forked from 1b-agent/fieldcraft-upstream
e7f5c83b49
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]>
67 lines
4.6 KiB
Markdown
67 lines
4.6 KiB
Markdown
# Architecture
|
||
|
||
ModelCraft turns geometry into finite element models, writes them for the solvers engineers
|
||
already use, and solves linear problems itself.
|
||
|
||
```
|
||
SolidCraft B-rep ──tessellate──▶ boundary surface ──▶ volume mesh ──▶ FE model ──▶ Abaqus .inp
|
||
(solidcraft-kernel) (welded, watertight, tet (Delaunay) materials, Nastran .bdf
|
||
face-tagged) hex (core goal) sections, LS-DYNA .k
|
||
BCs, loads, ──▶ own linear
|
||
steps solver
|
||
```
|
||
|
||
## Crates and layers
|
||
|
||
`cargo xtask layers` enforces the table in `xtask/src/layers.rs`: a crate may depend only on
|
||
crates in strictly lower layers.
|
||
|
||
| Layer | Crate | Role | Status |
|
||
|---|---|---|---|
|
||
| L0 | `modelcraft-model` | Solver-neutral FE model: nodes, elements by label; materials, sections, sets, BCs, loads and steps as they land. Knows no file format. | started |
|
||
| L1 | `modelcraft-geometry` | The only door to SolidCraft: B-rep bodies, measures, tessellation into a face-tagged `SurfaceMesh`. No SolidCraft type in its API. | started |
|
||
| L1 | `modelcraft-mesh` | Surface preparation (weld, watertightness, feature edges), robust predicates, Delaunay tetrahedralization and refinement, Voronoi-based optimization, hex meshing, quality metrics. | planned |
|
||
| L1 | `modelcraft-solver` | Element formulations, assembly, sparse linear static and modal solution. | planned |
|
||
| L1 | `modelcraft-decks` | Abaqus input, Nastran bulk data and LS-DYNA keyword readers and writers, to and from `model`. | planned |
|
||
| L1 | `modelcraft-render` | Display data (meshes, contour maps) without a GPU dependency. | planned |
|
||
| L2 | `modelcraft-doc` | The document: geometry, mesh, model, results, history. | planned |
|
||
| L3 | `modelcraft-io` | `.modelcraft` files, result files. | planned |
|
||
| L4 | `modelcraft-engine` | Commands (`CommandSpec`), `Session::execute` with rollback and the panic guard, scripts. | started |
|
||
| L5 | `modelcraft-ui-egui`, `modelcraft-mcp` | Desktop UI, control channel and MCP server. | planned |
|
||
| apps | `modelcraft`, `modelcraft-cli`, `modelcraft-web` | Desktop, command line, browser. | cli started |
|
||
|
||
Rules beyond the layer order:
|
||
- Nothing below L5 uses egui, eframe, winit, wgpu or rfd.
|
||
- Only `modelcraft-geometry` uses `solidcraft-*`, pinned by rev in the workspace `Cargo.toml`.
|
||
SolidCraft's `[patch.crates-io]` (its fixed truck crates) does not reach dependents, so the
|
||
workspace repeats it from the same rev; bump both together.
|
||
- Everything below the apps builds for `wasm32-unknown-unknown`.
|
||
|
||
## Meshing pipeline
|
||
|
||
1. **Boundary surface.** SolidCraft tessellates each body; every triangle carries its B-rep face,
|
||
so feature edges and face-based loads and BCs survive meshing.
|
||
2. **Surface preparation.** Weld coincident vertices, check the surface is closed, manifold and
|
||
consistently oriented, find feature edges (face boundaries, sharp dihedral angles).
|
||
3. **Tetrahedral meshing.** Bowyer–Watson Delaunay on Shewchuk's adaptive predicates (symbolic
|
||
perturbation for degeneracies), boundary recovery by the robust constrained Delaunay method of
|
||
Diazzi et al. 2023 (implicit Steiner points on indirect predicates, gift-wrapping fallback), so
|
||
every boundary triangle and its B-rep face tag survives. Then constrained Delaunay refinement to a
|
||
size field, ODT smoothing interleaved as in Tournois et al. 2009, and the Klingner–Shewchuk 2007
|
||
improvement schedule against slivers.
|
||
4. **Hexahedral meshing (the core).** Octree/grid dual all-hex first, the one family that meshes
|
||
any input validly (Livesu et al. 2021 dual schemes, Pitzalis et al. 2021 refinement, Gao et al.
|
||
2019 feature projection and padding, Garanzha et al. 2021 untangling). Then hex-dominant by tet
|
||
recombination (Pellerin et al. 2018), then polycube (DualCube labelling) for blocky parts;
|
||
frame-field/integer-grid-map methods stay research. Validity uses a certified trilinear Jacobian
|
||
check (Marschner et al. 2020), not corner Jacobians alone.
|
||
5. **Quality.** Scaled Jacobian, aspect ratio, dihedral angles; every generated mesh is checked
|
||
for positive Jacobians and conserved volume before it reaches the model.
|
||
|
||
## Commands
|
||
|
||
Every user-visible action is a `CommandSpec` in `crates/engine/src/cmd/<area>.rs` with a JSON
|
||
form. `Session::execute` clones the model, runs the command under `catch_unwind`, and restores
|
||
the model on an error or a panic; commands that changed the model are journalled, so the
|
||
journal replays as a script.
|