Major revision of ADR-002 based on implementation experience.
Decision change:
- OLD (Nov 9): Topology without node count (pure geometry)
- NEW (Nov 13): Topology with node count type parameter
Rationale:
Node count comes from MESH FILES, not from basis choice. When reading
Abaqus .inp, Code Aster .med, or GMSH .msh files, the mesh explicitly
specifies node count in element connectivity:
- Hex element (1,2,...,8) → 8 nodes
- Hex element (1,2,...,20) → 20 nodes
- Hex element (1,2,...,27) → 27 nodes
The mesh reader knows node count BEFORE basis functions are selected.
Therefore, topology must include node count: Hexahedron{N}.
New design:
struct Hexahedron{N} <: AbstractTopology end
const Hex8 = Hexahedron{8}
const Hex20 = Hexahedron{20}
This maintains type stability (N known at compile time) while
acknowledging that N originates from mesh data, not basis choice.
Supersedes: ADR-002 (November 9, 2025)
- 4 design documents for GPU implementation (2588 lines total)
- gpu_physics_architecture.md: Physics{Elasticity} GPU-first design
- gpu_cpu_backend_architecture.md: Backend selection and dispatch
- gpu_cpu_migration_guide.md: Migration from old API to new
- gpu_elasticity_refactoring.md: Complete refactoring strategy
- Zero CPU-GPU transfer during solve, matrix-free CG
- Elements store geometry, no mesh dependency
- Breaking changes allowed for GPU performance
- Relocate docs/blog/immutability_performance.md to docs/src/book/blog/
- Comprehensive guide on immutable material models with Tensors.jl
- Covers LinearElastic, NeoHookean, PerfectPlasticity implementations
- Includes full benchmarks: 5× speedup for linear, 21× for plasticity
- Zero allocation performance validated
- Part of three-tier docs reorganization under standard docs/src/ structure
- Relocate docs/book/README.md to docs/src/book/README.md
- Follows standard Julia documentation structure where all source files live under docs/src/
- File contains YAML header and book philosophy/structure overview
- Part of three-tier documentation reorganization (user/contributor/book)
Jukka Aho