A Java-based puzzle game featuring a 3x3 grid of toggleable squares. The objective is to transform an all-white board into a target configuration by clicking squares that flip the colors of the clicked square and its adjacent neighbors.
Toggle Game is an interactive puzzle where players manipulate a 3x3 grid of black and white squares. Each square click toggles the color of the clicked square and its four orthogonal neighbors (north, south, east, west), creating a cascading color-flip effect.
The game board consists of 9 squares numbered as follows:
0 1 2
3 4 5
6 7 8
- White squares are represented by
1 - Black squares are represented by
0 - Every game starts with all white squares:
111111111
Clicking the middle square (button 4) transforms the board:
The middle square and its four neighbors flip from white to black.
Players are presented with a random target board configuration. The goal is to reach that configuration in the minimum number of moves.
- Interactive Game Board: Click any square to toggle it and its neighbors
- Minimum Moves Calculator: Automatically computes the optimal number of moves needed
- Path Solver: Generates the exact sequence of moves to reach the target
- Hint System: Reveals the next optimal move with visual highlighting
- BFS Algorithm: Uses breadth-first search to find optimal solution paths
- Binary Operations: Efficient state management using XOR operations
- State Tracking: Maintains parent-child relationships for path reconstruction
- Complete State Space: Handles all 512 (2^9) possible board configurations
- Language: Java
- Build Tool: Gradle
- Frontend: Java Swing
- Backend: Custom game engine with algorithm optimization
- Go to the Releases page
- Download the latest release archive (
.zipor.tar) - Extract the archive to your desired location
- Run the game:
On macOS/Linux:
cd Toggle-Game-<version>
./bin/ToggleGameOn Windows:
cd Toggle-Game-<version>
.\bin\ToggleGame.batRequirements: Java Runtime Environment (JRE) 11 or higher must be installed on your system.
Prerequisites:
- Java Development Kit (JDK) 11 or higher
- Gradle (included via wrapper)
Steps:
# Clone the repository
git clone https://github.com/pravinpaudel/Toggle-Game.git
cd Toggle-Game
# Build the project
./gradlew build
# Run the game
./gradlew run
# Or create a distribution
./gradlew installDist
# The executable will be in build/install/ToggleGame/bin/# Run all tests
./gradlew test
# View test results
open build/reports/tests/test/index.htmlsrc/
├── main/java/ToggleGame/
│ ├── Driver.java # Application entry point
│ ├── backend/
│ │ ├── GameHelper.java # Utility methods for state conversion
│ │ └── ToggleGameEngine.java # Core game logic and algorithms
│ └── frontend/
│ ├── GameGrid.java # UI grid component
│ ├── ToggleGameDisplay.java # Main display controller
│ └── ToggleGameInteraction.java # Interface definition
└── test/java/backend/
└── ToggleGameEngineTest.java # Comprehensive test suite
Each board state is represented as:
- String format: "111111111" (9 characters of '0' or '1')
- Binary format: Integer representation for efficient XOR operations
Each button has a predefined mask that determines which squares flip:
Button 0: 110100000 (flips positions 0, 1, 3)
Button 1: 111010000 (flips positions 0, 1, 2, 4)
...
The engine uses Breadth-First Search (BFS) to guarantee optimal solutions:
- Start from the current board state
- Explore all reachable states (up to 9 per move)
- Track parent-child relationships to reconstruct the path
- Return the shortest sequence when target is reached
Time Complexity: O(512 × 9) = O(1) since the state space is constant
Space Complexity: O(512) for visited states tracking
The project includes comprehensive test suites:
- FirstDeliverableTests: Basic initialization and identity tests
- BoardStatesTests: Button click handling and state updates
- MinimumRequiredMovesTests: Move counting accuracy
- PathToTargetTests: Solution path verification
All tests pass successfully ✅
This is an academic project. While contributions are not actively sought, feedback and suggestions are welcome.
This project is licensed under the terms specified in the LICENSE file.
Note: This implementation demonstrates efficient algorithms for solving combinatorial puzzles and serves as an educational example of search algorithms in action.