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CONTRIBUTING.md

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+# Contributing to Pixal3D
+
+Thank you for your interest in contributing to **Pixal3D**! We welcome
+contributions from the community and are grateful for your support.
+
+## How to Contribute
+
+### Reporting Issues
+
+If you encounter bugs, unexpected behavior, or have feature requests, please
+open an issue on GitHub. Before creating a new issue:
+
+1. **Search existing issues** to avoid duplicates.
+2. **Use issue templates** if available (Bug Report / Feature Request).
+3. Provide as much detail as possible, including:
+   - Steps to reproduce
+   - Expected vs. actual behavior
+   - Environment details (OS, Python version, GPU, etc.)
+   - Relevant logs or screenshots
+
+### Pull Requests
+
+We actively welcome pull requests. To ensure a smooth review process:
+
+1. **Fork the repository** and create your branch from `master`:
+   ```bash
+   git checkout -b feature/my-feature
+   # or
+   git checkout -b fix/my-bugfix
+   ```
+2. **Install development dependencies** and ensure your changes pass existing tests.
+3. **Write clear, concise commit messages** following conventional commit format:
+   - `feat:` for new features
+   - `fix:` for bug fixes
+   - `docs:` for documentation changes
+   - `refactor:` for code restructuring
+   - `test:` for adding or updating tests
+4. **Update documentation** if your changes impact usage, setup, or public APIs.
+5. **Open a Pull Request** with a clear title and description linking related issues.
+
+### Code Style
+
+- Follow PEP 8 for Python code.
+- Use meaningful variable and function names.
+- Add docstrings to public functions and classes.
+- Keep functions focused and modular.
+
+### Pre-commit Checks
+
+Before submitting a PR, please verify:
+
+```bash
+# Run linting
+flake8 src/
+
+# Run type checking
+mypy src/
+
+# Run tests
+pytest tests/
+```
+
+### Documentation
+
+If your contribution changes user-facing behavior, please update:
+
+- `README.md` / `README.zh-CN.md` (if applicable)
+- Inline code documentation
+- Example notebooks or scripts in `examples/`
+
+## Development Setup
+
+```bash
+# Clone your fork
+git clone https://github.com/YOUR_USERNAME/Pixal3D.git
+cd Pixal3D
+
+# Install dependencies
+pip install -r requirements.txt
+pip install -r requirements-dev.txt  # if available
+
+# Verify installation
+python -c "import pixal3d; print(pixal3d.__version__)"
+```
+
+## License
+
+By contributing to Pixal3D, you agree that your contributions will be licensed
+under the [MIT License](LICENSE).
+
+## Questions?
+
+Feel free to open a discussion or reach out via the project page at
+https://ldyang694.github.io/projects/pixal3d/.
+
+---
+
+We appreciate every contribution, whether it's code, documentation, bug reports,
+or feature suggestions. Thank you for helping make Pixal3D better! 🎉