pacman - career center east video game (harman)videogame-harman.weebly.com › ... ›...

Note: I have started this exercise for you so you do not have to make all of the box colliders.

maze was created, open the file named “unity_pacman_create_maze.

Adding Pac-Man

The Pac-Man Sprite

Now it's time for the most important part of our game: Pac

direction:

- right

- left

- up

- down

All the animations are in one image, where

We will use the following Import Settings for it:

Slicing the Pac-Man Sprite

It's important to set the Sprite Mode to Multiple

Let's open the Sprite Editor by clicking the button:

Pacman

Note: I have started this exercise for you so you do not have to make all of the box colliders. If you

“unity_pacman_create_maze.”

Now it's time for the most important part of our game: Pac-Man. We will need one animation for each movement

there is one animation per row. The image is called

for it:

Multiple, which tells Unity that there is more than one Pac

by clicking the button:

If you want to see how the

Man. We will need one animation for each movement

there is one animation per row. The image is called pacman.png.

, which tells Unity that there is more than one Pac-Man in our Sprite.

Now we can tell Unity where each Pac-Man animation slice is located in our Sprite. We will select

as 16 x 16 Grid and press the Slice button afterwards:

Once the Sprite was sliced, we can close the Sprite Editor again. If Unity asks us about

we will click on Apply.

As a result we now have 12 slices under our Pac

Creating the Pac-Man Animations

Okay so now that we have the animation slices, we can create our 4 animations from it. As a reminder, here are the

animations that we will need:

• right (Slice 0, 1 and 2)

• left (Slice 3, 4 and 5)

• up (Slice 6, 7 and 8)

• down (Slice 9, 10 and 11)

Man animation slice is located in our Sprite. We will select

button afterwards:

Once the Sprite was sliced, we can close the Sprite Editor again. If Unity asks us about Unapplied Import Settings

As a result we now have 12 slices under our Pac-Man Sprite in theProject Area:


Man animation slice is located in our Sprite. We will select Slice and then slice it

Unapplied Import Settings then


Let's create the right animation. We will begin by selecting the first three slices in the

And then dragging them into the Scene:

Now whenever we drag several slices into the Scene, Unity

hence why it automatically asks us where to save the animation. Let's save it as

new PacmanAnimation folder.

Unity just added a pacman_0 GameObject to the

animation. We will begin by selecting the first three slices in the Project Area

Now whenever we drag several slices into the Scene, Unity will know that we want to create an animation from them,

hence why it automatically asks us where to save the animation. Let's save it as right.anim in a

GameObject to the Scene and two files to the Project Area:

Project Area:

will know that we want to create an animation from them,

in a

The first file is the animation state machine that specifies things like the animation speed and blend trees. The second

one is the animation itself.

We will repeat this process for the rest of the animations

down).

Here is what our Hierarchy looks like afterwards:

Cleaning up after Unity

Unity created one GameObject for each animation, but we only need the first one as we will see soon. Let's select the

other 3 and then right click and delete them:

A similar thing happened in our Project Area


We will repeat this process for the rest of the animations (Slice 3, 4, 5 for left; Slice 6, 7, 8 for up and Slice 9, 10, 11 for

looks like afterwards:


them:

Project Area. We now have 4 animations and 4 animation state machines:


6, 7, 8 for up and Slice 9, 10, 11 for


animation state machines:

Again we only need one animation state machine, so let's delete the other three:

The Pac-Man Animation State Machine

Right now we have 4 animation files, but Unity doesn't know when to play which animation yet. The solution to our

problem is part of Unity's unbelievably powerful

that has 4 states:

• right

• left

• up

• down

We will also add Transitions so Unity knows when to switch from one animation state to another.

Note: Unity will play the right animation over and over again while in

switch to another state. Unity does all of that automatically, all we have to do is notify it about Pac

direction from within a Script later on.

Okay so let's double click the pacman_0 animation state machine file in our

Again we only need one animation state machine, so let's delete the other three:


problem is part of Unity's unbelievably powerful Mecanim animation system. We will need a animation state machine

so Unity knows when to switch from one animation state to another.

animation over and over again while in right state. It will use Transitions

state. Unity does all of that automatically, all we have to do is notify it about Pac

animation state machine file in our Project Area:


animation system. We will need a animation state machine

so Unity knows when to switch from one animation state to another.

Transitions to know when to

state. Unity does all of that automatically, all we have to do is notify it about Pac-Man's movement

Now we can see the state machine in the Animator

Creating the Other States

The right state is already in the Animator, so let's add the

the ShipAnimation folder from our Project Area

This process can be repeated for the remaining two states:

The big deal about Mecanim is that it will take care of the animation states on its own, fully automatically. All we have to

do is tell Mecanim to watch out for our Pac

between animation states on its own, without us having to do anything.

Animator:

state is already in the Animator, so let's add the left state by simply dragging the left.anim

Project Area into the Animator:

can be repeated for the remaining two states:


do is tell Mecanim to watch out for our Pac-Man's movement direction, nothing more. Mecanim will then switch

between animation states on its own, without us having to do anything.

left.anim file from


e. Mecanim will then switch

Creating the Parameters

So let's tell Mecanim that it should watch out for Pac Man's movement direction. A movement direction is of type

Vector2, the following image shows some possible movement directions:

Our Pac-Man will only have 4 movement directions

4 Transitions in our animation state machine:

• If DirY > 0 then go to up (like DirY=1, DirY=2, DirY=3 and so on)

• If DirY < 0 then go to down (like DirY=-

• If DirX > 0 then go to right (like DirX=1, DirX=2, DirX=3 and so on)

• If DirX < 0 then go to left (like DirX=-1, DirX=

Let's take a look at the left area of the Animator and select the

Here we will click on the + at the right and then add one Parameter of type

Parameter of type Float with the name DirY

Later on we can set those parameters from within a Script by writing:

GetComponent<Animator>().SetFloat("DirX"

GetComponent<Animator>().SetFloat("DirY"

Creating the Transitions

We want Unity to automatically switch to different animation states based on

achieve just that. For example, we could add a Transition from

considered best practice to have a small error tolerance because floating point comparison

why we will use DirX > 0.1 instead.

Now we would also have to use a DirX > 0.1

work, we can use Unity'sAny State.

The Any State stands for literally any state. So if we create a Transition from

creating a Transition fromleft, up and down


ng image shows some possible movement directions:

Man will only have 4 movement directions (up, down, left, right). Which means that we only need the following

in our animation state machine:

=1, DirY=2, DirY=3 and so on)

-1, DirY=-2, DirY=-3 and so on)

(like DirX=1, DirX=2, DirX=3 and so on)

1, DirX=-2, DirX=-3 and so on)

Let's take a look at the left area of the Animator and select theParameters tab:

at the right and then add one Parameter of type Float with the name

DirY:

can set those parameters from within a Script by writing:

"DirX", 0);

"DirY", 0);

We want Unity to automatically switch to different animation states based on those parameters. Transitions are used to

achieve just that. For example, we could add a Transition from left to right with the Condition that

considered best practice to have a small error tolerance because floating point comparison is not always perfect, hence

DirX > 0.1 Transition from every other state to right. To save us from doing all this

any state. So if we create a Transition from Any State to right

down to right.


. Which means that we only need the following

with the name DirX and another

those parameters. Transitions are used to

with the Condition that DirX > 0. However it's

is not always perfect, hence

. To save us from doing all this

right then it's the same as

Let's right click the Any State and select Make Transition

Now we can click on the white arrow and take a look at the

in other words, when it should switch). We will set it to

Note: press the + at the bottom right to add a Condition.

Make Transition. Afterwards we can drag the white arrow onto the

Now we can click on the white arrow and take a look at the Inspectorwhere we can modify the Transition's

. We will set it to DirX > 0.1:

at the bottom right to add a Condition.

. Afterwards we can drag the white arrow onto the right state:

where we can modify the Transition's Condition (or

Let's also disable Can Transition To Self in the

Note: this avoids weird situations where an animation would be restarted all the time while holding down a movement

key.

As result, whenever Pac-Man walks to the right

animation.

We will add 3 more Transitions:

• Any State to left with the Condition DirX <

• Any State to up with the Condition DirY > 0.1

• Any State to down with the Condition

Here is how it looks in the Animator now:

in the Settings:


Man walks to the right (DirX > 0.1), the animator will switch to the right

DirX < -0.1

DirY > 0.1

DirY < -0.1


right state and play the

We are almost done with our animation state machine. There is one last adjustment to be made here, so let's select all

states and then modify their Speed in the Inspector

If we press Play then we can already see the

Pac-Man Naming and Positioning

We want to keep everything nice and clean, so let's select the

it to pacman (right click it and select rename, or

We will also change its position to (14, 14) so it's not outside the maze anymore:

Pac-Man Physics

Right now Pac-Man is only an image, nothing more. He is not part of the physics world, things won't collide with him and

he can't move or anything else. We will need to add a

things will collide with Pac-Man instead of walking right through him.

Pac-Man is also supposed to move around. A Rigidbody takes care of stuff like grav

make things move. As a rule of thumb, everything in the physics world that is supposed to move around needs

a Rigidbody.


Inspector so that the animation doesn't look too fast:

then we can already see the right animation:

We want to keep everything nice and clean, so let's select the pacman_0GameObject in the Hierarchy

(right click it and select rename, or press F2) :

so it's not outside the maze anymore:

Man is only an image, nothing more. He is not part of the physics world, things won't collide with him and

anything else. We will need to add a Collider to make him part of the physics world, which means that

Man instead of walking right through him.

Man is also supposed to move around. A Rigidbody takes care of stuff like gravity, velocity and other forces that



so that the animation doesn't look too fast:

Hierarchy and then rename

Man is only an image, nothing more. He is not part of the physics world, things won't collide with him and

to make him part of the physics world, which means that

ity, velocity and other forces that


Let's select the pacman GameObject in the

as Add Component->Physics 2D->Rigidbody 2D

following image:

Alright, Pac-Man is now part of the physics world. He will collide with other things and other things w

This will also cause the OnCollisionEnter2D

The Movement Script

Alright now there are several ways to make Pac

checks for Arrow-Key presses and then move Pac

wouldn't feel very good.

Instead we will try to be more exact. Whenever the player presses one of the Arrow

1 unit into the desired direction. The Pac-Dots

it only makes sense that Pac-Man always moves exactly one unit.

Let's select pacman in the Hierarchy and press

select CSharp as language. We will also move the Script into a new

clean):

Alright let's double click the Script so it opens:

using UnityEngine;

using System.Collections;

public class PacmanMove : MonoBehaviour

// Use this for initialization

void Start () {

}

// Update is called once per frame

void Update () {

}

}

Hierarchy, select Add Component->Physics 2D->Circle

Rigidbody 2D. It's important that we use exactly the same settings as shown in the

Man is now part of the physics world. He will collide with other things and other things w

OnCollisionEnter2D function to be called in any Script that is attached to Pac

Alright now there are several ways to make Pac-Man move. The easiest way would be to create a Script

Key presses and then move Pac-Man a bit up/down/left/right when needed. This would work, but it

Instead we will try to be more exact. Whenever the player presses one of the Arrow-Keys, Pac-

Dots (the food) will also be positioned with a 1 unit distance between them, so

Man always moves exactly one unit.

and press Add Component->New Script, name it PacmanMove

as language. We will also move the Script into a new Scripts folder in the Project Area

Alright let's double click the Script so it opens:

MonoBehaviour {

Circle Collider 2D as well

. It's important that we use exactly the same settings as shown in the

Man is now part of the physics world. He will collide with other things and other things will collide with him.

function to be called in any Script that is attached to Pac-Man.

Man move. The easiest way would be to create a Script that simply

Man a bit up/down/left/right when needed. This would work, but it

-Man should move exactly

will also be positioned with a 1 unit distance between them, so

PacmanMove and

Project Area (just to keep things

The Start function is automatically called by Unity when starting the game. The Update function is automatically called

over and over again, roughly 60 times per second (this depends on the current frame rate, it can be lower if there are a

lot of things on the screen).

There is yet another type of Update function, which is FixedUpdate. It's also called over and over again, but in a fixed

time interval. Unity's Physics are calculated in the exact same time interval, so it's always a good idea to

use FixedUpdate when doing Physics stuff:

using UnityEngine;


public class PacmanMove : MonoBehaviour {

void Start() {

}

void FixedUpdate() {

}

}

We will need a public variable so that we can modify the movement speed in the Inspector later on:

using UnityEngine;



public float speed = 0.4f;

void Start() {

}


}

}

We will also need a way to find out if Pac-Man can move into a certain direction or if there is a wall. So for example if we

would want to find out if there is a wall at the top of Pac-Man, we could simply cast a Line from one unit above of Pac-

Man to Pac-Man and see if it hit anything. If it hit Pac-Man himself then there was nothing in-between, otherwise there

must have been a wall.

Here is the function:

bool valid(Vector2 dir) {

// Cast Line from 'next to Pac-Man' to 'Pac-Man'

Vector2 pos = transform.position;

RaycastHit2D hit = Physics2D.Linecast(pos + dir, pos);

return (hit.collider == collider2D);

}

Note: we simply casted the Line from the point next to Pac-Man (pos + dir) to Pac-Man himself (pos).

We will also need a function that makes Pac-Man move 1 unit into the desired direction. Of course we could just do:

transform.position += dir;

But this would look too abrupt because it's such a huge step. Instead we want him to go there smoothly, one small step

at the time. Let's store the movement destination in a variable and then use FixedUpdate to go towards that destination

step by step:

using UnityEngine;




Vector2 dest = Vector2.zero;

void Start() {

dest = transform.position;

}


// Move closer to Destination

Vector2 p = Vector2.MoveTowards(transform.position, dest, speed);

GetComponent<Rigidbody2D>().MovePosition(p);

}

bool valid(Vector2 dir) {

// Cast Line from 'next to Pac-Man' to 'Pac-Man'

Vector2 pos = transform.position;

RaycastHit2D hit = Physics2D.Linecast(pos + dir, pos);

return (hit.collider == collider2D);

}

}

Note: we used GetComponent to access Pac-Man's Rigidbody component. We then use it to do the movement (we

should never use transform.position to move GameObjects that have Rigidbodies).

Let's also watch out for arrow key presses whenever we are not moving.

Note: we are not moving if the current position equals the destination.

Here is our FixedUpdate function with Input checks:



Vector2 p = Vector2.MoveTowards(transform

GetComponent<Rigidbody2D>().MovePosition

// Check for Input if not moving

if ((Vector2)transform.position == dest) {

if (Input.GetKey(KeyCode.UpArrow) &&

dest = (Vector2)transform.position +

if (Input.GetKey(KeyCode.RightArrow)


if (Input.GetKey(KeyCode.DownArrow)

dest = (Vector2)transform.position -

if (Input.GetKey(KeyCode.LeftArrow) &&


}

}

Note: transform.position is casted to Vector2

Vector2.up means left and -Vector2.right means

If we save the Script and press Play then we can now move Pac

Here is our FixedUpdate function with Input checks:

transform.position, dest, speed);

MovePosition(p);

&& valid(Vector2.up))

+ Vector2.up;

&& valid(Vector2.right))

+ Vector2.right;

) && valid(-Vector2.up))

Vector2.up;

&& valid(-Vector2.right))

Vector2.right;

Vector2 because this is the only way to compare or add another Vector2. Also

means down.

then we can now move Pac-Man with the arrow keys:

because this is the only way to compare or add another Vector2. Also -

Setting the Animation Parameters

Right now we can perfectly move Pac-Man around the maze, but the animator

problem, let's just modify our code to calculate the current movement direction and then set the animator parameters:



Vector2 p = Vector2.MoveTowards(transfo


// Check for Input if not moving

if ((Vector2)transform.position == dest) {

if (Input.GetKey(KeyCode.UpArrow) &&


if (Input.GetKey(KeyCode.RightArrow)


if (Input.GetKey(KeyCode.DownArrow)


if (Input.GetKey(KeyCode.LeftArrow) &&


}

// Animation Parameters

Vector2 dir = dest - (Vector2)transform.position



}

Note: we calculated the current movement

current position from the destination.

And that's all there is to it. If we save the Script and press

Drawing Pac-Man in the Foreground

Before we start to work on the Pac-Dots, we should make sure that Pac

making a 2D game, so there isn't really any

pleases. Let's make sure that Unity always draws Pac

There are two ways to do this. We could either change the

the Order in Layer property. The Sorting Layer

simply change the Order in Layer to 1:

Man around the maze, but the animator doesn't play all the animations yet. No


transform.position, dest, speed);

MovePosition(p);

&& valid(Vector2.up))

+ Vector2.up;

&& valid(Vector2.right))

+ Vector2.right;

) && valid(-Vector2.up))

Vector2.up;

&& valid(-Vector2.right))

Vector2.right;

position;

"DirX", dir.x);

"DirY", dir.y);

direction with basic vector math. All we had to do was subtract the

the Script and press Play then we can now see the proper animations:

Dots, we should make sure that Pac-Man is always drawn in

Z order like in 3D games. This means that Unity just draws objects as it

pleases. Let's make sure that Unity always draws Pac-Man in front of everything else.

We could either change the Sprite Renderer's Sorting Layer property or we could change

Sorting Layer is important for bigger games with far more objects. For us it's enough to

doesn't play all the animations yet. No


ection with basic vector math. All we had to do was subtract the

then we can now see the proper animations:

Man is always drawn in front of them. We are

order like in 3D games. This means that Unity just draws objects as it

property or we could change

is important for bigger games with far more objects. For us it's enough to

Note: Unity draws objects sorted by their order. It starts with the lowest order and continues with higher orders. So if

Pac-Man has the order 1 then he's always drawn after the maze and the food and anything else with order 0. And

because he's drawn after everything else, he's automatically in front of everything else.

The Pac-Dots

The little dots that Pac-Man can eat are called Pac

drawing a small 2x2px image of a Pac-Dot: It is in your sprites folder named

Afterwards we can drag it into the Scene. We want to be notified when Pac

is select Add Component->Physics 2D->Box Collider 2D

Unity draws objects sorted by their order. It starts with the lowest order and continues with higher orders. So if

Man has the order 1 then he's always drawn after the maze and the food and anything else with order 0. And

ything else, he's automatically in front of everything else.

Man can eat are called Pac-Dots. Some might now them as 'fruits' or just 'food'. We will begin by

It is in your sprites folder named “pacdot.png.”

. We want to be notified when Pac-Man walks over a Pac

Box Collider 2D in the Inspector and then select Is Trigger

Unity draws objects sorted by their order. It starts with the lowest order and continues with higher orders. So if

Man has the order 1 then he's always drawn after the maze and the food and anything else with order 0. And

Dots. Some might now them as 'fruits' or just 'food'. We will begin by

Man walks over a Pac-Dot. All we have to do

Is Trigger:

Note: a Collider with IsTrigger enabled only receives collision information, it does not physically collide with other things.

Unity will automatically call the OnTriggerEnter2D function whenever Pac-Man or one of the Ghosts walk over the Pac-

Dot.

So let's select Add Component->New Script, name it Pacdot, selectCSharp, move it into our Scripts folder and then open

it:

using UnityEngine;


public class Pacdot : MonoBehaviour {


void Start () {

}


void Update () {

}

}

We won't need the Start or the Update function, so let's remove both of them. Instead we will use the previously

mentioned OnTriggerEnter2Dfunction:

using UnityEngine;



void OnTriggerEnter2D(Collider2D co) {

// Do Stuff...

}

}

Now this one is easy. We will check if the thing that walked over the Pac

the Pac-Dot:

using UnityEngine;




if (co.name == "pacman")

Destroy(gameObject);

}

}

Note: if we wanted to implement a highscore in our game, then this would be the place to increase it.

Now we can right click the Pac-Dot in the Hierarchy

that we always position the Pac-Dots at rounded coordinates like

Here is the result after duplicating and positioning the Pac

If we press Play then Pac-Man can now eat them:

thing that walked over the Pac-Dot was Pac-Man, and if so then we will destroy


Hierarchy, select Duplicate and move it to the next free position. It's i

Dots at rounded coordinates like (1, 2) and never (1.003, 2.05)

Here is the result after duplicating and positioning the Pac-Dot over and over again:

Man can now eat them:

Man, and if so then we will destroy


and move it to the next free position. It's important

(1.003, 2.05).

Feel free to also move all those Pac-Dots into

So that we can collapse the maze GameObject in order to have a clean view at the Hierarchy:

The Ghosts

A good Pac-Man clone needs some enemies, so let's add a few ghosts.

The Red Ghost Image

As usual we will begin by drawing a ghost Sprite with all the animations in it. Each row will contain one animation:

• right

• left

• up

• down

The first one will be the red ghost, also known as

.

Let's select it in the Project Area and then modify the

into the maze GameObject:

So that we can collapse the maze GameObject in order to have a clean view at the Hierarchy:

Man clone needs some enemies, so let's add a few ghosts.

usual we will begin by drawing a ghost Sprite with all the animations in it. Each row will contain one animation:

The first one will be the red ghost, also known as Blinky: It is in the sprites folder.

and then modify the Import Settings in the Inspector:

usual we will begin by drawing a ghost Sprite with all the animations in it. Each row will contain one animation:

Creating the Animations

It's important that we set the Sprite Mode to

the Sprite Editor button and slice it as a 16 x 16

Afterwards we can close the Sprite Editor and press

into the Scene, just like we did with Pac-Man.

At first we will drag Slice 0 and 1 into the Scene and save the animation as

We will repeat this process for:

• Slice 2 and 3 as left

• Slice 4 and 5 as up

• Slice 6 and 7 as down

to Multiple again because our Sprite contains several slices. Let's click

16 x 16 grid:

and press Apply. Now it's time to create the animations by dragging the slices

Man.

into the Scene and save the animation as right.anim in a new

several slices. Let's click

. Now it's time to create the animations by dragging the slices

BlinkyAnimation folder.

Cleaning up after Unity

Now we can clean up the Hierarchy again by deleting the

We can also delete the blinky_2, blinky_4 and

again by deleting the blinky_2,blinky_4 and blinky_6 GameObjects:

and blinky_6 files from theBlinkyAnimation folder in the

GameObjects:

folder in the Project Area:

The Animation State Machine

Let's double click the blinky_0 file to open the Animator:

We will create the exact same animation state machine that we used for Pac

the animations, create the Parameters and then set the Transitions:

• Any State to right with the Condition DirX > 0.1

• Any State to left with the Condition DirX <

• Any State to up with the Condition DirY > 0.1

• Any State to down with the Condition

Here is the final animation state machine in the Animator:

Renaming and Positioning Blinky

Let's make sure to keep everything nice and clean. We will select the

it to blinky:

file to open the Animator:

We will create the exact same animation state machine that we used for Pac-Man before. All we have to do is drag in

the animations, create the Parameters and then set the Transitions:

DirX > 0.1

DirX < -0.1

DirY > 0.1

DirY < -0.1

Here is the final animation state machine in the Animator:

Let's make sure to keep everything nice and clean. We will select theblinky_0 GameObject in the

Man before. All we have to do is drag in

GameObject in the Hierarchy and rename

We will also change the position in the Inspector

Ghost Physics

Alright so Blinky should be part of the Physics world again. Let's select

2D in the Inspector and assign the following properties:

Note: we enabled Is Trigger because Blinky

Blinky is also supposed to move around the maze, which means that we will need to add a

select Add Component->Physics 2D->Rigidbody 2D

Bringing Blinky to the Foreground

Just like Pac-Man, we want Blinky to be drawn in the foreground, in front of the Pac

the Order in Layervalue to 1:

Inspector so that Blinky is in the middle of the maze:

linky should be part of the Physics world again. Let's select Add Component->Physics 2D

and assign the following properties:

is a ghost, and ghosts can walk right through things.

Blinky is also supposed to move around the maze, which means that we will need to add a Rigidbody

Rigidbody 2D:

Man, we want Blinky to be drawn in the foreground, in front of the Pac-Dots. All we have to do to is set

Physics 2D->Circle Collider

is a ghost, and ghosts can walk right through things.

Rigidbody to him. Let's

Dots. All we have to do to is set

The Ghost Movement

Alright so we don't know very much about how the AI works in the original Pac-Man game, except for the fact that it's

deterministic (which is a fancy word for not-random). It also appears as some ghosts are more focused on moving

around the maze, while others are more focused on following Pac-Man, or perhaps even trying to position themselves in

front of him.

In this Tutorial we will focus on the easiest of the AI options: moving around the maze. We will create a waypoint

movement Script that makes Blinky run along a certain path. What sounds almost too simple is actually a pretty decent

solution to our AI problem. The longer and the more complex the path, the harder it is for the player to evade Blinky.

Let's select Add Component->New Script, name it GhostMove, selectCSharp and then move it into our Scripts folder.

Afterwards we can double click it so it opens:

using UnityEngine;


public class GhostMove : MonoBehaviour {


void Start () {

}


void Update () {

}

}

We won't need the Start or the Update function, instead we will use theFixedUpdate function (because it's meant for

physics stuff like movement):

using UnityEngine;



void FixedUpdate () {

}

}

Let's add a public Transform array so that we can set the waypoints in the Inspector later on:

using UnityEngine;



public Transform[] waypoints;


}

}

Note: an array means that it's more than just one Transform.

We will also need some kind of index variable that keeps track of the waypoint that Blinky is currently walking towards:

using UnityEngine;




int cur = 0;


}

}

Note: the current waypoint can always be accessed with waypoints[cur].

And of course a movement speed variable:

using UnityEngine;




int cur = 0;



}

}

Now we can use the FixedUpdate function to go closer to the current waypoint, or select the next one as soon as we

reached it:


// Waypoint not reached yet? then move closer

if (transform.position != waypoints[cur].position) {

Vector2 p = Vector2.MoveTowards(transform.position,

waypoints[cur].position,

speed);

GetComponent<Rigidbody2D>().MovePosition(p);

}

// Waypoint reached, select next one

else cur = (cur + 1) % waypoints.Length;

}

Note: we used the Vector2.MoveTowards function to calculate a point that is a bit closer to the waypoint. Afterwards we

set the ghost's position withrigidbody2D.MovePosition. If the waypoint is reached then we increase thecur variable by

one. We also want to reset the cur to 0 if it exceeds the list length. We could use something like if (cur ==

waypoints.Length) cur = 0, but using the modulo (%) operator makes this look a bit more elegant.

Let's not forget to set the Animation Parameters too:


// Waypoint not reached yet? then move closer

if (transform.position != waypoints[cur].position) {

Vector2 p = Vector2.MoveTowards(transform

waypoints[cur].position

speed);


}

// Waypoint reached, select next one

else cur = (cur + 1) % waypoints.Length;

// Animation

Vector2 dir = waypoints[cur].position - transform



}

Great, there is one last thing to add to our Script. The ghosts should destroy Pac


if (co.name == "pacman")

Destroy(co.gameObject);

}

Note: feel free to decrease Pac-Man's lives or show a

Adding Waypoints

Alright, let's add some waypoints for Blinky

We will rename it to Blinky_Waypoint0 and then assign a

Note: a Gizmo is just a visual helper, we don't see it when playing the game

Let's also position it at (15, 20). Here is how it looks in the Scene now:

transform.position,

position,

MovePosition(p);

transform.position;

"DirX", dir.x);

"DirY", dir.y);

Great, there is one last thing to add to our Script. The ghosts should destroy Pac-Man upon colliding with him:

or show a Game Over screen at this point.

Alright, let's add some waypoints for Blinky. We will begin by selectingGameObject->Create Empty

and then assign a Gizmo to it so we can see it easier in the Scene:

Note: a Gizmo is just a visual helper, we don't see it when playing the game.

. Here is how it looks in the Scene now:

Man upon colliding with him:

Create Empty from the top menu.

to it so we can see it easier in the Scene:

Now we can duplicate the Waypoint, rename it to

Then Blinky_Waypoint2 at (10, 14):

And Blinky_Waypoint3 at (19, 14):

And finally Blinky_Waypoint3 at (19, 20):

And because our Movement Script will automatically continue to walk to the first waypoint after the last one was

reached, we will have a perfect loop.

Now we can duplicate the Waypoint, rename it to Blinky_Waypoint1and position it at (10, 20)


(10, 20):


Let's select blinky in the Hierarchy again and then drag one wayp

our GhostMove Script:

If we press Play then we can see how Blinky moves along the waypoints:

Of course, the current waypoints are rather simple. So feel free to create a more complex route like this one:

Pinky, Inky and Clyde

We don't want Blinky to feel lonely in there, so let's repeat the same work flow for

Note: it's important that we use different waypoints and movement speeds for each ghost in order to make the game

more challenging.

If we press Play then we can now play a nice round of Pac

again and then drag one waypoint after another into the Waypoints

then we can see how Blinky moves along the waypoints:


We don't want Blinky to feel lonely in there, so let's repeat the same work flow for Pinky, Inky


then we can now play a nice round of Pac-Man:

Waypoints slot of


and Clyde:


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