# finite_element_method
A small Rust crate that collects **finite‑element method (FEM) building blocks** used as the
foundation for my browser‑based FEA project [`fea_app`](https://github.com/RomanShushakov/fea_app).
This crate is intentionally **educational and practical**. It focuses on clarity and explicit
data flow (elements → assembly → global system), rather than on being a general‑purpose or
feature‑complete FEM framework.
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## Overview
The goal of this crate is to make the core ideas of the finite‑element method tangible in code:
- how elements are defined and parameterized,
- how local stiffness contributions are assembled,
- how the global system is prepared for downstream solvers.
It is designed to be read, experimented with, and extended.
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## What’s inside
- **Mesh and data model**
- nodes, element connectivity, and basic material / section properties
- **Element implementations**
- a small set of classic structural elements (e.g. truss / beam / plate variants)
- **Assembly helpers**
- routines to compute and assemble global stiffness contributions
- **Geometry utilities**
- small helpers (e.g. planar convex hull) used by element logic
> Solvers live in separate repositories:
>
> - Iterative methods (CG / PCG): [`iterative_solvers`](https://github.com/RomanShushakov/iterative_solvers)
> - Direct solver experiments: [`colsol`](https://github.com/RomanShushakov/colsol)
> - GPU compute & visualization pipeline: implemented in [`fea_app`](https://github.com/RomanShushakov/fea_app)
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## Design notes
- **Readability first**
This code is written to understand FEM internals end‑to‑end, not to hide them behind abstractions.
- **Explicit data flow**
Types and functions aim to make mathematical structure and data movement visible.
- **Scoped ambition**
This is not a production FEM package. It intentionally omits features such as:
nonlinear analysis, contact, advanced integration schemes, or a large element catalog.
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## Documentation
Some background notes and design explanations live in the `docs/` directory:
- [Elements axes direction](./docs/Elements_axes_direction.md)
- [Element types](./docs/Element_types.md)
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## Relationship to `fea_app`
`fea_app` integrates these building blocks into a complete pipeline:
**mesh input → FEM assembly → solver → visualization (WebGL / WebGPU)**
This crate provides the **FEM side** (elements and assembly).
Companion crates provide **solvers** and **GPU compute** experiments.
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## Status
Active learning and exploration.
The API may evolve as the broader project grows.
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## License
MIT OR Apache‑2.0 (see `Cargo.toml`).