flagtrafo - The Flag Transformation Web Application

The flagtrafo project is a web application with an interactive user interface for playing with different transformations of flag complexes in the real projective plane. It provides transformations such as the bulge flow, the shear flow and the eruption flow.

flagtrafo can be viewed in your web browser. The geometric backend on the server side is the Python package projflag-lib/flagcomplex.

Setup instructions

Setup using pip (private use)

1. Download the flagtrafo source files and unpack them.
2. Open a command prompt of your choice and navigate to the flagtrafo folder. (Optionally activate a virtual environment.)
3. Execute pip install -r requirements.txt.
4. Start the application server with python3 src/app.py. Open the address shown in the command prompt in your browser, e.g. http://172.18.108.70:80/.

Hint for developers: You may want to activate the debug mode, which causes the server to update whenever you change the code. This can be achieved by uncommenting the line # app.config['DEBUG'] = True in the file src/app.py or by running $env:FLASK_ENV = "development" in your Windows PowerShell, or by running export FLASK_DEBUG in your Linux shell.

Setup using Docker (production use)

1. Install docker from www.docker.com. (On Windows: Start the Docker desktop client after the installation.)
2. Download the flagtrafo source files and unpack them.
3. Open a command prompt of your choice and navigate to the flagtrafo folder.
4. Execute docker build -t flagtrafo-image . in order to create a Docker image from the container.
5. Start the application server with docker run --name flagtrafo-container -d -p 80:80 flagtrafo-image. Open the address http://localhost/ in your browser in order to see the app.