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Unity collision with ground doesnt work (noob)

So I just started working with unity and wanted that my player can only jump when he's touching the ground. I gave a "Ground" tag to my ground and checked, If the player is touching the gameObject with the "Ground" tag, so the grounded bool would be set to true. Somehow my collision doesnt work.
public class PlayerMovement : MonoBehaviour
{
[SerializeField] float speed = 10;
private Rigidbody2D body;
private Animator animate;
private bool grounded;
private void Awake()
{
body = GetComponent<Rigidbody2D>();
animate = GetComponent<Animator>();
}
private void Update()
{
float horizontalInput = Input.GetAxis("Horizontal");
body.velocity = new Vector2(horizontalInput * speed, body.velocity.y);
if (horizontalInput > 0.01f)
transform.localScale = new Vector3(7, 7, 7);
else if (horizontalInput < -0.01f)
transform.localScale = new Vector3(-7, 7, 7);
if (Input.GetKeyDown(KeyCode.Space) && grounded == true)
Jump();
animate.SetBool("Run", horizontalInput != 0);
animate.SetBool("grounded", grounded);
}
private void Jump()
{
body.velocity = new Vector2(body.velocity.x, speed);
animate.SetTrigger("Jump");
grounded = false;
}
private void OncollisionEnter2D(Collision2D collision)
{
Debug.Log("Collision detected");
if (collision.gameObject.tag == "Ground")
grounded = true;
Debug.Log("ground is being touched");
}
}
I thought it would be a good idea to let certain steps of this process output a log message, but my log stayed empty after testing.

OnCollisionEnter2D would be the right spelling of what you intented to write. So, change OncollisionEnter2D to OnCollisionEnter2D, because capitalization matters.
As we're already here and it won't harm, I'd also suggest you to use CompareTag instead of tag == string as it performs slightly better due to less memory allocation (as you can read here: https://learn.unity.com/tutorial/fixing-performance-problems#5c7f8528edbc2a002053b595), so it's a good habit to get used to CompareTag:
if(collision.gameObject.CompareTag("MyTag"))
To finish up this answer, I'd like to point out that you might want to consider fixing your auto-completion suggestions (in Visual Studio and Visual Studio Code: IntelliSense) in case it doesn't work. With the help of this tool, you'll never misspell something like this again, because the correct name will be suggested as soon as you start writing.

Checking if RigidBody is grounded?

I have a GameObject with a Rigidbody, Mesh Collider, Skinned Mesh Renderer, and the below script.
I'm trying to check if it is Grounded, but the Console continuously spits out "Not Grounded!" when it is, so obviously something is wrong here. Can anyone please help?
public class GroundCheck : MonoBehaviour
{
public float Height;
bool IsGrounded;
Ray ray;
MeshRenderer renda;
private void Start()
{
Height = renda.bounds.size.y;
}
void Update()
{
if (Physics.Raycast(transform.position, Vector3.down, Height))
{
IsGrounded = true;
Debug.Log("Grounded");
}
else
{
IsGrounded = false;
Debug.Log("Not Grounded!");
}
}
}

Another option for checking if the rigidBody is grounded is using the OnTriggerStay function.
void OnTriggerStay(Collider other)
{
if (other.Transform.Tag == "Ground")
{
IsGrounded = true;
Debug.Log("Grounded");
}
else
{
IsGrounded = false;
Debug.Log("Not Grounded!");
}
}

I've checked your code with a simple scene with a plane and a cube, and it works.
It only spawns NotGrounded when it's clearly "floating" arround or the object has the half of it's body outside the plane.
Check those things drawing the Ray, this should give your more information about what is going wrong with your mesh.
Also if the problem is how the game is perceiving the Height of your Skinned Mesh you can also use SkinnedMeshRenderer.localBounds who returns the AABB of the object.

There is a better way to check if your rigidbody is grounded than collision checking and rays. But first, why is collision checking not a good idea: If your level is a single model the walls will too be tagged with the "Ground" tag and hitting a wall will return true, which you don't want. Rays can be used, but that's too much math you don't need to waste time with.
Instead of using new objects and methods, just check if the position is changing:
private float lastYposition;
private bool grounded;
void Start() {
lastYposition = transform.position.y;
}
void Update() {
grounded = (lastYposition == transform.position.y); // Checks if Y has changed since last frame
lastYposition = transform.position.y;
}
From here it's up to you what logic you are going to add.

Get the closest contact point to the bottom. Check if the contact normal is within range.
void OnCollisionStay(Collision collision)
{
var bottom = renderer.bounds.center;
bottom.y -= renderer.bounds.extents.y;
float minDist = float.PositiveInfinity;
float angle = 180f;
// Find closest point to bottom.
for (int i = 0; i < collision.contactCount; i++)
{
var contact = collision.GetContact(i);
var tempDist = Vector3.Distance(contact.point, bottom);
if(tempDist < minDist)
{
minDist = tempDist;
// Check how close the contact normal is to our up vector.
angle = Vector3.Angle(transform.up, contact.normal);
}
}
// Check if the angle is too steep.
if (angle <= 45f) IsGrounded = true;
else IsGrounded = false;
}
void OnCollisionExit(Collision collision)
{
IsGrounded = false;
}
I came up with this answer after reading amitklein's answer.

private void Jump()
{
if (Input.GetKeyDown(KeyCode.Space))
{
if (transform.position.y == 0f)
{
rb.AddRelativeForce(Vector3.up * jumpForce);
}
}
}
I used this approach to jump using addrelativeforce of rigid body only when the position of y in 0.

Unity Rigidbody is sliding after jumping

I would like my character to jump diagonally but when it hits the ground it slides.
private void Update()
{
if (Input.GetMouseButtonUp(0) && isGrounded())
{
//jump
timeHeld = 0;
Debug.Log("MouseButtonUp = true");
rb.AddForce(jumpDirection, ForceMode2D.Impulse);
}
else if (isGrounded())
{
rb.velocity = Vector2.zero;
}
}
this code somehow works but it glitches when the player hits the ground. I need to put some amount of force to get him out of isGrounded() or he will just get some pixels up and be instantly pushed down again.
This is my isGrounded() function
private bool isGrounded()
{
RaycastHit2D raycastHit = Physics2D.BoxCast(boxCollider2d.bounds.center, boxCollider2d.bounds.size, 0f, Vector2.down, 0.1f, platformLayerMask);
return raycastHit.collider != null;
}
the problem is obviously my distance which is 0.1f in Boxcast(). Any ideas how to fix that?

No need to check the ground by yourself.
Add a unity event called OnCollisionEnter
Inside, check if the collider is the ground
If true, then velocity = zero

Why isn't my 2D bullet's collider colliding with anything?

I'm trying to make a platformer game that uses 2D sprites in 3D space. For some reason, though the bullet the player shoots fires correctly from the GO that's a child of the player, it won't collide with anything (enemies, other objects, etc.) in either 2D or 3D. I have a 3D character controller on the parent player GO, but that doesn't affect the bullet object I'm firing, does it?
Colliders on everything appropriately.
Tried with IsTrigger both on and off in various combinations.
Objects are on the same layer and the same Z axis position.
//BULLET FIRING SCRIPT
void Update()
{
if (Input.GetButtonDown("Fire2") && !Input.GetButton("Fire3") &&
Time.time > nextFireTime)
{
Rigidbody2D cloneRb = Instantiate(bullet,
bulletSpawn.position, Quaternion.identity) as Rigidbody2D;
cloneRb.AddForce(bulletPrefab.transform.right *
projectileForce);
nextFireTime = Time.time + fireRate;
}
}
//____________________________________________________________
//BULLET OBJECT SCRIPT
private void Start()
{
direction = Input.GetAxisRaw("Horizontal");
if (direction == -1)
{
facingLeft = true;
}
else if (direction == 1)
{
facingLeft = false;
}
else if (direction == 0)
{
facingLeft = false;
}
if (facingLeft == false)
{
rb.velocity = transform.right * speed;
Debug.Log("Fired Bullet");
}
else
{
bulletPrefab.transform.Rotate(0, 180, 0);
firePoint.transform.Rotate(0, 180, 0);
Debug.Log("Rotated Bullet");
Debug.Log("Fired Bullet Left");
rb.velocity = transform.right * speed;
}
}
// Update is called once per frame
void Update()
{
}
public void OnTriggerEnter2D(Collider2D collider)
{
Debug.Log("Bullet Hit:");
Debug.Log(collider.name);
Enemy enemy = collider.GetComponent<Enemy>();
if (enemy != null)
{
enemy.TakeDamage(damage);
}
Destroy(gameObject);
}
Expected Result: Bullet object collides with other objects, prints Debug.Log output and gets destroyed.
Actual Result: Bullet object fires through, in front of, or behind other objects that also have colliders and there is no Debug.Log output. Bullet does not get destroyed and so instantiates clones infinitely when assigned input is entered.

Fixed issue by checking Default/Default in the Layer Collision Matrix under Edit-->Project Settings-->Physics. Not sure if it's supposed to be checked by default and somehow got unchecked but checking it solved the problem.

Prevent moving in raycast direction when raycast hits something

I'm working on a third person controller and I'm trying to prevent movement when a raycast in front of the player hits something. Currently when the player collides with a block the blend tree is set to 0 so that it shows the Idle animation. In this case the player appears to be not moving, which it obviously isn't because it's colliding with something, but the input of the user is still there.
This is visible when the player presses the jump button, because the player moves in the direction the user was initially trying to move. In the player controller there is a part that prevents the user from moving after the jump button has been pressed during the length of the jump (Until the player is grounded again). What I'm trying to achieve is that when the user is moving against something and presses the jump button the player will just jump up and won't go in the direction the user was initially trying to go, even if there is no more collider or obstruction.
Something like if the raycast hits something the user won't be able to add movement in that direction, but is still able to turn the player away from the object and move in that direction as long as the raycast doesn't hit a collider.
I'm no c# wizard, so most of the code below comes from a tutorial. I can write a raycast myself, but have no clue how to write the rest of what I'm trying to achieve.
Edit: Current script
public RaycastHit _Hit;
public LayerMask _RaycastCollidableLayers; //Set this in inspector, makes you able to say which layers should be collided with and which not.
public float _CheckDistance = 5f;
void Update()
{
PushStates();
// Input
Vector2 input = new Vector2(Input.GetAxisRaw("Horizontal"), Input.GetAxisRaw("Vertical"));
Vector2 inputDir = input.normalized;
bool running = Input.GetButton("Run");
if (IsNotBlocked())
{
Move(inputDir, running);
}
float animationSpeedPercent = ((running) ? currentSpeed / runSpeed : currentSpeed / walkSpeed * .5f);
anim.SetFloat("speedPercent", animationSpeedPercent, speedSmoothTime, Time.deltaTime);
anim.SetFloat("speedPercentPush", animationSpeedPercent, speedSmoothTime, Time.deltaTime);
// Check if walking or running
if (animationSpeedPercent < 0.51f)
{
if (ShortJumpRaycast())
{
if (Input.GetButtonDown("Jump") && Time.time > canJump)
{
ShortJump();
}
}
else
{
if (Input.GetButtonDown("Jump") && Time.time > canJump)
{
JumpWalk();
}
}
}
else
{
//Debug.Log("You are Running");
if (Input.GetButtonDown("Jump") && Time.time > canJump)
{
JumpRun();
}
}
JumpCheck();
}
void Move(Vector2 inputDir, bool running)
{
if (inputDir != Vector2.zero)
{
float targetRotation = Mathf.Atan2(inputDir.x, inputDir.y) * Mathf.Rad2Deg + cameraT.eulerAngles.y;
transform.eulerAngles = Vector3.up * Mathf.SmoothDampAngle(transform.eulerAngles.y, targetRotation, ref turnSmoothVelocity, GetModifiedSmoothTime(turnSmoothTime));
}
float targetSpeed = ((running) ? runSpeed : walkSpeed) * inputDir.magnitude;
currentSpeed = Mathf.SmoothDamp(currentSpeed, targetSpeed, ref speedSmoothVelocity, GetModifiedSmoothTime(speedSmoothTime));
velocityY += Time.deltaTime * gravity;
Vector3 velocity = transform.forward * currentSpeed + Vector3.up * velocityY;
controller.Move(velocity * Time.deltaTime);
currentSpeed = new Vector2(controller.velocity.x, controller.velocity.z).magnitude;
// Checks if player is not grounded and is falling
if (GroundCheck())
{
velocityY = 0;
anim.SetBool("onAir", false);
}
else
{
anim.SetBool("onAir", true);
}
}
bool IsNotBlocked()
{
Vector3 forward = transform.TransformDirection(Vector3.forward);
if (Physics.Raycast(transform.position, forward, out _Hit, _CheckDistance + 0.1f, _RaycastCollidableLayers))
if (_Hit.collider == null)
{
Debug.Log("Raycast hit nothing");
return true;
}
GameObject go = _Hit.collider.gameObject;
if (go == null) //If no object hit, nothing is blocked.
return true;
else //An object was hit.
return false;
}

Directly before move you can raycast in the direction of the movement and if it hits something you can cancel movement.
Something like:
Vector3 velocity = transform.forward * currentSpeed + Vector3.up * velocityY;
if(!Physics.Raycast(transform.position, transform.forward, distance)
{
controller.Move(velocity * Time.deltaTime);
}
else
{
controller.Move(Vector3.up * velocityY * Time.deltaTime);
}

Something like if the raycast hits something the user won't be able to add movement in that direction
Here is an example of how you can perform a raycast to check whether something was hit or not.
//Example raycast code
//Variables
public RayCastHit _Hit;
public LayerMask _RaycastCollidableLayers; //Set this in inspector, makes you able to say which layers should be collided with and which not.
public float _CheckDistance = 5f;
//Method
bool IsNotBlocked(){
Vector3 forward = transform.TransformDirection(Vector3.forward);
if (Physics.Raycast(transform.position, forward, out _Hit, _CheckDistance + 0.1f, _RaycastCollidableLayers))
if (_Hit.collider == null)
{
Debug.Log("Raycast hit nothing");
return true;
}
GameObject go = _Hit.collider.gameObject;
if (go == null) //If no object hit, nothing is blocked.
return true;
else //An object was hit.
return false;
}
Basically,
The length of the ray is CheckDistance.
RayCastCollidableLayers determines which layers an object can be in for it to be collidable with the ray we create.
The code sets a direction stored in "forward", a raycast is then performed from the transform.position (position of object this script is attached to) in direction Vector3.Forward.
_Hit saves whatever the raycast hits. An object can then be accessed through it and stored as a GameObject. I call this object 'go'.
Feel free to ask questions.