Core Concepts
A new software tool, the Grail+ Visualizer, automatically generates TikZ code to illustrate finite automata from the textual output of the Grail+ automata-theoretic command-line utilities.
Abstract
The article introduces Grail+, a C++ library of command-line utilities for manipulating various models of finite automata, regular expressions, and finite languages. While Grail+ provides a powerful text-based interface for automata-theoretic tasks, it lacks a way to visually represent the output.
To address this, the authors present the Grail+ Visualizer, a software tool that takes the textual representation of a finite automaton produced by Grail+ and generates TikZ code to illustrate the automaton. The visualizer parses the Grail+ output, extracts state labels and transition information, and then uses a layout algorithm to position the states and transitions in a visually appealing manner.
The article provides a detailed explanation of how the visualizer works, including the state layout procedure and the handling of special cases like self-loops and multiple transitions between states. An example is given to demonstrate the capabilities of the visualizer, showing how it can take a complex list of instructions and produce a clear, typeset illustration of the corresponding finite automaton.
The authors also discuss potential areas for improvement, such as optimizing the layout algorithm and allowing for user customization of the output. They suggest that implementing the visualizer as a LaTeX package could further streamline the workflow for users.
Overall, the Grail+ Visualizer aims to make the powerful Grail+ library more accessible and user-friendly, particularly for those who prefer a visual representation of finite automata.