Prologot

Prologot is a Godot 4 extension that embeds SWI-Prolog, bringing logic programming to your games on Linux, macOS, and Windows. Use Prolog for AI decision-making, dialogue systems, rule engines, pathfinding, and more. This extension offers:

• SWI-Prolog integration via GDExtension
• Interactive Prolog console in the Godot editor
• Query execution with variable bindings
• Dynamic fact assertion and retraction
• Load Prolog from files or code strings
• Knowledge-base management
• Type conversion between Prolog terms and Godot Variants

Prolog is a logic programming language. You describe facts and rules, then ask questions (queries). The engine searches for values that make a question true — it does not run a fixed sequence of instructions like GDScript.

Think of it as a database plus inference:

• Facts are records you assert: parent(tom, bob).
• Rules derive new truths: “X is a grandparent of Z if X is parent of Y and Y is parent of Z.”
• Queries ask whether something holds, or which values make it hold: parent(tom, Who)? → Who = bob, then Who = liz.

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Documentation

• Getting started: Follow the Installation Guide to set everything up. Quick build on Ubuntu:

sudo apt-get install g++ make pkg-config swi-prolog swi-prolog-nox
pip install scons

git clone https://github.com/Lecrapouille/Prologot.git
cd Prologot
make GODOT_CPP=4.5 all

• Try the demo: Once built, run the Interactive Demo to see Prologot execute Prolog examples and display the results:

make run-demo

• Mini Dungeon: A short dungeon crawler whose monster AI is powered by Prolog:

make run-mini-dungeon

• Galactic Customs: A logic puzzle where you play customs officer and approve or deny galactic travelers:

make run-galactic_customs

• Learn Prolog and Prologot: The Glossary introduces Prolog basics; Getting Started walks you through Prologot. Prolog veterans: see Notes for Prolog Developers for switching from SWI-Prolog to Prologot—API mapping and common pitfalls.

• Build your game: The API Reference covers the full syntax. Use Cases suggests patterns for game logic. For a minimal script-only sample, see hello_world_prologot.gd.

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Project Structure

Prologot/
├── src/                              # C++ GDExtension source
│   ├── Prologot.hpp / Prologot.cpp   # Core engine: init, consult, assert, solve
│   ├── PrologQuery.hpp / .cpp        # Lazy query handle (PrologQuery)
│   ├── PrologGoal.hpp / .cpp         # Goal builder (PrologGoal)
│   ├── PrologTerm.hpp / .cpp         # Term wrapper (PrologTerm)
│   ├── PrologSolution.hpp / .cpp     # Solution bindings (PrologSolution)
│   ├── PrologPredicate.hpp / .cpp    # Predicate builder (PrologPredicate)
│   ├── PrologVariable.hpp / .cpp     # Logic variable (PrologVariable)
│   ├── PrologObject.hpp / .cpp       # Opaque Prolog term handle (PrologObject)
│   ├── PrologConversion.hpp / .cpp   # Prolog ↔ Godot Variant conversion
│   ├── PrologExposure.cpp            # expose_property / expose_method bridge
│   ├── register_types.h              # GDExtension registration header
│   └── register_types.cpp            # Registers native classes with Godot
├── tests/                            # Headless regression suite
│   ├── run_tests.gd                  # Test runner (SceneTree entry point)
│   ├── test_prologot.gd              # Unit tests
├── addons/prologot/                  # Godot editor plugin
│   ├── plugin.cfg                    # Plugin manifest
│   ├── plugin.gd                     # EditorPlugin entry point
│   ├── prologot_boot.gd              # Shared initialize() and bundled SWI home
│   ├── prologot_facade.gd            # GDScript wrapper around the native API
│   ├── prologot_singleton.gd         # Autoload (PrologotEngine) and named KBs
│   ├── prologot_node.gd              # Scene-tree node wrapper (PrologotNode)
│   ├── prolog_knowledge.gd           # Inspectable knowledge-base resource
│   └── prologot_dock.gd              # In-editor Prolog console UI
├── demos/                            # Sample Godot projects
│   ├── showcases/                    # Interactive API walkthrough
│   │   ├── examples/*.pl             # 01–06: queries, rules, pathfinding, AI, …
│   │   ├── prologot-demos.gd         # Demo UI and logic
│   │   └── prologot-demos.tscn       # Demo scene
│   ├── mini_dungeon/                 # Dungeon crawler with Prolog-driven AI
│   │   ├── prolog/*.pl               # dungeon, combat, ai, rules
│   │   ├── scripts/*.gd              # player, goblin, dungeon, door, …
│   │   └── ui/procedural_actor.gd    # Procedural pixel-art rendering
│   └── galactic_customs/             # Customs-booth logic puzzle
│       ├── rules/galactic_customs.pl # Base knowledge base
│       ├── scripts/main.gd           # Game loop and Prolog integration
│       ├── scripts/alien_sprite.gd   # Alien portrait display
│       └── ui/galactic_atlas.gd      # Sprite atlas + button skinning
├── doc/                              # Guides, API reference, and examples
│   └── hello_world_prologot.gd       # Minimal script-only sample
├── bin/                              # Build output (created by make / scons)
│   ├── linux/                        # .so + bundled swipl/ runtime
│   ├── windows/                      # .dll + bundled swipl/ runtime
│   ├── macos/                        # .dylib + bundled swipl/ runtime
│   └── prologot.gdextension          # Generated GDExtension manifest
├── godot-cpp-*/                      # godot-cpp bindings (cloned by SConstruct)
├── SConstruct                        # Build: compile, copy SWI runtime, generate .gdextension
└── Makefile                          # Shortcuts (build, test, run demos)

License

This project is licensed under the MIT License—see the LICENSE file for details.

Parts of this project were developed with AI assistance.