popeye

Popeye is a command line tool for analyzing chess problems and puzzles. It is primarily used for solving retrograde analysis problems, which involve working backwards from a given position to determine the possible moves and the game history. Popeye employs a powerful and customizable solving engine, capable of handling complex and diverse problems.

This command line tool supports a wide range of retrograde analysis scenarios, including capturing pawn promotions, castling rights, en passant captures, and various other chess-specific rules. It can handle problems with multiple solutions, dual solutions, and even help in finding the shortest possible solution.

Popeye uses a text-based interface, making it convenient for running and interacting with the solver from the command line. It provides several command line options and customizable settings for fine-tuning the solving process. The output generated by Popeye includes detailed solution paths, special conventions, and descriptive notations related to retrograde analysis.

Advanced users can extend and customize Popeye's functionality by writing their own scripts and input files in the software's own scripting language. Popeye also has a large library of chess-specific functions and commands built-in, making it a versatile tool for solving various retrograde analysis problems.

Overall, Popeye is a sophisticated command line tool for retrograde chess analysis, providing powerful solving capabilities and customization options for enthusiasts and professionals in the field.