Create a new scene with CharacterBody2D as root

rename to Player

Add a Sprite2D as child

Add a CollisionShape2D as child

Add Raycast2D as child

rename it to WallDetector

Select Sprite2D

Add Pacman_02.png as texture

Select the Sprite2D

Set scale to 3

Select CollisionShape2D

Add a New Circle Shape2D

Set the Radius to 20

Set up the correct collision structure

For the Player

Select the WallDetector

Set the Target Position to 0, 0

We will set it dynamically in code

Detect Collision Mask 2 (Walls)

Add a script to the Player node

Assign a class name

Add an export var for speed

Add references to the

Sprite2D

WallDetector

Add variables for

current direction

next direction

tile size (movement steps)

Input Buffering - Why we store current direction and next direction:

We use next_direction to capture the player's intention immediately, even if they press the button too early. We use current_direction to execute that action only when the physics engine confirms it is safe to do so (there is no wall blocking the path). This technique is called Input Buffering, and it is what makes arcade games feel "snappy" and "fair" instead of frustrating.

In original Pacman the player starts the game facing left!

In the ready function

Set current direction to left

Flip the sprite

Center the player in the grid cell

We will make calculate grid position next...

Create a helper function to find the center of a grid cell

Name the function calculate_grid_position

It returns a Vector2

Calculate x position

Calculate y position

Return x and y Vector

How the Math Works

The function calculate_grid_position does the heavy lifting:

position.x / 24: Converts pixel coordinates to map coordinates (e.g., 50px becomes 2.08 tiles).
floor(...): Removes the decimal to find the top-left corner of the tile (2.08 becomes 2).
* 24: Converts back to pixels (Tile 2 starts at 48px).
+ 12: Adds half a tile to find the exact center (48 + 12 = 60px).

Now, whenever you press a key to turn, Pac-Man will instantly snap to the perfect "lane" to make that turn!

Create another helper function to move the player into the center of the cell

Name the function snap_to_grid_center

Calculate the center of the current tile

If the turn is up or down

Keep the x position the same

If the turn is left or right

Keep the y position the same

Create a function to rotate the sprite

To face the current position

Call it update_rotation

If facing left set rotation to 180

if facing right set rotation to 90

if facing up set rotation to 270

if facing down set rotation to 90

We are rotating clockwise

To rotate anti-clockwise negate all the values

Create the get input function

to respond to player input

In physics process

If left was pressed

Next direction is left

And so on...

In physics process

get the input

If there is a turn

Point the RayCast in that direction

Update the RayCast immediately

If there is no wall

Move player to center of cell

Update the direction

Clear the direction queue

Set the velocity

Move and Slide

If the velocity has changed

Update the rotation

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