This is the last part for this project . In this part we are going to build the complete game.

Till now we have played the game inside our unity editor, To export to our required platform ,it should be a executable. file format , eg  exe for windows, .deb for linux.. apk for android .. etc

This process of making executable format of our game is known as building.

For that click File -> then build settings,

Note , if you are coming directly to this part of the tutorial ,without going to the previous one, click on the Add open scenes , this is how you add your scenes to the build , if you don't add a scene , unity will ignore that scene and will not be available in the final game.

Now you will be able to see some options , including which platform you want to build for, by default modules for building windows , linux , mac  executable will be installed along with unity. if you want to build for other platforms like android or webgl , you have to download and install those modules.Links for those modules can be found by clicking on the required platform and click open download page. 

note that if you are building for other platform , After downloading and installing those modules. you need to select the platform and click the "switch platform" to take effect.

Also changing platform in-between requires you to re-import the assets which requires a lot of time.so it is recommended to switch your platform at the beginning of the development process itself.

Player Settings:

This include some of the setting for you build . click it and you will be able to see a new tab

If you are building for pc,it is not essential that you configure these setting, even if you build with default value there won't be any error,  but for some platforms like android these configurations are very important and can cause error if not properly configured . 

1. First you have some details about the product , you company ,version , just fill it.

2.Default icon is the icon of you executable file. to change that drag any image to your project files. and then drag it to the icon .

3. next is the cursor , which if left empty will use the default windows cursor.

next important part is inside under " Resolution and Presentation" click on it to expand it.

1. in this you can change the screen mode ie full screen , windowed...  if you chose windowed you will be allowed to give the default resolution (resolution which your game starts).

Next is under Splash screen:

In this post we are trying to set up the script in such a way that the unity would consider collision only when our player hits the vehicle this is because ,till now our script is in such a way that it would consider collision if any other object collides with the vehicle , so even if there is collision between two vehicle unity would consider it as a collision and prints "hit".

To fix that, we modify the "vehicle.cs" script in such a way that when the collision occurs it will check if the name of the collided object is our player name then only it would consider as a collision.

to do that we add a "Collider " variable in our OnTriggerEnter()  Function ,so it becomes : OnTriggerEnter(Collider xyz). 

Now the colliding object is stored in the xyz variable.and next is to check if its name is same as our players.

{ Note that we have removed the "Hit "printing function}

For that we use if statement, which compares if the name of that collider is "Chick"

which will be like:

if(xyz.name=="Chick")
{

//runs these code only if the above condition is true

}

so our vehicle.cs script becomes:

Now if you consider the original game , it will be like a when it collides . it pause the game and asks for what to do next like "go to main menu, restart etc." but for simplicity what we do is just reload the game.

Reloading Game:

Even though i have said "Reloading Game" , it is not the complete game which reloads , instead it one particular scene that reloads. Actually there no reload function available in unity instead what we  does is , we load the same scene again.So our scene changes its state to the initial state .

The use of scene method helps developers to reduce the complexity of the level design , ie each level(/ scene) can be designed separately and  loaded using scripts. And this can be seen in many game like , GTA San Andreas, where you will see a break when entering into a building, what's happening behind is that outside environment is removed from the memory and the inside environment is loaded into the memory.

 Loading scene :

Before writing functions for loading scene , note that these functions are currently not available in our script , because if you check the script , you will find that only " using UnityEngine; "is written , what gives us only the essential unity tools / functions. To avail scene management functions/tools we must explicitly mention it like:

using UnityEngine.SceneManagement;

Note that this is an extra line of code added to the script.So don't remove "using UnityEngine;"

Now we have the scene management tools available in our script.

To load scene we use:

SceneManager.LoadScene("SampleScene");  inside the if statement .

where "SampleScene" is the name of our scene , which is the name of the scene file you saved.

you will also able to find the name from the top window bar:

and now our full script will be like:

Now if you save and go to unity , you will be able to see that your game will reload if your player collides with the car.

And it doesn't consider the collision between vehicle.

Also note that there is a chance that you may face an error about the Scene ,For our version it is not showing error , if you are facing that error ,what you should do is to add your scene to the build scenes,

Adding scene to build:

Go to File: ->   Build Settings - Add open Scenes

And that should fix it.

Next we will be adding vehicles to multiple lanes of road , before that you might seen that our vehicle collides with the player and outputs "Hit" even if they are not on the same lane , this is because one of our collider is little bit big compared to the original shape. for me it was the vehicle which caused the problem. if you don't have this problem you can skip this step. 

To fix that adjust the size value in the box collider attached to the vehicle , such that its width is less than the size of the lane. it is ok even if it is inside the vehicles body.Also you can click edit collider button in the collider component and some small green squares will appear on the faces of the collider , click and drag them to adjust the collider size.

{if you are not able to see the collider in the scene , it because you have hide it in the inspector , just click on the expand icon (marked in the figure) to show it.}

now if you try to play you will see that the problem has been fixed and does not collide if the player character is near to the vehicle.

So now we can add more vehicle.

For that ,similar to how we have create the previous vehicle , do the following steps:

• Drag the next 3d file of the vehicle to the scene
• Adjust the position ,rotation and scale if needed .it is not necessary that you need to place ,it on the next lane instead you can place it little bit behind the already existing car so that it feels like traffic on that lane , but make sure that when you add the script, velocity and time interval are set such that both vehicles doesn't collide{ for example ,you can set both of the same velocity and time interval for both ,so that they don't collide.} 
• Next is to add a Rigidbody to it(make sure that new object is selected -> "Add component" in the inspector ->type"Rig"->select Rigidbody)
• Uncheck the use Gravity in the rigid body.
• Add Box collider (make sure that new object is selected -> "Add component" in the inspector ->type "box" ->Select Box Collider)
• Adjust the box collider size , as mentioned in the above section.
• Mark "Is trigger" in box collider
• Next add our script ( click add component in the inspector- > type the name of the script {mine was vechicle.cs } -> select it)
• Now set the time velocity , i paced my car such that it moves in opposite direction in the next lane so my velocity is (0,0,1)
•  
  
  
  
• Now give value for time interval , i gave  10 , you can give random values to vehicles that it would feel like real traffic. Also you can add vehicle behind one another .

if you play now . when your car hits the player it stops, because it velocity was changed to zero.

But If you analyse the game , actually there is no need for collision , instead we need only an output saying the vehicle hit the chicken . 

So to do that what you have to do is check the Is Trigger in the collider of the vehicle.

What this does is that , Now the vehicle will not collide instead it will call a function( a particular block of code ) when it collides with other object. So that now we can run any code as we required when the two objects meet.but instead of doing any complex task we will just print "Hit" to the console tab.

so note that this function can be written inside any script attached to it.And we are writing it inside the vehicle script.

the name of that function is OnTriggerEnter() , which will be called at the frame when the player enters the vehicle collider.

And the final code will be like:

inside OnTriggerEnter we have written Debug.log("Hit"); so that when ever the player hit the vehicle "Hit" will be output on the console tab.

Save and try it on the game.

Now next , we need to reset the position of our vehicle after some time so that it loops continuously .for that what we do is that 

first during the start we save the initial position to a variable.

then we declare two other variables ( tmint,temptm ) for the time interval and other for saving the current time

during each update

we compare if the current time is greater the previously set time . if so we will get the next set time as current time + time interval..And run a following task ( ie reset our vehicle position and velocity ) so that this task will be repeated after every time interval.

Now the vehicle code be like:

Now if you save and go to unity editor you will see Tm_interval and Nexttm under the vehicle script component in the inspector tab. set value only for Tm-interval , since NextTm is calculated automatically. for me my car need to reset at 5 sec so mine was 5 forTm-interval.

Now if you play you will be able to see you car resets after the time interval .

In this session we are going to add vehicles,

for that first drag any vehicle 3d file from the project tab.

next we need to make the vehicle move for that a single line of code is enough. So create a script with name vehicle :

this is the code you have to add 

this.GetComponent<Rigidbody>().velocity= new Vector3(0,0,1f);

what this does it that during the starting of the game , the script will try to get a rigidbody component from the Gameobject we add it to . this is because the velocity of a game object can only be accessed from a rigidbody.

If it finds the rigidbody component it will assign a new given value to the velocity of that object.

since we need to assign different values for velocity instead of directly giving value , we create a variable called vel. which we will give values from the unity editor

public Vector3 vel;

Save the script and go back to unity , And now if you have not added script to the vehicle  , do it by dragging it to vehicle. now you will be able to see val in the inspector . give it a value since i plan to move this in z direction according to my game I give values    x=0,y=0,z=1.

But if you click play now. you will get an error because, as mentioned above our script will search for a RigidBody in our gameObject( here vehicle) , but it doesn't have one. So add one , {click "Add component" on inspector tab while selected vehicle object and type RigidBody (Not RigidBody2D ) select the Rigid Body shown there.}

And it will be added to your object. By default when ever you add rigidbody, gravity is enable. So our car moves down, which we don't want . So disable it by unchecking the Use Gravity in rigid body.

Now if you play the game our vehicle moves and we can move our character. 

Next step is to make the camera follow our chicken.

To do this we use a simple script, you can find it from this video:

if you notice you can see that the last line mentioned in the video has been remove . Its because , in our game rotation is not so important.Also since our character movement is very quick , it feels like the camera tries to snap every time your character tries to move .So it feel better without it.

 Also our camera view is totally different from the game displayed in the video .So for our game what you have to do is, Don't change position of our camera according to the video. instead , just add the script to our camera.(our camera's position and rotation will be such that it will be able to view our character. as we have done in the previous post). Now in the script component you will see there are some parameter which were mentioned in the video 

First , target is our character , so drag our character to that field

Next is smooth speed , you can use trial and error method to find a suitable value for that. For me it was 0.05.

Next is offset , this is the distance your camera should keep from the target. which is the difference between current position of our camera and game character. If your character is near to origin , this value is same as the position of your camera, so copy each value of position to the respective axis field in the script component.

Now my script component values look like :

---------------------------------------------------------------------------------------------------------------------------

 Note that i doesn't own any copyright over crossy road or on any of the materials related to it. So even though i created the assets these doesn't belong to me. If you are publishing this game ,It is your responsibility to get appropriate permission from the corresponding developers.

Now we need to move our character

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    
    void Start()
    {
        // you write here what should be done before game start. and it runs only once

    }

    
    void Update()
    {
        // you write here what should be done in every frame and it runs multiple times
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        
    }

    // Update is called once per frame
    void Update()
    {
        if(Input.GetKeyDown(KeyCode.UpArrow)) // runs the below block only if the GetKeyDown is true
        {

        }
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        
    }
    // Update is called once per frame
    void Update()
    {
        if(Input.GetKeyDown(KeyCode.UpArrow)) // runs the below block only if the GetKeyDown is true
        {
            transform.Translate(new Vector3(1,0,0));
        }
    }
}

Now click the play button and check if our player is moving. it should , if not make sure you have done the above step. if you are still not able to move contact me, i will help you fix it.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        
    }
    // Update is called once per frame

    public Vector3 move;
    void Update()
    {
        if(Input.GetKeyDown(KeyCode.UpArrow)) // runs the below block only if the GetKeyDown is true
        {
            transform.Translate(move);
        }
   }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        
    }

    void Update()
    {
        if(Input.GetKeyDown(KeyCode.UpArrow)) // runs the below block only if the GetKeyDown is true
        {
            transform.Translate(new Vector3(0,0.2f,0));
        }
    }
}

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Controller : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        
    }

    void Update()
    {
        if(Input.GetKeyDown(KeyCode.UpArrow)) // move up
        {
            transform.Translate(new Vector3(0,0.2f,0));
        }

        if(Input.GetKeyDown(KeyCode.DownArrow)) // move down
        {
            transform.Translate(new Vector3(0,-0.2f,0));
        }
        
        if(Input.GetKeyDown(KeyCode.LeftArrow)) // move left
        {
            transform.Translate(new Vector3(0.2f,0,0));
        }
        
        if(Input.GetKeyDown(KeyCode.RightArrow)) // move right
        {
            transform.Translate(new Vector3(-0.2f,0,0));
        }

    }
}

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