Finite State Machines - Godot 4 Tutorial (Intermediate)

Step-by-Step Tutorial: Creating a Finite State Machine Program in Godot (Intermediate Level)

1. Introduction to Finite State Machine Program:

   • Finite State Machine (FSM) is a way to run code on an object or entity and have it run specific bits of code at a time, creating different states for the character.
   • FSM helps in separating logic, making it easier to handle, and allows for reusability of states on other objects.

2. Setting up the Finite State Machine Class:

   • Create a new script named State to serve as the base class for different states.
   • Define functions within the State class such as enter_state and exit_state.

3. Implementing the Finite State Machine Logic:

   • Define a class FiniteStateMachine to handle the states and switch between them.
   • Initialize the first state in the ready function and set it to state.

4. Creating the Enemy Goblin and States:

   • Create a new script for the Goblin character and define variables like max_speed and acceleration.
   • Implement the Wander State for the Goblin to move around randomly within the game environment.

5. Implementing the Chase State for the Goblin:

   • Create an Enemy Chase State to make the Goblin chase the mouse when it is visible.
   • Handle the logic to move the Goblin towards the mouse position and emit signals when the player is found or lost.

6. Handling State Transitions:

   • Connect the signals between the Wander State and Chase State using the FiniteStateMachine to switch states based on player visibility.

7. Testing and Refining the Goblin Behavior:

   • Test the Goblin behavior in the game environment to ensure it wanders, chases the mouse, and transitions between states smoothly.
   • Adjust parameters like acceleration and max speed to fine-tune the Goblin's movement.

8. Finalizing the Finite State Machine Program:

   • Ensure all dependencies like VisionCast and Animator are correctly set up for each state.
   • Connect all signals and complete the logic for smooth state transitions and behavior.

9. Conclusion and Additional Resources:

   • Test the complete Finite State Machine program to see the Goblin's behavior in action.
   • Explore further resources like the Godot 4 course for more in-depth learning on game development.

By following these steps, you can create a robust Finite State Machine program in Godot for your game characters to exhibit dynamic behaviors based on different states.