 of its diagonal (the size of
the structured hex column) and reports hexahedra, the smallest and mean scaled Jacobian, the
mesh volume against SolidCraft's and the time; a part it cannot mesh gets the reason. The
column caps the elements at 500 000 so a part whose grid explodes is refused in seconds.
Loaded parts carry their bounding-box diagonal for the stages. docs/meshing/corpus.md
regenerated: 15 of 21 parts mesh, including filleted-bracket, rounded-box, sphere-on-plate
and the analytic sphere.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
`fieldcraft_mesh::octree::octree_hex_mesh` meshes any closed part with hex8 only:
- an adaptive 3-refinement grid (27-tree) with strong balance and closure, filled with
conforming node-marking transition templates (Schneiders; checked over all 48 symmetries);
- a core of grid cells kept clear of the boundary (the HybridOctree buffer rule), with
non-manifold cleanup and a genus check against the part;
- a feature graph from the B-rep (corners, curves, patches) and a partition-first map of the
core's boundary onto it, then two boundary layers: a padding layer and a pillow per patch,
so every face boundary and sharp edge is captured by element edges;
- a Garanzha-type untangling and fitting energy (shape term |J|^3/chi, a volume term and a
soft fitting term, deterministic across platforms), a compass search on the worst
elements and a certified repair; failures refine the grid near them and rebuild, within
bounded attempts and growth.
The output passes the certified Jacobian check of every element and a gate that the
boundary encloses the elements' volume; boundary quads carry their B-rep faces. Quality is
reported with the same scaled Jacobian as mesh.quality. Literature notes for each step are in
docs/meshing/literature.md (B1.6-B1.10).
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
filleted-bracket-blocks splits the bracket with SolidCraft's Split Body
into three slabs across its width, the fillet corner halved along its
diagonal and a four-cell O-grid round each hole; the corpus runner meshes
partitioned parts as one conforming block mesh. A heavy test clamps the
upright, loads the foot and checks hex8 and hex20 converge (hex20 tip
deflection within 0.1 % of a fine tet10 solution). Roadmap M5:
conforming interfaces done.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
hex_mesh_cells meshes cells that meet face to face (SolidCraft split
bodies) as one conforming all-hex mesh: each cell a mapped block after
smoothly meeting faces are joined (virtual topology: the halves of a hole,
a plane running into a fillet), vertices, edges and faces shared by
identity, interval assignment over all cells, each shared face meshed
once, radial edges graded off curved faces. finish spans several cells:
tags per cell, hex20 mid-edge nodes shared across cells, a closed
2-manifold boundary and no free internal face.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
The demo used the corpus I-beam, which is extruded along z and so stood
upright. A new corpus part, cantilever-i-beam, is the same section on the
YZ plane extruded along x, web upright: a sweep along a horizontal axis
for the meshers, and a cantilever that bends downward on screen. The
i-beam part is unchanged (its corpus row and the meshing tests keep it).
The demo clamps it at x = 0 and loads the free end with 1000 N in -z
through a kinematic coupling, and now checks the solution against beam
theory and stops when it is off: tip deflection (bending plus shear)
within 3 %, root bending stress (stress_xx along the top flange,
extrapolated to the root, nodes from the Abaqus deck) within 2 %.
docs/meshing/corpus.md regenerated with the new part.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
Crates fieldcraft-*, binaries fieldcraft and fieldcraft-cli, the .fieldcraft file (format tag
fieldcraft/1, manifest fieldcraft.json), FIELDCRAFT_* environment variables, the MCP server
name, egui widget ids (fc_*), the app icon document FieldCraft.icon and its generated family,
docs and licences. No compatibility shim: no files of the earlier name exist.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Structured hex meshing: multi-level extrude and revolve, one-to-one sweep, mapped blocks (M5)
modelcraft_mesh::hex::hex_mesh meshes a face-tagged boundary surface with
hexahedra by the first structured method that fits: a straight or
rotational multi-level sweep (imprinted cross-section arrangement, cuts at
reflex corners, mapped/annulus/free regions), a one-to-one sweep through
rings of linking faces (least-squares affine layers with residual
correction), or a mapped logical cube (trivariate transfinite
interpolation). Interval assignment couples shared curves; boundary quads
carry B-rep face tags; the certified validity gate, a tiling check and a
fidelity check guard the output; hex20 mid-edge nodes go onto the faces.
Shape::face_surfaces exposes the analytic face surfaces; the corpus runner
gets a structured hex column.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* mesh.hex.generate: structured hex meshing as a command
Meshes one body, every body of the open design or an imported surface,
replaces the mesh, tags element faces with the B-rep faces (so sets by
geometry resolve) and reports per body the method, counts and quality.
The quality pass certifies each element once and feeds the validity gate
(quality::validity_gate_checks). Shape::size gives the cached body size
for defaults instead of a full measure.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Hex: disk O-grids, convex interval cost, early size guard, hex20 corpus column
Smooth single-loop sections (cylinders, tori, vases) get a butterfly O-grid
instead of the free mesher; interval assignment raises counts by the
squared relative error so equal sides share increments evenly; a mesh far
beyond the element limit is refused before any work and mapped limits are
no longer swallowed. The corpus reports hex8 and hex20 quality.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Catalogue: structured hex commands ready (mesh.hex.sweep, mesh.hex.mapped, mesh.hex.generate)
mesh.hex.sweep and mesh.hex.mapped run mesh.hex.generate with the sweeping
methods or the mapped one; mesh.hex.generate is the sweep entry's related
command. The planned M6 octree entry moves to mesh.hex.octree (its icon
renamed with it). docs/features.md regenerated.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Docs: structured hex literature (B8), architecture, roadmap, parity; corpus hex column
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Hex: simplify review fixes
Prepare each sweep frame's cross-section once (arrangement, cuts, fill)
and reuse it across refinement retries; candidate frames come from one
setup pass. Edge triangles come from the feature edges, layer counts go
through size::edge_divisions, sweep residual weights are computed once
per node, flux shape functions live on the stack, and the arrangement's
exact side test and distances serve the region probe. The engine takes
the boundary options mesh.tet.generate takes and names unnamed faces by
index like it; the corpus hex20 run reuses the winning method; the
mapped entry lists mesh.hex.generate too; the octree icon is redrawn
under its new id.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md and docs/meshing/corpus.md after rebasing
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md and docs/meshing/corpus.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md and docs/meshing/corpus.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md and docs/meshing/corpus.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* Regenerate docs/features.md after rebasing onto main
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
---------
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
Survey of ~40 papers for meshing curved B-rep faces for shells: frontal-Delaunay point placement in
the cross-field metric (Remacle et al. 2013), recombination to all-quad, cleanup (Reberol et al.
2021), global parity by minimum T-join, verification on shell benchmarks; licences of every code
base. Also fixes the Lee & Lo 1994 author initials in literature.md B7.2.
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
Model: planar section kinds with Extent, element edges in sets, edge-weighted 2D loads,
centrifugal load, 2D model checks. fem: Plane kernels on Basis::{Tri3,Tri6,Quad4,Quad8}
declaring ElementDofs::new(DofSet::PLANE); QM6 incompatible modes with the
Wilson-Ibrahimbegovic correction. Solver: Kernel enum on the DofLayout; 3D results
bit-identical (hash-checked). Decks: Abaqus CPS/CPE/CAX, Nastran membranes and RFORCE,
LS-DYNA ELFORM 12/13. Mesh: free triangle mesher, planar region meshing, face boundaries.
Engine: mesh.planar with tagged edges. Analytic verification suite in solver/tests/plane.rs.
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
* mesh: boundary surface preparation (weld, manifold and orientation checks, exact self-intersection, feature edges)
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* engine: mesh.surface.check on an open design's body or an imported surface
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* engine: struct-init the test session
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* surface: weld at an absolute distance too; the engine welds CAD tessellations at twice SolidCraft's linear tolerance
Faces of a SolidCraft tessellation carry their own copies of shared boundary points, which agree
only to within the kernel's tolerance (up to ~2e-6 mm on the test corpus).
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* docs: surface preparation in the literature survey, architecture and roadmap
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* surface: simplify after review
- The weld distance travels with the mesh (SurfaceMesh::weld_distance, set by Shape::tessellate),
so every consumer welds a tessellation correctly without opting in.
- Exact tests are infallible on predicates::orient2d_projected (shared with generic_orient2d), and
compute each vertex's plane side once per pair with an early reject.
- One Box3 for the weld, the BVH and shells; a Half struct for edges; the weld's two lookups share
one loop, with chained grid cells; cached normals for feature edges; shared parameter helpers.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* corpus: boundary surface preparation as a corpus stage
20 of 21 parts are valid boundaries with their expected genus; cross-cylinders' tessellation has
cracks and flipped triangles where its two intersection curves meet.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
---------
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
* mesh: element quality metrics and a certified Jacobian validity check
Bernstein-form Jacobian determinants for tet4/tet10/wedge6/hex8/hex20, certified
by bounds and subdivision (Johnen-Remacle-Geuzaine 2013); Shewchuk 2002 tet
metrics, Knupp 2001 hex/wedge/quad metrics; quality report and the validity
gate meshers run on their output.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* engine: mesh.quality command; model documents its node order
mesh.quality reports certified validity, volume and per-metric statistics with
fixed-range histograms. The model's ElementKind doc states the Abaqus/VTK node
order and that deck code reorders formats like Nastran CHEXA20.
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
* quality: simplify after review; exact orient3d for tet4; gate on raw mesher arrays
- tet4 validity from the exact orient3d of the input coordinates
- validity_gate_elements takes (label, kind, coordinates) straight from a mesher
- one Jacobian per solid; certify caches piece bounds; product weights precomputed
- model::check_coordinates shared by set_node and quality; ElementKind is Ord
- engine: shared labels() parameter parser
Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
---------
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
Survey of about 75 papers on robust predicates, Delaunay tetrahedralization, boundary
recovery, quality improvement and hexahedral meshing, with verified DOIs and the
licence of every associated code base. Architecture and roadmap now name the chosen
methods (robust CDT after Diazzi et al. 2023; octree-dual all-hex first). ADR 0001
adds the licence findings and the test-geometry rule.
Claude-Session: https://claude.ai/code/session_01NmAttHhUZTokgPeEJia8sm
Co-authored-by: jyviko <[email protected]>
Co-authored-by: Claude Opus 5.5 <[email protected]>
