I want a gameobject spinning around its y-axis. This spinner should have a initial movement direction and when colliding with something, it should change its direction.
I created a little picture to show what I mean, but I want the behaviour for a 3D game.
So I just started with the rotation of the spinner,
public class Spinner : MonoBehaviour
{
[SerializeField]
private float movementSpeed; // speed when moving
[SerializeField]
private float rotationSpeed; // speed when rotating
private Rigidbody rigid;
private Vector3 movementDirection; // the direction the spinner is moving
private void Start()
{
rigid = GetComponent<Rigidbody>();
}
private void FixedUpdate()
{
transform.Rotate(0, rotationSpeed, 0); // rotate the spinner around its y-axis
}
private void OnCollisionEnter(Collision col)
{
// set new direction
}
}
How can I move the spinner, that it moves along a direction and whenever it collides with something, it changes its direction. It should never stop moving or rotating.
I would like to point out a few things:
The Unity Physics Engine will make collisions to absorb part of the force which moves your spinner, so unless you keep adding "artificial" forces to the spinner it will eventually stop.
The "air friction" in your scene will also reduce the force of your
spinner, so it will slow it down. You should add a material to the
spinner which has 0 Dynamic Friction
Based on the comment you left in #reymoss' answer, you may consider
to add the bouncy material to the walls, and not to the spinning
GameObject.
To sum up, the issue here is if you want a GameObject to bounce against a wall using the Physics Engine, the object will eventually stop, because some of the forces will be absorbed in each collision. That means you will need to keep adding external forces every time a collision takes place, to keep it moving endlessly.
Something you can try is,
1- Add a bouncy material to the walls and remove the dynamic friction of your spinner. In the following link you can learn about this:
https://docs.unity3d.com/Manual/class-PhysicMaterial.html
2- Add to the Spinner a Collider, so when it detects a collision with a wall (you can tag the walls as so for example) add an additional force to the spinner in the direction it is already moving, so it will compensate the energy lost during the collision.
void OnTriggerExit(Collider other) {
if(other.tag == "wall") {
rigidbody.AddForce(rigidbody.velocity.normalized * Time.deltaTime * forceAmount);
}
}
The idea is to let the Engine decide the direction of the Spinner after the collision with the wall, and as soon as the GameObject leaves the trigger, you add an additional force in the current direction.
Then you can play with the Bounciness of the wall's material and with the forceAmount, until your spinner moves as you have in mind.
Note: Since you will have 2 materials, one in the walls and another in the spinner, maybe playing with the Friction Combine and Bounce Combine you will be able to avoid the force lost during collisions, so you will not need to add the external force I mention in the second step. However I have never tried this.
Let me know if it works. I can't try myself the solution until I arrive home.
If you give the object an initial velocity, attach a collider, create and assign a Physics Material 2D to the collider (to apply bounciness), and attach Colliders to the walls, you can have it bounce around with minimal code.
private void Start()
{
rigid = GetComponent<Rigidbody>();
rigid.velocity = new Vector3(2f, 3f, 1f) // initialize velocity here
}
Related
I am new to using unity and am having a real problem getting trigger collisions to register.
public void OnTriggerEnter2D(Collider2D other)
{
print("collide");
if (other.CompareTag("Fish"))
{
print("Caught");
}
}
I have 2D polygon colliders and a rigid body on both items. I have also got 1 set a trigger(have tried having both as trigger). However one UI item is a sprite and the other is an image.
Both items are also tagged with "fish"
Would really appreciate any help.
Thanks
There are four things I can think of which need to happen so that OnTriggerEnter gets called:
The two objects' colliders need to actually be overlapping. Just because their rendered pixels are overlapping, doesn't mean their colliders are overlapping. This can be checked in the editor. Their colliders are indicated with a green outline in the Scene tab. If you don't see anything, make sure the button labeled Gizmos is turned on.
The two objects need to be in physics layers which are set to collide with each other. You can check this in Edit > Settings > Physics2D > Layer Collision Matrix.
Both objects need to have Rigidbody2D components attached. Make sure these aren't Rigidbody components, as those are for 3D physics.
The object which contains the OnTriggerEnter2D event needs to have isTrigger = true.
I've tried several things to do.
First I've checked recommendations from another post.
In nutshell:
Checked if I have rigid body at least for one of objects
Checked layers
Checked tags
Played with "is trigger".
Finally, the solution was to add script to object via create and add component button and not to drop written script to it. Have no idea, but for me that was the solution. Even it was same script.
Both a Sprite and an Image can collide with another Image. What might be wrong is that your sprite may look like touching the image however in the scene the canvas might be far away, so camera may deceive you. Here is the sample code for my tests:
Script that moves the Sprite:
private Rigidbody2D _rigidbody;
private void Awake() => _rigidbody = GetComponent<Rigidbody2D>();
private void FixedUpdate()
{
if (Input.GetKey(KeyCode.A))
{
var movement = -transform.right * Time.fixedDeltaTime * 250;
_rigidbody.MovePosition(transform.position + movement);
}
if (Input.GetKey(KeyCode.D))
{
var movement = transform.right * Time.fixedDeltaTime * 250;
_rigidbody.MovePosition(transform.position + movement);
}
}
Trigger script on image:
private void OnTriggerEnter2D(Collider2D other)
{
Debug.Log(other.name);
}
Nothing helps for me, but in my case I didn't know there was a place in code that breaks collision layers (that is do not change the collision matrix settings visually):
Physics2D.IgnoreLayerCollision(...
Check that too and make sure it is not called.
I have a game where map/background is made up of prefabs. My player and prefabs both have rigidbodies and colliders. Neither of them have is trigger checked and the prefabs have collision detection set as continuous dynamic. The player's collision detection is set on continuous. Each of the prefabs have a mesh collider and the individual walls of the prefabs have box colliders (none are set to is trigger). I keep trying to test it on my phone using Unity Remote 5, and every time I move the player it goes through the walls. If anyone has any advice on how to prevent my player from going through the walls, I would really appreciate it!
My movement script is:
public class Movement : MonoBehaviour
{
private Touch touch;
private float speedModifier;
void Start()
{
speedModifier = 0.01f;
}
void Update()
{
if(Input.touchCount > 0)
{
touch = Input.GetTouch(0);
if(touch.phase == TouchPhase.Moved)
{ transform.position = new Vector3(transform.position.x + touch.deltaPosition.x * speedModifier,
transform.position.y,
transform.position.z + touch.deltaPosition.y * speedModifier);
}
}
}
}
It would really help to see your movement script however it sounds like you are moving player by manipulating transform.position or using rigidbody.MovePosition() without setting isKinematic to true. The documentation says;
If the rigidbody has isKinematic set to false, it works like transform.position=newPosition and teleports the object to the new position (rather than performing a smooth transition).
This behaviour will ignore the collision. Also you don't need rigidbody on every GameObject in the scene. 1 rigidbody on the player is enough to collide it with other objects.
depend on what I got from your question, when you are playing and the player hit the wall, it goes inside; so the problem might be the mass of the wall. if you must add a Rigidbody to the wall so you need to add more mass to the wall also edit the border of the box collider and make them reasonably a bit wider, otherwise if you dont need a rigidbody on the wall simply keep just the box collider and it will works good. hope this answer help you, and it will be better if you can explain more the situation using some pics.
Using the Rigidbody position or applying force tends to cause the Rigidbody to clip through other colliders. I recommend changing rigidbody.velocity instead of directly changing the position.
I could really need some help with my GameObjects.
I am working on a game in which I want a pick-up Item to create a Physics Force explosion to blow away the enemies. I made a simple Bomb-Object to test this idea. I added a straightforward code, using a loop to collect all the colliders within its radius, to then addForce to these colliders. Now the code is working properly, but not all my GameObjects are reacting properly.
I looked into why this is, and I noticed that my Collider keeps falling away from the GameObject as soon as I add a RigidBody component to the object. The RigidBody is needed for the AddForce impact. When I remove the rb, the collider stays in place, but the object does not react to the Physics Force.
I added some images to illustrate what I mean:
Image of the Collider of the leaf sinking away..
Example image of objects which DO react to the AddForce.
I already tried to:
Copy/Paste all component settings from the reacting Cube and stone
Gameobjects to the Leaf Gameobject while disabling all other code
such as the c# scripts. The Collider & RB do not fall through the
floor but when Physics Force hits the Collider is blown away while
the GameObject keeps its position.
Try different GameObjects/Collider types.
Removed the water.
Play with amount of force/radius of the bomb.
Edited 'Tag' and 'Layerstyle' of GameObject.
The 'Explosion Code' is added below, however, I don't think the problem is in the code. I added the code to the Main Camera of my scene, and added a simple sphere as the 'bomb' GameObject.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class Explosion : MonoBehaviour
{
public GameObject bomb; //set the position of the explosion
public float power = 10.0f;
public float radius = 10.0f;
public float upForce = 0.0f;
private void FixedUpdate()
{
if (Input.GetKeyDown("space"))
{
print("space key was pressed");
Invoke("Detonate", 1);
}
}
void Detonate()
{
Vector3 explosionPosition = bomb.transform.position; //set the position of our explosion to the position of the bomb.
Collider[] colliders = Physics.OverlapSphere(explosionPosition, radius); //collects all colliders within the radius.
foreach (Collider hit in colliders) { //for each individual collider the following code is ran.
Rigidbody rb = hit.GetComponent<Rigidbody>(); //declare'rb' rigidbody. Get rb component from each collider
if (rb != null)
{
print("BOOM!");
rb.AddExplosionForce(power, explosionPosition, radius, upForce, ForceMode.Impulse); //add force to each collider
}
}
}
}
How do I make the Rigidbody, Collider and GameObject of the leaf hold onto each other like the standard 3D object 'cube', so that I can make these blow away with the Physics Force just like the other models?
Thank you for your time, I have been trying things and looking around on the Internet for hours now but can't seem to find any solution.
What happens if you add the rigidbody in stop mode and press play? Does it move away in a similar manner? This may, and is expected to happen, if your colliders intersect with each other. As soon as you add a rigidbody, they find themselves trapped in a serious collision.
If you don't want to modify the scene, you can fiddle with the collision matrix in project settings / physics
I would like a bullet that is fired from the Enemy, to bounce back off my Players shield.
I have set up my character and the enemy fires towards me at time intervals.
I can then activate my players shield (turning on a BoxCollider) and pressing a button.
So when the Bullet (IsTrigger) collides with my Players Shield (IsNotTrigger) I want to remove this Bullet and then Instantiate a new Bullet from the shield, in the direction of the Enemy.
I am also having an issue destroying the Bullet.
When the OnTriggerEvent or OnColliderEvent occurs (tried both), hundreds of bullets will appear from my Shield. How do I only allow one bullet to be fired towards the enemy?
Below is part of my script, which is located in the GameObject of my Players Shield.
Ideally I would like to destroy the bullet once it has collided with an object.
void OnTriggerEnter(Collider col) {
if (col.tag == "Weapon") {
attack();
}
}
private void attack() {
if (!GameManager.instance.GameOver) {
bulletReturnClone = Instantiate(bulletReturn, transform.position, transform.rotation) as GameObject;
bulletReturnClone.GetComponent<Rigidbody>().velocity = transform.forward * 25f;
Strachan,
That's not how I would approach the problem but I will stick to your desired solution then share some ideas for improvement.
void OnTriggerEnter(Collider col) {
if (col.tag == "Weapon") {
attack(col);
}
}
private void attack(Collider col) {
if (!GameManager.instance.GameOver) {
bulletReturnClone = Instantiate(bulletReturn, transform.position, transform.rotation) as GameObject;
bulletReturnClone.GetComponent<Rigidbody>().velocity = transform.forward * 25f;
// the following line of code should remove the bullet from the shield collider in order to prevent any future problems like spawning multiple bullets or instantly destroying the newly created bullet
bulletReturnClone.GetComponent<Transform>().position *= bulletReturnClone.GetComponent<Rigidbody>().velocity;
Destroy(col.gameObject);
}
}
If your trigger(Bullet) is tagged as weapon this code should achieve your intentional goal of reflecting the bullet in the direction of your shield pointing to by destroying the bullet and instantiating a new one and modifying it's velocity. It works but it's kind of sloppy development. It can be much better if you approach the problem from a different perspective - the one of the Bullet not the Shield.
Let's pretend for a moment you are a Bullet. All you do is fly in the direction you are shot. Once you collide with a terrain you stop/disappear. If this terrain is a shield you don't stop/disappear but change your direction (you get reflected).
So... long story short... the one who should have a trigger collider is the bullet not the shield. OnTriggerEnter(Collider col) for the bullet script will destroy it but if col.tag == "Shield" the bullet will only change its direction without all the useless instantiations and transformations.
I'm too lazy to write the code for the 2nd solution. If you got my point you should be able to easily write it down. Also learning through trials and errors helps you develop (excuse for me being lazy).
Im not really sure why you would want to despawn and respawn the bullet with a new velocity?
Depending on the shield geometry you could look up Coefficients of Restitution and therefore reflect the kinetic energy of the bullet into a realistic velocity.
Note the complexity of that maths will be proportional to the complexity of your shield geometry depending on the different collision primitives.
Sphere-sphere
Sphere-plane
Sphere-terrain (terrain could represent any un-even surface)
Or are you trying to collect the bullets in some sort of "charge" mechanic to release them back at a different time?
I have a Rigidbody attached to my character controller and my enemies. I want the enemies to be able to surround me and have me trapped without me being able to move, so I set the mass property accordingly.
There's just a small problem - if I don't set my mass high enough, the moment the enemies collide with me, my player will go flying into the air. If I don't set my enemies' mass high enough, I will be able to walk right through them. How can I fix this issue? Here is the movement code for the player:
using UnityEngine;
using System.Collections;
public class CharController : MonoBehaviour {
public float speed;
void Start () {
Cursor.lockState = CursorLockMode.Locked;
}
void Update () {
float translation = Input.GetAxis ("Vertical") * speed;
float strafe = Input.GetAxis ("Horizontal") * speed;
translation *= Time.deltaTime;
strafe *= Time.deltaTime;
transform.Translate (strafe, 0, translation);
if (Input.GetKeyDown ("escape")){
Cursor.lockState = CursorLockMode.None;
}
}
}
The problem here is that you're using Transform.Translate() to move your player object. As a result, the player is being moved into clipping with your enemy objects in between physics calculations - so when the next physics calculation comes around, there will be a massive repulsing force to correct this. This is what's sending your player flying.
A better alternative is to use Rigidbody.AddForce() (or one of its variants) to indirectly move your player object. This allows the player object's movement to be taken into account during physics calculations, so it can collide with and be stopped by enemy objects before it starts clipping into them.
If you retrieve and store a reference to the player's Rigidbody in a variable, then you can replace Translate() with something like:
rigidbody.AddRelativeForce(strafe, 0, translation);
Hope this helps! Let me know if you have any questions.
Make sure IsKinematic is checked. UseGravity can be checked or not depend on your situation.
That way, you rigidbody will not be affected by force, collision or joint and is under full control of your script. But maybe they will lose the ability to detect collision as well but I'm not so sure, I haven't tested it yet.
If that was the case, uncheck the IsKinematic and instead, check FreezeRotation and FreezePosition as well. That way, you revoke control of the physics from affecting your position and rotation. You will manually manipulate position & rotation from your script (using CharacterController).
References:
https://docs.unity3d.com/ScriptReference/Rigidbody-isKinematic.html
https://docs.unity3d.com/Manual/class-Rigidbody.html