MiniGame1: GrandPrix Monaco
***************************

You will:
	
	* How to find information
	* Manage Input
	* Control a car by translation/rotation
	* Snap vertex
	* Create a chase camera
	* Build a track
	* End the race using a finish line


How to search
=============

 

Suppose you want to know how to rotate an object, 
here are some of the simplest and most efficient methods:


.. hint::

	.. image:: google.png
		:scale: 30%
	
	* If you do not know the name of the function, ask for **how to rotate in unity**
	
	* If you already know the function name: ask for **Unity Rotate**
	
	 
			
	.. image:: visual.png
		:scale: 40%
	
	* With IntelliSense - Autocomplete

	* Type: **Rotate(**
	
		.. image:: intelli1.png
			:scale: 70%
		
	* Use up/down arrows to see the different options
		
	.. image:: gpt.png
		:scale: 50%
	
	* Please ask for **how to do it, not just to do it**
	
	* Fore example:  **Rotate in unity using c#**
	
	.. image:: youtube.png
		:scale: 40%
	
	* Outside of a specific topic, watching a 15-minute video to find an answer that only takes 10 seconds to explain is quite time-consuming.
	 
 

Refresher
=========

How to manage your view:
	
		* F key: center an object.
		* Right-click: look around.
		* ALT + Left-click: rotate camera while focusing on the selected object.
		* ALT + Right-click: zoom in & out.
		* Mouse wheel: zoom in & out.
		* Hold mouse wheel + mouse move: pan.
				
				
Car Controls
============


Scene Layout
------------

	* In the Assets folder, create a new folder named *MiniGames*
	
	* Inside this folder, create a new Scene named: *Ultimate Race*

	* Using 3D Cubes:
	
		* Create a road of 50mx10m
		* Create a car 4mx2mx1m
	
		.. image:: scene.png
			:scale: 70%
			 
			 
	* Adjust your camera so the entire scene is visible in Play mode.
	
	
			
Input.GetAxis()
---------------

Unity combines both keyboard and joystick inputs through the **Input** utility class. By using the  function GetAxis("Horizontal"), we retrieve information about horizontal movement from either the arrow keys or/and the joystick. 


	* Create a new script and attach it to the car
	* Set its name to *CarControler*
	* Paste the following code
	
	
	.. code-block:: csharp
		
		using UnityEngine;

		public class carControler : MonoBehaviour
		{
			void Start() { }

			void Update()
			{
				float v = Input.GetAxis("Horizontal");
				Debug.Log(v);
			}
		}
		
	* Enter Play mode
	* Use the left and right arrow keys and observe the values returned by the *GetAxis* function.

		
		.. image:: joy.png
			:scale: 40%
			
	.. note:: Unity seems to simulate joystick behavior through keyboard keys. For example, when we press the right arrow key, Unity smooths the return values from 0 to 1.
		
Physic's law
------------

In unity, rotations use degrees. We recall the formula that gives the rotation angle based on the rotation speed and the time interval:

.. math::

   angle = dT \times Rot_{speed}


 

Let's turn
----------

We want to make our vehicle rotate at a maximum speed of 30°/sec.

	* Add a public float variable **turnSpeed** in your script
	
	* In the update() function, add these lines:
	
		.. code-block:: csharp	
	
			float dt =  Time.deltaTime;
			float hInput = Input.GetAxis("Horizontal");
			transform.Rotate( ... );
	
	* Check the documentation of the *Rotate* function
	* Using a simple operation, make it so that:

		* When input is 0, nothing happens
		* When input is 1, the vehicle turns at the speed *turnSpeed*
	
	
	.. image:: rot.gif
			:scale: 60%
	
	.. dropdown:: Help in case nothing works
		:animate: fade-in

		 		.. code-block:: csharp
				
					using UnityEngine;

					public class carcontrol : MonoBehaviour
					{
						public float rotSpeed;

						void Start() { }

						void Update()
						{
							float dT     = Time.deltaTime;
							float hInput = Input.GetAxis("Horizontal");
							transform.Rotate(Vector3.up, rotSpeed * dT * hInput);
						}
					}


Go forward
----------

We want our vehicle to drive at a maximum speed of 30m/s.

	* Add a public float variable **maxSpeed** in your script
	
	
				
	* When the player press the up arrow key, the vehicle must go forward at the speed *maxSpeed*

	  

	.. image:: go.gif
		:scale: 60%

Buid a track
============

	* Select the piece of road in the scene
	* Duplicate it and move it away
	* In the Inspector, change its Y-value for 30°
	* Snap it to the end of the road
	
		.. image:: track.gif
		
	* Add multiple pieces to build a small track
	
	
		.. image:: fulltrack.png
			:scale: 70%
			
 
 
Chase camera
============

We want the camera to follow the vehicle
 
 
	.. image:: finalcar.gif
		:scale: 60%
 
 
	* In the Hierarchy, drag and drop the camera into the car GameObject
	
		* The camera becomes a child object of the car in the Hierarchy
		
		* This way, when the car moves, the camera automatically follows
	
		.. image:: child.png
				:scale: 40%
	
	
	* Reset the camera transform node
	
		.. image:: reset.png
			:scale: 50%
	
	* Activate camera preview
	
		.. image:: campreview.png
			:scale: 50%
	
	* Select translate tool
	
	* Move the camera to position it above the car's roof with a downward view
	
		.. image:: preview.png
			:scale: 50%
		
		
Finish line
===========

	* Create a finish line
	
		.. image:: finish.png
			:scale: 50%
			
	* Create a collider with a script to detect when the car passes between the two poles
	
		* Change the color of the banner from red to green
		
Add more fun
============

As you may have noticed, the car doesn’t fall when it goes off the track.
To make things more fun and a bit more challenging, we’re going to simulate gravity.
We’ll give a brief overview of the process here, as it will be covered in more detail in an upcoming chapter.

	* Select the Car GameObject
	* In the Inspector, click the *Add Component* button
	* Add a *Rigidbody* component
	* In the *Rigidbody* settings, make sure the *Use Gravity* option is enabled
	
	* Enter Play mode and have fun !
	
	.. image:: fun.gif