otko/README.md

<p align="center">
  <img src="docs/logo.svg" alt="OTKO" width="640">
</p>

<p align="center">
  A modern, SAP2000-style desktop GUI for
  <a href="https://openseespydoc.readthedocs.io/">OpenSeesPy</a> —
  built for structural and earthquake engineers who want a visual
  modeling environment without leaving the OpenSees ecosystem.
</p>

<p align="center">
  <em>Status: Pre-alpha. Active development. APIs and file formats will change.</em>
</p>

---

![OTKO main window](docs/screenshots/main_window.png)

## Why

OpenSees is the gold-standard nonlinear FEM solver for earthquake
engineering, but its native interface is Tcl/Python scripts.
OTKO adds a visual front-end so you can:

- Click to draw nodes, frames, supports, and loads on a snapped grid.
- Assign materials, sections, and load patterns through dialogs.
- Run static, modal, pushover, and time-history analyses with progress
  and cancel support.
- Inspect results visually — deformed shape, mode shapes, force
  diagrams, pushover curves, time-history plots, hysteresis loops.
- Save the model as a single `.osmodel` JSON file that round-trips
  cleanly (diff-able in Git, scriptable from Python).

Behind the GUI, the same `core` Pydantic model is fully usable from a
script or Jupyter notebook — the GUI is one frontend, not the only one.

## What works today

- **Modeling** — grids, nodes, frames (elastic + force-based), trusses,
  quads, zero-length sections, restraints, equalDOF constraints,
  distributed loads, ground motions (`PathTimeSeries` /
  `UniformExcitation`).
- **Materials and sections** — `Steel01`, `Steel02`, `Concrete01`,
  `Concrete02`, `ElasticPP`, `Hysteretic`, fiber sections (rectangular /
  circular patches + rebar layers), `SectionAggregator`,
  `BeamWithHinges`.
- **Analyses** — static (load- or displacement-controlled), modal,
  displacement-controlled pushover, transient time-history with
  mode-1 Rayleigh damping. Chained workflows: gravity preload →
  `loadConst -time 0.0` → pushover or transient.
- **Post-processing** — deformed shape (with scale slider), animated
  mode shapes, axial / shear / moment diagrams, pushover curves
  (in display units), time-history plots, hysteresis loops,
  response-spectrum SRSS / CQC, snapshot + video export.
- **Persistence** — projects save as a single JSON `.osmodel` file
  (Pydantic-validated, round-trip-clean).
- **Examples** — 20+ verified examples bundled, including the OpenSees
  Wiki Examples-1 through Example-4 family and a fiber-section RC frame
  pushover. See [`examples/README.md`](examples/README.md).

## Tech stack

| Layer        | Library                              |
| ------------ | ------------------------------------ |
| GUI          | PySide6 (Qt 6)                       |
| 3D viewport  | PyVista + pyvistaqt (VTK)            |
| 2D plots     | pyqtgraph                            |
| Solver       | OpenSeesPy 3.8.0.0                   |
| Numerics     | NumPy                                |
| Storage      | Pydantic v2 (model), h5py (results)  |
| Tests        | pytest, pytest-qt                    |
| Lint / type  | ruff, mypy                           |

## Architecture

Strict MVVM + service layer. The `core` package is pure Python — no Qt,
no OpenSeesPy imports — and is fully unit-testable in isolation.

```
views (Qt)  →  viewmodels  →  services (OpenSeesRunner, Persistence)  →  core (model)
```

See [`docs/architecture.md`](docs/architecture.md) for the long form,
including the canonical OpenSeesPy command sequence the runner emits.

## Install (development)

**Desktop GUI** (includes Qt, PyVista, pyqtgraph, imageio):

```bash
git clone https://github.com/ogunc/otko.git
cd otko

python -m venv .venv
.venv\Scripts\activate              # Windows
source .venv/bin/activate           # Linux / macOS

pip install -e ".[gui,dev]"
```

**Headless / web reuse** (core + services only, no Qt pulled in):

```bash
pip install -e .
```

This installs only the headless base set (pydantic, numpy, h5py, openseespy).
It is the correct install for web backends, scripts, and Jupyter notebooks that
reuse `otko.core` or `otko.services` without the GUI.

Python 3.10+ is required. On Windows use **3.12+** — the `openseespywin==3.8.0.0`
wheel has no 3.11 build (`Requires-Python >=3.12`). Pin both
`openseespy==3.8.0.0` and `openseespywin==3.8.0.0` (already pinned
in `pyproject.toml`).

## Quick start — the 60-second tour

```bash
python -m otko
```

Then:

1. **File → Open** → pick `examples/cantilever.osmodel`.
2. **Analyze → Cases** → run `Tip-Load`.
3. **Display → Show Force Diagram** → component **M3** → linear moment
   peaking at 50 kN·m at the fixed end. Component **V2** → constant
   -10 kN.
4. **Display → Show Deformed Shape** → the classic cantilever curve.

For a nonlinear walkthrough, open `examples/portal_pushover.osmodel`,
run the `Push-X` case, then **Display → Show Pushover Curve** — you'll
see the elastic ramp followed by a yield plateau as the fiber-section
hinges form at the column bases.

## Run the test suite

```bash
pytest tests/unit          # pure-logic tests, milliseconds
pytest tests/gui           # Qt event-loop tests (pytest-qt)
pytest tests/integration   # real OpenSeesPy runs on bundled examples
```

CI runs lint + the non-`slow` subset on Linux / macOS / Windows
× Python 3.10 / 3.11 / 3.12.

## Roadmap

See [`docs/roadmap.md`](docs/roadmap.md) for the phase-by-phase plan.
Phases 0–7 (modeling, analysis, post-processing) are largely done.
Phase 8 (earthquake-engineering primitives — isolators, ground-motion
library, IDA, fiber-section editor polish) is the active edge.

## We're looking for collaborators

This project is most useful to researchers and engineers who already
work with OpenSees and want a faster path from "idea" to "model" —
**and who would rather build that path together than alone.**

If any of the following sounds like you, please open an issue or
say hi:

- 🌉 **Structural / earthquake engineers** comfortable with OpenSees Tcl
  or OpenSeesPy who can spot when a feature is "almost right but not
  quite" — that calibration feedback is gold.
- 🧪 **Researchers** running pushover, IDA, or response-spectrum studies
  who want to validate the GUI against their hand-built scripts.
- 🐍 **Python / Qt developers** interested in scientific desktop apps,
  PyVista / VTK rendering, or Pydantic-driven schema design.
- 📚 **Students** who want to learn structural FEM and modern GUI
  architecture at the same time — example walkthroughs and tests are
  designed to read as documentation.
- 🎨 **UX / icon designers** willing to help shape the dialog set,
  toolbar icons, and overall visual language.

Open issues, bug reports, and reproducible test cases are just as
valuable as code. See [`CONTRIBUTING.md`](CONTRIBUTING.md) for the dev
setup and the architectural rules enforced in review.

## License

OTKO is released under the **GNU Affero General Public
License v3.0** ([`LICENSE`](LICENSE)).

Plain-language summary (not legal advice — read the license itself):

- ✅ Use it for **research, education, and personal projects** with no
  obligation other than keeping the copyright notice intact.
- ✅ Modify and fork it freely.
- ⚠️ If you **distribute** it, modified or not, you must release your
  full source under AGPL-3.0.
- ⚠️ If you **run it as a network service** (e.g. host a modified
  version as a SaaS), you must release your modifications under
  AGPL-3.0.

In other words: anyone is free to learn from and build on this code,
but commercial forks and proprietary derivatives must contribute their
changes back to the community. If your use case needs a different
arrangement (e.g. a closed-source commercial license), please open an
issue to discuss.

Copyright © 2026 Ozan and contributors.