{"id":1403,"date":"2020-05-23T10:49:42","date_gmt":"2020-05-23T01:49:42","guid":{"rendered":"https:\/\/www.munchou.com\/biwa-chan\/?p=1403"},"modified":"2020-05-23T10:49:42","modified_gmt":"2020-05-23T01:49:42","slug":"my-first-game-in-unity-part3-when-coding-isnt-innate","status":"publish","type":"post","link":"https:\/\/www.munchou.com\/biwa-chan\/?p=1403","title":{"rendered":"My first game in Unity part3 – When coding isn’t innate"},"content":{"rendered":"

Hi!<\/strong><\/p>\n

Third part of my first steps in Unity.
<\/strong>I guess you’re here because you want to know what I did to make my car brake? I’m about to show you my first code after hours (like, a lot of hours) of struggle to figure out how I can do thing and why the holy hell so many things I tried just didn’t work (although in those cases, I’m still not sure why).
Please remember I’m beginning, and that code is certainly not what you’d get from a pro.<\/p>\n

First of all, here is the complete code (so far), click the picture to get it full:
\"\"<\/a><\/p>\n

Now I’m going to describe each part the best way I can (hum…), the way I understood all of that.<\/p>\n

\"\"<\/p>\n

These are the functions (functions? – I don’t know yet how they are called) that are going to be used.
[SerializeField] private Vector3 _centerOfMass<\/em>: used to show and modify the center of mass (although I haven’t tried it yet in 2D mode, but it works in 3D physics) in the Inspector.
<\/em>(public float<\/em> means that we can change the value in the Inspector.)
public float speed<\/em>: used for the speed of the motor.
public float rotationSpeed<\/em>: used for the rotation of the car when in the air.
public WheelJoint2D<\/em>: used in the Inspector to assign the wheels’ Wheel Joint 2D<\/em> components.
private Rigidbody2D rb<\/em>: used as “rigid body”, to control the center of mass and rotation of the car.
private float movement<\/em>: used to assign the up and down-arrow keys, and trigger the movement of the car.
private float rotation<\/em>: used to assign the right and left-arrow keys, and trigger the rotation of the car in the air.
private float brake<\/em>: used to assign the up and down-arrow keys, and trigger the brakes.
private float nospeed<\/em>: used with brakes, to set the motor speed to 0.
private bool moveForward<\/em>: used to check whether the up-arrow key is pressed.
private bool moveBackward<\/em>: used to check whether the down-arrow is pressed.<\/p>\n

\"\"<\/p>\n

private void Start<\/em>
rb = GetComponent<Rigidbody2D>()<\/em>: assigned the component Ridigbody2D (which is the car) to “rb”.
rb.centerOfMass = _centerOfMass<\/em>: now that rb<\/em> is understood as the car, we get its center of mass.
void Update()<\/em>
movement = -Input.GetAxisRaw(“Vertical”) * speed<\/em>: the value of movement<\/em> will be the one of speed<\/em> (that I set to 4000) multiplied by 1 or -1, depending on which arrow key is pressed (up or down, considered as the vertical axis input).
brake = -Input.GetAxisRaw(“Vertical”) * nospeed<\/em>: same as movement<\/em>, but nospeed<\/em> is set to 0.1.
rotation = Input.GetAxisRaw(“Horizontal”)<\/em>: used to rotate the car when pressing the left\/right arrow keys (hence the “horizontal”).
moveForward = (Input.GetKey(KeyCode.UpArrow))<\/em>: set the value of moveForward<\/em> to the up arrow key.
moveBackward = (Input.GetKey(KeyCode.DownArrow))<\/em>: set the value of moveBackward<\/em> to the down arrow key.<\/p>\n

Okaaaay, we’re all set, now time to affect the car’s behavior!
First, when to activate the motor to make the car move.<\/p>\n

\"\"<\/a><\/p>\n

rb.AddTorque(-rotation * rotationSpeed * Time.fixedDeltaTime);<\/em>: the “formula” to make the car rotate when pressing right\/left arrow keys.
if (movement == 0f) {frontWheel.useMotor = false;}<\/em>: It means that when we’re NOT pressing the up\/down arrow keys, the motor is off.

<\/p>\n

After that, it comes to what happens when the up and down arrow keys are pressed. In each, there are 2 possibilities, depending on the speed on the car (velocity<\/em>).
The problem here is that it’s for sure the wrong way to do it<\/strong>, it’s only a workaround as I have no idea what to use to do it properly.
Ideally, the conditions should be set on the rotation speed of the front wheels, but so far I haven’t found anything. Whereas in my case, it’s the speed of the whole car as an object. Moreover, it’s very approximate, as you can see, because I set values to the velocity (-1, -0.5, 0.5, 1) that I chose randomly, but it works! As a beginner, I can’t complain, but I’m aware I’ve done it wrong.<\/p>\n

So depending on the velocity, the motorSpeed<\/em> changes either to normal (=driving), or to 0 (=braking). Again, it is faaaaar from being good: the motor’s speed is either at its maximum, or at 0, there is no smooth acceleration nor deceleration. Got to fix that too…<\/p>\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Hi! Third part of my first steps in Unity.I guess you’re here because you want to know what I did to make my car brake? I’m about to show you my first code after hours (like, a lot of hours) of struggle to figure out how I can do thing and why the holy hell […]<\/p>\n","protected":false},"author":1,"featured_media":1405,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[42],"tags":[],"_links":{"self":[{"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/posts\/1403"}],"collection":[{"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1403"}],"version-history":[{"count":13,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/posts\/1403\/revisions"}],"predecessor-version":[{"id":1427,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/posts\/1403\/revisions\/1427"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=\/wp\/v2\/media\/1405"}],"wp:attachment":[{"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1403"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1403"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.munchou.com\/biwa-chan\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1403"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}