I Want My Auto Moving Car To Get Affected By Gravity - c#

So I'm doing a game where the car automatically moves so whenever the car hits an object it continues floating in the air going forward without begin affected by gravity so that was my main code, I'm still kinda new to this :\
void Update()
{
transform.Translate(Vector3.forward * Speed * Time.deltaTime);
}
then I tried adding this to my code
void Start()
{
coll = GetComponent<Collider>();
coll.isTrigger = true;
}
// Disables gravity on all rigidbodies entering this collider.
void OnTriggerEnter(Collider other)
{
if (other.attachedRigidbody)
other.attachedRigidbody.useGravity = true;
}
but it's still not affected by this whatever I do it just doesn't work an continuously keeps going forward can you help me fix this problem I'm nearly done on that game so if you could help me I'd be very Thankful <3
Note:The car have RigidBody and is affected by gravity and have a huge mass but this doesn't affect any

Also make sure isKinematic is set to false.
void OnTriggerEnter(Collider other)
{
other.attachedRigidbody.useGravity = true;
other.attachedRigidbody.isKinematic = false;
}
void OnCollisionEnter(Collision col)
{
if(col.collider.CompareTag("taghere") || col.collider.name == "Name")
{
// you have to mention the script in which rigidbody you want to disable
}
}

When you add a rigidbody to a gameobject you are effectively handing over direct control of the translation to the rigidbody, and you should no longer alter the transform directly.
The easiest way would be to set the velocity of the plane you want to move in only
void FixedUpdate(){
rigidBody.velocity = new Vector3( speed.x, speed.y,rb.velocity.z);
}

Related

friction not working correctly in my 2d game - unity

I am developing a 2d game in unity, and I am trying to add friction to slow the player down when he is on the ground. I launch the player into the air with the rigidbody's add force. I have heard of physics materials, and am currently trying to use them. I am using the 2d version of them, I made one material which had high friction. I add the material to the floor, and then I play the game, and my character is still sliding on the floor. I thought the problem might be with the player not having a physics material, so I added one. It still didn't work.
I tried doing different combinations with the different materials.
I tried attaching a rigidbody, but kinematic to the floor.
I tried looking it up, and couldn't find an answer.
Here is the code that moves the player:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Player : MonoBehaviour
{
public bool isGrounded = true;
public float fireForce;
Rigidbody2D rb;
void Start()
{
rb = GetComponent<Rigidbody2D>();
camera = camObj.GetComponent<Camera>();
}
void Update()
{
RotateToPoint();
Fire();
}
void OnCollisionEnter2D(Collision2D obj)
{
if (obj.gameObject.tag == "surface")
{
isGrounded = true;
}
}
void OnCollisionExit2D(Collision2D obj)
{
if (obj.gameObject.tag == "surface")
{
isGrounded = false;
}
}
void Fire()
{
if (Input.GetKeyDown(KeyCode.Mouse0) && isGrounded)
{
rb.AddForce(transform.up * fireForce, ForceMode2D.Impulse);
}
}
}
I do not know if I am approaching the problem correctly. If I am not, does anyone know how to avoid slippery game objects. Any help would be appreciated.
Adding a higher angular drag was the solution to my problem. Angular drag is what slows the object down along its rotation. Friction may not always be the problem.
Notice the two highlighted variables. You might want to raise these values (I changed angular drag from its default) to something higher. Adding the physics material might help, you should try this if this first solution doesn't work.
The problem here is that you are not limiting the velocity of the player, so what you can do is set an if statement if the player is touching the floor and the velocity is higher than what you want it to be.
Example:
void FixedUpdate()
{
if (isGrounded == true && rb.velocity.x > 1 || isGrounded == true && rb.velocity.z >1)
{
rb.velocity = Vector3.zero;
rb.angularVelocity = Vector3.zero;
}
}

OnCollisionStay not working in 2D movement script

So, I'm still not the best at this but I'm trying to use this script for 2D movement but the jumping isn't working for some reason. It keeps saying that the OnCollisionEnter function "is declared but never used". Can someone tell me what im doing wrong? Thanks
If I remove the (Collision col) part it says that "void cannot be used in this context".
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class RonyWalking : MonoBehaviour
{
Rigidbody2D rigid;
SpriteRenderer sprite;
public bool isJumping;
public float spd = 2.0f;
// Start is called before the first frame update
void Start()
{
rigid = GetComponent<Rigidbody2D>();
sprite = GetComponent<SpriteRenderer>();
}
// Update is called once per frame
void Update()
{
if(Input.GetKey("d")){rigid.velocity = new Vector2(spd, 0);}
else if(Input.GetKey("a")){rigid.velocity = new Vector2(-spd, 0);}
if(Input.GetKeyDown("w") && isJumping == false)
{
rigid.velocity = new Vector2(0, 5);
isJumping = true;
}
void OnCollisionStay(Collision col)
{
isJumping = false;
}
}
}
When using 2D physics, you need to use the 2D lifecycle methods;
void OnCollisionStay2D(Collision2D col)
{
isJumping = false;
}
And you shouldn't put this method inside your Update method... It should be on class level:
public class RonyWalking
{
void Update()
{
// ...
}
void OnCollisionStay2D(Collision2D col)
{
// ...
}
}
Don't worry about "Is declared but never used", this may be because you don't have specific code referencing the method, but Unity will raise events that calls it, "automagically"
Another thing that I can see while reading your code, that may be unintentional behaviour for you, is that when clicking left/right, you set velocity UP to 0, and when clicking up you set LEFT/RIGHT velocity to 0; this will result in freezing the movement mid-air if you jump, then move while in air:
Click D; velocity = 2, 0
Click W; velocity = 0, 5
Character will now move upwards until another input is given
Click D; velocity = 2, 0 and the character will continue moving while in air because when moving sideways the up/down velocity is set to 0
To solve this, either set the other to existing velocity or make the inputs manipulate a Vector that you then apply at the end of the movement code:
Vector2 existingMovement = rigid.velocity;
if (Input.GetKey(KeyCode.D))
existningMovement.x = spd;
else if (Input.GetKey(KeyCode.A))
existningMovement.x = -spd;
if (Input.GeyKeyDown(KeyCode.W) && !isJumping)
{
existningMovement.y = 5f;
isJumping = true;
}
Furthermore, I think you may have some unexpected behaviour with OnCollisionStay; it will fire every frame that you're colliding with the ground, I assume. But I think it may also fire a frame or two AFTER you've jumped since the physics of your character will not INSTANTLY leave the collision, so isJumping will be set to false even after your jump, letting you jump while in the air one more time.
I would recommend that you use OnCollisionExit2D(Collision2D col) to set isJumping = true instead, or OnCollisionEnter2D(Collision2D col) and set it to isJumping = false, depending on the functionality you desire (if you want the ability to jump after walking out of a cliff)

Unity 2d game movement script issue - unable to jump

So basically, after hours of torment trying to create basic movement script for simple platformer game I succeeded, but not quite. Square character is able to move around and jump just ok, but sometimes it won't jump, usually while moving on short distances or, rarely, standing in place and trying to jump. I can't figure out how to fix that. Here is entire script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerMovement : MonoBehaviour {
private Rigidbody2D rgdb2;
public float movementSpeed;
public float jumpHeight;
private bool isJumping = false;
// Use this for initialization
void Start ()
{
rgdb2 = GetComponent<Rigidbody2D>();
}
// Update is called once per frame
void FixedUpdate ()
{
float moveHorizontal = Input.GetAxis("Horizontal");
HandleMovement(moveHorizontal);
if (Input.GetKeyDown(KeyCode.Space) && isJumping == false)//by typing Space player jumps, cant double-jump
{
rgdb2.AddForce(new Vector2(rgdb2.velocity.x, 1 * jumpHeight), ForceMode2D.Impulse);
isJumping = true;
Debug.Log("jumped");
}
}
private void HandleMovement(float moveHorizontal)//applying player horizontal controls and customing player's speed by movementSpeed variable
{
rgdb2.velocity = new Vector2(moveHorizontal * movementSpeed, rgdb2.velocity.y);
}
private void OnCollisionEnter2D(Collision2D coll)
{
if (coll.transform.tag == "Platform") //if player is touching object with Platform tag, he can jump
{
Debug.Log("on ground bitch");
isJumping = false;
}
}
}
It may not be that important, but I want to polish this game as much as possilble, even if I don't need to, since it's basically my first game made in Unity3d with C#.
An important thing to keep in mind: Unity3D Engine's inputs are only updated during the time the engine calls Update() methods for your GameObjects.
What this means is that you should not read any type of input in the FixedUpdate() method. Methods like GetKeyDown() and other methods from the Input class which read keyboard/mouse/axis buttons/values should not be called during FixedUpdate(), as their returned values are unreliable.
Due to this, what is probably causing your jump implementation to fail is that the GetKeyDown() method you're calling in FixedUpdate() is returning inconsistent/invalid (false) results, when the user presses the jump key.
Fixing this can be quite simple. I suggest you keeping a boolean variable which keeps track of whether the jump key has been pressed, and gets its value updated during Update(). This should fix your problem.
bool jumpKeyPressed;
private void Update()
{
if (Input.GetKeyDown(KeyCode.Space))
jumpKeyPressed = true;
else if (Input.GetKeyUp(KeyCode.Space))
jumpKeyPressed = false;
}
private void FixedUpdate()
{
/* Update "moveHorizontal", call HandleMovement(...) here, as you've already done. */
if (jumpKeyPressed && isJumping == false)
{
// IMPORTANT: this prevents the "jump force" from being applied multiple times, while the user holds the Space key
jumpKeyPressed = false;
/* Remaining jumping logic goes here (AddForce, set "isJumping", etc) */
}
}
It's because your logic for jumping is inside FixedUpdate()
When you use GetKeyDown to register input make sure to use Update instead because if you press the key using FixedUpdate it may or may not run during that frame, test it with Update instead.
You already have in comments how Update works, it is called every frame but FixedUpdate according to Unity documentation: This function is called every fixed framerate frame
void Update ()
{
float moveHorizontal = Input.GetAxis("Horizontal");
HandleMovement(moveHorizontal);
if (Input.GetKeyDown(KeyCode.Space) && isJumping == false)//by typing Space player jumps, cant double-jump
{
rgdb2.AddForce(new Vector2(rgdb2.velocity.x, 1 * jumpHeight), ForceMode2D.Impulse);
isJumping = true;
Debug.Log("jumped");
}
}

Use AddForce to knock back Player after contact with Enemy

I'm working on my very first Unity game. It's still in prototype and will be very simple anyways, consisting of a cube as the player and spheres as enemies.
I'm trying to write a code with AddForce to knock the player a pretty good distance in an arc in the direction opposite of the enemy when they come in contact, but I still have a primitive understanding of how to use AddForce and can't seem to get force applied in any direction at all. The player just moves through the enemy.
Here's the only thing I could manage to scrap together and it is obviously insufficient:
if (other.gameObject.tag == "Enemy")
{
playerDead = true;
Rigidbody rigidbody = other.GetComponent<Rigidbody> ();
rigidbody.AddForce (transform.forward * 100);
}
I can post a screenshot if it helps.
Instead of transform.forward, use a more tailored direction depending on the position of both units
public float speed = 100;
if (other.gameObject.tag == "Enemy")
{
playerDead = true;
Vector3 direction = (transform.position - other.transform.position).normalized;
other.GetComponent<Rigidbody>().AddForce (direction * speed);
}
Edit: You must make sure that the rigidbody is on the game object calling the OnCollisionEnter function, it cant just be on any of the objects involved in the collision.
I cannot comment so I must make an answer.
You have an isTrigger set up apparenty. Be sure to turn isTrigger OFF or your player will walk through the enemy collider.
[SerializeField]
private float speed = 100;
private bool playerDead;
OnCollisionEnter(Collision collision)
{
if(collision.gameObject.tag == "Enemy")
{
playerDead = true;
Vector3 direction = (transform.position - collision.transform.position).normalized;
collision.GetComponent<Rigidbody>().AddForce (direction * speed,0,0);
//AddForce is a vector3 apparently and requires (x,y,z)
// Also note that I'm getting errors with the "collision.GetComponent<>"
// You're going to want to remove "collision"
// I think the smarter approach maybe to declare a public Rigidbody variable ( Up Top )
[SerializeField]
private Rigidbody playerRidg;
playerRidg = GetComponent<Rigidbody>().AddForce(direction * speed,0,0);
}
}
My solution using coroutine which toggles a bool "spikes":
Player collision:
private void OnTriggerEnter2D(Collider2D collision){
if (collision.gameObject.tag == "Spike" )
{
StartCoroutine(Knockback());
}
}
Coroutine:
IEnumerator Knockback()
{
spikes = true;
yield return new WaitForSecondsRealtime(0.3f);
spikes = false;
}
Whenever the spikes bool is true player will be moved
void FixedUpdate()
{
if (spikes ==true)
{
Vector2 NewPosition = new Vector2(10.0f, 10.0f);
moveCharacter(NewPosition);
}
}

Player stops moving upon contact with a gameObject

I am having my player constantly drop downwards on the screen and when the player interact with other gameobjects, I want to destroy those gameobjects and want the player to carry on dropping.
But the moment the player hits the other gameobject, the gameobject does gets destroyed but the player stops dropping. Please help advice what I am doing wrong.
//Script attached to player:
//x-axis movement speed
public float playerMoveSpeed = 0.2f;
//how much force to act against the gravity
public float upForce = 9.0f;
//horizontal control
private float move;
// Update is called once per frame
void Update()
{
//player left right x-axis movement control
move = Input.GetAxis("Horizontal") * playerMoveSpeed;
transform.Translate(move, 0, 0);
}
void FixedUpdate()
{
//to fight against the gravity pull, slow it down
rigidbody.AddForce(Vector3.up * upForce);
}
//Script attached to gameObject to be destroyed on contact with player
void OnCollisionEnter(Collision col)
{
//as long as collide with player, kill object
if (col.gameObject.tag == "Player")
{
Destroy(gameObject);
}
}
First one should solve your problem, the second one might make your life easier :)
1.) Mark the objects as "Triggers" so that no real collision happens. That way your player should just fall through and keep its speed. You also need to use OnTriggerEnter instead of OnCollisionEnter
2.) If you dont really need "forces" but just want to move the player constantly you could just turn off gravity and set rigidbody.velocity manually like(i am assuming 2d here):
void FixedUpdate()
{
horizontalVelocity = Input.GetAxis("Horizontal") * playerMoveSpeed;
rigidbody.velocity = new Vector3(horizontalVelocity, verticalVelocity, 0.0f);
}
Just play around with values for verticalVelocity and horizontalVelocity untill it feels right.
Also note that if you move something in Update() you should probably multiply the translation with Time.deltaTime or your player will move faster on higher fps. FixedUpdate is called in fixed time intervalls so you dont need it there(thats why its called Fixed Update).

Categories

Resources