Unity 5: Rigidbody 2d sticking to ceiling while velocity is moving upwards - c#

I am making a 2d game. My problem is that while playing, if the player holds jump and is under a BoxCollider2D, the player will not fall until they release jump.
My player GameObject consists of a sprite renderer, a dynamic rigidbody2d with gravity on and a boxcollider2d.
Here are my movement scripts:
1:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class JumpScript : MonoBehaviour {
[Range(1, 10)]
public float jumpVelocity;
[Range(0,10)]
public float speed;
private bool jumpQueue = false;
private bool boolin=false;
void Update()
{
//Friggin fall, loser
//Jumping
///*
if (Input.GetButton("Jump")&& GetComponent<Rigidbody2D> ().velocity.y==0)
{
GetComponent<Rigidbody2D>().velocity = Vector2.up * jumpVelocity;
}
//*/
//jumpQueue?
/*
if(Input.GetButtonDown("Jump"))
{
jumpQueue = true;
}*/
//Right Movement
if (Input.GetKey(KeyCode.D))
{
GetComponent<Rigidbody2D>().velocity = new Vector2(1*speed, GetComponent<Rigidbody2D>().velocity.y);
boolin = true;
}
if(Input.GetKeyUp(KeyCode.D))
{
GetComponent<Rigidbody2D>().velocity = new Vector2(0, GetComponent<Rigidbody2D>().velocity.y);
boolin = false;
}
//Left Movement
if (Input.GetKey(KeyCode.A))
{
GetComponent<Rigidbody2D>().velocity = new Vector2(-1*speed, GetComponent<Rigidbody2D>().velocity.y);
boolin = true;
}
if (Input.GetKeyUp(KeyCode.A))
{
GetComponent<Rigidbody2D>().velocity = new Vector2(0, GetComponent<Rigidbody2D>().velocity.y);
boolin = false;
}
//No movement?
if (Input.GetKey(KeyCode.D) && Input.GetKey(KeyCode.A))
{
GetComponent<Rigidbody2D>().velocity = new Vector2(0, GetComponent<Rigidbody2D>().velocity.y);
boolin = false;
}
//Time to handle animation, boios.
Rigidbody2D rb = GetComponent<Rigidbody2D>();
bool schwomp = false;
bool schwift = false;
if(rb.velocity.y>0)
{
schwomp = true;
}
if(rb.velocity.y<0)
{
schwift = true;
}
Animator anim = GetComponent<Animator>();
if (boolin)
{
anim.SetInteger("Boolin", 1);
/*if (!anim.GetBool("expand"))
{
anim.SetBool("expand", true);
anim.Play("running");
}*/
}
else
{
anim.SetInteger("Boolin", 0);
/*
if(anim.GetBool("expand"))
{
anim.SetBool("expand", false);
anim.Play("Idle");
}*/
}
if(schwomp)
{
//anim.SetInteger("Boolin", 2);
}
if(schwift)
{
//anim.SetInteger("Boolin", 3);
}
}
}
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class BetterJumper : MonoBehaviour {
public float fallMultiplier = 2.5f;
public float lowJumpMultiplier = 2f;
Rigidbody2D rb;
void Awake()
{
rb = GetComponent<Rigidbody2D>();
}
void Update()
{
if(rb.velocity.y<0)
{
rb.velocity += Vector2.up*Physics2D.gravity.y*(fallMultiplier-1)*Time.deltaTime;
}
else if(rb.velocity.y>0&&!Input.GetButton("Jump"))
{
rb.velocity += Vector2.up * Physics2D.gravity.y * (lowJumpMultiplier - 1) * Time.deltaTime;
}
}
}
Thank you so much in advance!

You're using Input.GetKey() which will poll the key every frame. This means more and more velocity is added the longer you hold jump. You've effectively built a jetpack rather than a jump force.
You should use Input.GetKeyDown() which will only fire once when a key is pressed down, then has to be released and pressed again in order to re-trigger. You then need to apply a single sufficiently strong vertical force using RigidBody.AddForce() to make the character jump, rather than adding continuously to the velocity.
Additionally, you should really be caching the result of your GetComponent<Rigidbody2D>() call when the script either wakes up or starts so that you're not calling it continuously; Each one of those calls takes processing time. Also, you should be using FixedUpdate() for physics.
public class ExampleClass : MonoBehaviour {
public float thrust;
public Rigidbody rb; // make the rigidbody variable available anywhere in the class
void Start() {
// cache the rigidbody component to the variable once on start
rb = GetComponent<Rigidbody>();
}
void FixedUpdate() {
// use the variable reference from now on rather than making GetComponent calls
rb.AddForce(transform.up * thrust);
}
}

Soviut's answer explains it quite nicely, but there's more that you need to know. You're directly manipulating the velocity, which overrides the effect of any forces, including gravity(despite the fact you're applying it manually). See the documentation.
As demonstrated in Soviut's answer you should be applying forces and impulses, letting the physics engine determine the velocity. The only time you should set velocity directly is when you're building a simulation that intentionally has unrealistic physics(i.e. retro platformers). Even in that case, bear in mind that doing so creates a lot more work, because you'll need to factor in every little thing that creates movement. This means you're essentially re-inventing the physics engine.

Related

How to prevent speeding of rigidbodies used to control characters

I have a player in unity with the movement controlled by a rigidbody. The movement on the Z axis is kept contstant by the game to keep the player moving forward. However, this means that the rigidbody keeps speeding up so its speed at the start of the game is much slower than the speed at the end of the game. Here is my script:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.InputSystem;
using UnityEngine.SceneManagement;
public class Controller : MonoBehaviour
{
[Tooltip("Rigidbody component attached to the player")]
public Rigidbody rb;
public float forwardMax;
public float slowBy;
private float movementX;
private float movementY;
private float gravity = -9.81f;
private bool isJumping = false;
private bool isSlowing = false;
private bool isSpeeding = false;
private float speedX = 100;
private float speedY = 150000;
private float speedZ = 60;
// Start is called before the first frame update
void Start()
{
rb = GetComponent<Rigidbody>();
}
void Update()
{
// if(!controller.isGrounded)
// {
// Vector3 gravityVector = new Vector3(0.0f, gravity, 0.0f);
// rb.AddForce(gravityVector * Time.deltaTime);
// }
}
void OnCollisionEnter(Collision collision)
{
// SceneManager.LoadScene(1);
}
// Update is called once per frame
void OnMove(InputValue movementValue)
{
Vector2 movementVector = movementValue.Get<Vector2>();
movementX = movementVector.x;
movementY = movementVector.y;
}
void OnJump()
{
isJumping = true;
}
void CalculateMovement()
{
if(rb.velocity.z > 20)
{
rb.drag = 20;
}
else
{
rb.drag = 0;
}
Vector3 movement = new Vector3(movementX * speedX, 0.0f, speedZ);
if(isJumping)
{
movement.y += Mathf.Sqrt(speedY * -3.0f * gravity);
isJumping = false;
}
rb.AddForce(movement);
Debug.Log("Speed is " + rb.velocity.z);
}
void FixedUpdate()
{
CalculateMovement();
}
}
Is there a way to keep the forward velocity constant? The problem is worse when the player jumps.
First I tried clamping the forward (z-axis) vector but that had no effect. Then, I tried adding a backward vector onto the total when the forward velocity was above a certain number but this led to it speeding up and slowing down all the time. Then I tried the same thing with the drag on the rigidbody but that had the same effect.
You can use rigidbody.velocity and set it to constant value or whatever you want instead of adding force. By adding force, your character's speed increases.
Also you can use AddForce but you have to tune the force value dynamically according to the current velocity.
rigidbody velocity
How about directly setting the z value you want at the end of FixedUpdate() ?
......
void FixedUpdate()
{
CalculateMovementWithoutZMovement();
rb.velocity = new Vector3 (rb.velocity.x, rb.velocity.y, ConstantZValue);
}

Collision update is one physics update late, and it caused object to cancel its velocity

I have a character, he can move and jump. I need to check if it is grounded, so I made a trigger box collider as a characters component, and I use OnTriggerEnter and OnTriggerExit to check if it is grounded, but the exit of collision with object that the character is standing on is detected one physics update late, and when it is detected, the upward velocity appears to become 0, and the character starts falling. Here is my code:
using System.Collections;
using UnityEngine;
public class Player : MonoBehaviour
{
public float speed = 4.0f;
public float jumpSpeed = 8.0f;
private bool doJump = false;
private Rigidbody rb;
bool isGrounded = false;
private float x, z;
private void Awake()
{
rb = GetComponent<Rigidbody>();
}
private void Update()
{
x = Input.GetAxis("Horizontal");
z = Input.GetAxis("Vertical");
if (Input.GetKeyDown(KeyCode.Space))
{
StartCoroutine(Jump());
}
}
void FixedUpdate()
{
if (isGrounded)
{
//this is movement
rb.velocity = (transform.right * x) * speed * Time.fixedDeltaTime + (transform.forward * z) * speed * Time.fixedDeltaTime;
}
if (isGrounded && doJump)
{
doJump = false;
rb.AddForce(0, jumpSpeed, 0, ForceMode.VelocityChange);
}
}
IEnumerator Jump()
{
//need the coroutine to make the player jump even if space pressed a bit earlier than
//the character landed
doJump = true;
yield return new WaitForSeconds(0.15f);
doJump = false;
}
private void OnTriggerStay(Collider other)
{
if (other != this.gameObject)
{
isGrounded = true;
}
}
private void OnTriggerExit(Collider other)
{
if (other != this.gameObject)
{
isGrounded = false;
}
}
}
I tried to not use coroutine for jumping but it doesn't help. What helps is deleting the movement line.
I think you are trying to implement "Pre_Update" function, I have found this solution maybe you can use it:
https://answers.unity.com/questions/614343/how-to-implement-preupdate-function.html
I am not sure but I think if you initialize your physics component in the Start function instead of the Awake function then it might work.

Cant Change Friction of Player In Unity2D

I am extremely new to both Unity and C# and have been working on it for a few days. I'm currently trying to stop my player from sliding and to do this I've set the friction value of the players material high so that it doesn't slide. This however creates an issue where my character travels entirely too fast. To get around this I created a child object with a BoxCollider2D tagged as Friction Controller that I can modify. I get a code that changes the friction value of the physics material to 0 when i start moving and 100 when am supposed to stop. The problem is that while this updates the material itself it does not affect the box colliders settings. Does anybody know a solution for this?
using System.Collections.Generic;
using System.Collections.Specialized;
using UnityEngine;
public class Player_Movement : MonoBehaviour
{
GameObject frictionController;
public BoxCollider2D collider;
public float speed = 400f;
public float jumpForce;
private float friction;
private Rigidbody2D rb2d;
private bool isMoving;
// Start is called before the first frame update
void Start()
{
rb2d = GetComponent<Rigidbody2D> ();
}
// Update is called once per frame
void FixedUpdate()
{
float moveHorizontal = Input.GetAxis("Horizontal");
Vector2 movement = new Vector2(moveHorizontal,0);
rb2d.AddForce(movement * speed);
}
void Update()
{
frictionController = GameObject.FindWithTag("Friction Controller");
collider = frictionController.GetComponent<BoxCollider2D>();
if (Input.GetKey("a") || (Input.GetKey("d")))
{
{ Debug.Log("Pressed Button"); }
collider.sharedMaterial.friction = 0;
} else { collider.sharedMaterial.friction = 100; }
///This part isn't complete yet
float moveVertical = Input.GetAxis("Vertical");
Vector2 jump = new Vector2(0, moveVertical);
if (Input.GetKeyDown("space"))
{
rb2d.AddForce(Vector3.up * jumpForce);
}
}
}
I'm not sure that your approach is a particularly good one and is likely to give you problems later on. Since you're using the physics system, a better approach would be to apply a force to your Rigidbody that is the OPPOSITE of its velocity when want it to come to a stop.
Nevertheless here is a solution that effectively does what you want to do using a similar approach to what you're attempting. Rather than manipulating the physics material properties, this solution manipulates the drag value of the rigidbody.
public class Player_Movement : MonoBehaviour
{
private Rigidbody2D rb2d;
private float speed = 100f;
void Start()
{
rb2d = GetComponent<Rigidbody2D> ();
}
void FixedUpdate()
{
float moveHorizontal = Input.GetAxis("Horizontal");
Vector2 movement = new Vector2(moveHorizontal,0);
rb2d.AddForce(movement * speed);
}
void Update()
{
if (Input.GetKey(KeyCode.A) || (Input.GetKey(KeyCode.D)))
{
rb2d.drag = 5; // Adjust this value to modify speed
}
else
{
rb2d.drag = 100; // Adjust this value to modify slippery-ness
}
}
}

I am trying to make an FPS soccer game using Unity, but my script isn't working

So, I am trying to create a soccer game from scratch... all I have done until now, is setting up the ball. This is how I want it to work: When the player collides with the ball, the ball jumps forward a bit. If you start running the ball will be pushed further away.
Now, here is my script for the ball (I am using the standard FPSController as character):
using UnityEngine;
using System.Collections;
public class BallController : MonoBehaviour {
private Rigidbody rb;
public GameObject character;
public float moveSpeed = 1000;
public float shootSpeed = 2000;
bool isTurnedUp = false;
bool isTurnedDown = false;
bool done = false;
// Use this for initialization
void Start () {
rb = GetComponent<Rigidbody>();
}
// Update is called once per frame
void FixedUpdate () {
//Debug.Log(isTurnedUp + ", " + isTurnedDown);
switch (character.GetComponent<UnityStandardAssets.Characters.FirstPerson.FirstPersonController>().m_IsWalking)
{
case true:
if (isTurnedUp == false)
{
moveSpeed = moveSpeed / 1.4f;
isTurnedUp = true;
isTurnedDown = false;
}
break;
case false:
if (isTurnedDown == false)
{
moveSpeed = moveSpeed * 1.4f;
isTurnedDown = true;
isTurnedUp = false;
}
break;
}
}
void Update()
{
if (Input.GetMouseButtonDown(0))
{
if (Vector3.Distance(gameObject.transform.position, character.transform.position) <= 5)
{
float distance = Vector3.Distance(gameObject.transform.position, character.transform.position);
}
}
}
void OnCollisionEnter(Collision collision) {
FixedUpdate();
if (done == false) {
rb.AddForce(Vector3.forward * moveSpeed, ForceMode.Impulse);
done = true;
}
else {
done = false;
}
}
//other
void OnDrawGizmosSelected()
{
Gizmos.color = Color.yellow;
Gizmos.DrawWireSphere(transform.position, 2);
}
}
My problem is that the ball doesn't behave how I want it... it feels like it's about luck if the ball will jump forward when I touch it. Can someone tell me what I did wrong?
Inside of OnCollisionEnter you need to ensure the ball can only be kicked by the player. You can check whether or not the player has collided with the ball by checking the name or tag of the collision. The following example uses the name and assumes your player GameObject is named "Player".
Remove the done flag since this will only allow the player to kick the ball every other time they collide, and remove the FixedUpdate() call since FixedUpdate() is already called automatically every physics calculation.
Finally, if you want to kick the ball away from the player, then you need to calculate the direction away from the collision point instead of using Vector3.forward as seen below.
void OnCollisionEnter(Collision collision)
{
if(collision.gameObject.name == "Player")
{
Vector3 direction = (collision.transform.position - transform.position).normalized;
rb.AddForce(-direction * moveSpeed, ForceMode.Impulse);
}
}

Due to collision checking, my Unity character is occasionally falling through the floor. What can I do to fix this?

I have a basic 2D-oriented Character Controller - custom, that I'm writing for a 2.5D game with 3D models (Therefore I can't use the Unity2D physics and collision volumes).
My controller mostly works, however I'm hitting a strange little issue where every so often - apparently at a certain speed - it skips the collision check and falls through the floor or platform. Can someone spot what I'm doing wrong?
using UnityEngine;
using System.Collections;
public class PlayerController : MonoBehaviour
{
public float PlayerSpeed;
public float JumpPower;
public float _Gravity = 9.89f;
public Vector3 Flip = Vector3.zero;
private Vector3 MoveDirection = Vector3.zero;
private bool FacingLeft = false;
private bool FacingRear = false;
public bool GroundContact = false;
private Rigidbody RigidBody;
private void Awake()
{
RigidBody = GetComponent<Rigidbody>();
}
private void Update()
{
DetectionRays();
MoveDirection.x = PlayerSpeed * Input.GetAxis("Horizontal");
if (GroundContact) {
MoveDirection.y = 0;
if (Input.GetButtonDown("Jump")) {
MoveDirection.y = JumpPower;
}
} else {
MoveDirection.y -= _Gravity * Time.deltaTime;
}
Vector3 movementVector = new Vector3(MoveDirection.x * Time.deltaTime, MoveDirection.y * Time.deltaTime, 0);
transform.Translate(movementVector);
}
private void DetectionRays()
{
DetectDown();
}
private void OnCollisionEnter(Collision Collide)
{
if (Collide.transform.tag == "Ground")
{
GroundContact = true;
}
}
private void DetectDown()
{
RaycastHit Obsticle;
Vector3 RayDownPosit = transform.position;
RayDownPosit.y += 0.8f;
Ray RayDown = new Ray(transform.position, Vector3.down);
Debug.DrawRay(RayDownPosit, Vector3.down, Color.red, 0.05f, false);
GroundContact = false;
if (Physics.Raycast(RayDown, out Obsticle, 0.05f))
{
if (Obsticle.transform.tag == "Ground")
{
GroundContact = true;
}
}
}
}
First, you can attach Box Collider 2D and Rigidbody 2D to 3D models. Try it.
Are you sure you need a custom character controller? CharacterController.Move (or SimpleMove) does collision detection for you.
http://docs.unity3d.com/ScriptReference/CharacterController.Move.html
Alternatively, since you are using Rigidbodies, you should consider using ApplyForce or adding velocity.

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