I am making a script to be used on the Main Camera object of Unity3D so the camera follows the character in a 2D platformer world.
I tried to translate this from a UnityScript script to c#, I am getting an error in line 26: "Cannot modify a value type return value of 'UnityEngine.Transform.position'. Consider storing the value in a temporary variable."
Original UnityScript Version
var cameraTarget : GameObject;
var player : GameObject;
var smoothTime : float = 0,1;
var cameraFollowX : boolean = true;
var cameraFollowY : boolean = true;
var cameraFollowHeight : boolean = false;
var cameraHeight : float = 2.5;
var velocity : Vector2;
private var thisTransform : Transform;
function Start ()
{
thisTransform = transform;
}
function Update ()
{
if (cameraFollowX)
{
thisTransform.position.x = Mathf.SmoothDamp (thisTransform.position.x, cameraTarget.transform.position.x, velocity.x, smoothTime);
}
if (cameraFollowY)
{
thisTransform.position.y = Mathf.SmoothDamp (thisTransform.position.y, cameraTarget.transform.position.y, velocity.y, smoothTime);
}
if (!cameraFollowX & cameraFollowHeight)
{
camera.transform.position.y = cameraHeight;
}
}
My C# Version
using UnityEngine;
using System.Collections;
public class CameraSmoothFollow : MonoBehaviour {
public GameObject cameraTarget; // object to look at or follow
public GameObject player; // player object for moving
public float smoothTime = 0.1f; // time for dampen
public bool cameraFollowX = true; // camera follows on horizontal
public bool cameraFollowY = true; // camera follows on vertical
public bool cameraFollowHeight = true; // camera follow CameraTarget object height
public float cameraHeight = 2.5f; // height of camera adjustable
public Vector2 velocity; // speed of camera movement
private Transform thisTransform; // camera Transform
// Use this for initialization
void Start () {
thisTransform = transform;
}
// Update is called once per frame
void Update () {
if (cameraFollowX){
thisTransform.position.x = Mathf.SmoothDamp (thisTransform.position.x, cameraTarget.transform.position.x, ref velocity.x, smoothTime); // Here i get the error
}
if (cameraFollowY) {
// to do
}
if (!cameraFollowX & cameraFollowHeight) {
// to do
}
}
}
Any help will be appreciated.
This error occurs because Transform.position is of a value type (probably a struct). This means that when you access the X property of position, you are accessing a COPY and NOT the real thing. To assign to the position property, you will need to create a new Vector3 and assign it to the position property. Your code will look something like this:
thisTransform.position = new Vector3 (Mathf.SmoothDamp (thisTransform.position.x, cameraTarget.transform.position.x, ref velocity.x, smoothTime), thisTransform.position.y, thisTransform.position.z);
or perhaps more cleaner:
float tempX = new Vector3 (Mathf.SmoothDamp (thisTransform.position.x, cameraTarget.transform.position.x, ref velocity.x, smoothTime);
thisTransform.position = new Vector3 (tempX, thisTransform.position.y, thisTransform.position.z);
You can also use this smooth follow script for both 2d and 3d camera and its very simple.
using UnityEngine;
using System.Collections;
public class FollowCamera : MonoBehaviour {
public float interpVelocity;
public float minDistance;
public float followDistance;
public GameObject target;
public Vector3 offset;
Vector3 targetPos;
// Use this for initialization
void Start () {
targetPos = transform.position;
}
// Update is called once per frame
void FixedUpdate () {
if (target)
{
Vector3 posNoZ = transform.position;
posNoZ.z = target.transform.position.z;
Vector3 targetDirection = (target.transform.position - posNoZ);
interpVelocity = targetDirection.magnitude * 5f;
targetPos = transform.position + (targetDirection.normalized * interpVelocity * Time.deltaTime);
transform.position = Vector3.Lerp( transform.position, targetPos + offset, 0.25f);
}
}
}
got it from github here
https://gist.github.com/unity3diy/5aa0b098cb06b3ccbe47
Use FixedUpdate()
If it's Update() the camera jerking will occur.
Related
Hello everyone and thanks in advance for your answers!
I am a beginner in unity, coding my second game after i finshed a couple of tutorials.
Since today, i noticed that suddenly all my "GameObjects" have a "UnityEngine." in front of them.
I have no idea how that happened, and it is also not just in one script, but all of them. Heres an example of it:
UnityEngine.GameObject item = (UnityEngine.GameObject)Instantiate(itemGOList[i], spawnTransform, spawnRotation);
This worked fine before without the "UnityEngine.", but now it only works when its written this way.
Do you know how this could have happened and how to revert it?
This is one of the scripts:
using UnityEngine;
using UnityEngine.EventSystems;
public class Turret : MonoBehaviour
{
private Transform target;
private Enemy targetEnemy;
[Header("General")]
public float range = 10f;
[Header("Use Bullets/missiles (default)")]
public UnityEngine.GameObject bulletPrefab;
public float fireRate = 1f;
private float fireCountdown = 0f;
public AudioClip shootingSound;
private AudioSource audioSource;
[Header("Use Laser (default)")]
public bool useLaser = false;
public int damageOverTime = 20;
public float slowAmount = .5f;
public LineRenderer lineRenderer;
public ParticleSystem impactEffect;
public Light impactLight;
[Header("Unity Setup Fields")]
public string enemyTag = "Enemy";
public Transform partToRotate;
public float turnSpeed = 10f;
public Transform firePoint;
void Start()
{
InvokeRepeating(nameof(UpdateTarget), 0f, 0.3f); // Call the UpdateTarget Method after 0 seconds, then repeat every 0.3 seconds.
audioSource = GetComponent<AudioSource>(); //Puts the AudioSource of this GO (the turret) into the variable audioSource.
}
void UpdateTarget ()
{
UnityEngine.GameObject[] enemies = UnityEngine.GameObject.FindGameObjectsWithTag(enemyTag); // Find all enemies (and store in a list?).
float shortestDistance = Mathf.Infinity; // Create a float for the shortest distance to an enemy.
UnityEngine.GameObject nearestEnemy = null; // Create a variable which stores the nearest enemy as a gameobject.
foreach (UnityEngine.GameObject enemy in enemies) // Loop through the enemies array.
{
float distanceToEnemy = Vector3.Distance(transform.position, enemy.transform.position); //Get the distance to each enemy and stores it.
if (distanceToEnemy < shortestDistance) // If any of the enemies is closer than the original, make this distance the new shortestDistance and the new enemy to the nearestEnemy.
{
shortestDistance = distanceToEnemy;
nearestEnemy = enemy;
}
}
if (nearestEnemy != null && shortestDistance <= range) // Sets the target to the nearestEnemy (only if its in range and not null).
{
target = nearestEnemy.transform;
targetEnemy = nearestEnemy.GetComponent<Enemy>();
}
else
{
target = null;
}
}
void Update()
{
if (target == null) // If there is no target, do nothing.
{
if (useLaser)
{
if (lineRenderer.enabled)
{
lineRenderer.enabled = false;
impactEffect.Stop();
impactLight.enabled = false;
audioSource.Stop();
}
}
return;
}
LockOnTarget();
if (useLaser)
{
Laser();
}
else
{
if (fireCountdown <= 0f)
{
Shoot();
fireCountdown = 1f / fireRate;
}
fireCountdown -= Time.deltaTime;
}
}
void Laser()
{
targetEnemy.TakeDamage(damageOverTime * Time.deltaTime);
targetEnemy.Slow(slowAmount);
if (!lineRenderer.enabled)
{
lineRenderer.enabled = true;
impactEffect.Play();
impactLight.enabled = true;
if (audioSource.isPlaying == false)
{
audioSource.Play();
}
}
lineRenderer.SetPosition(0, firePoint.position);
lineRenderer.SetPosition(1, target.position);
Vector3 dir = firePoint.position - target.position;
impactEffect.transform.position = target.position + dir.normalized * 1f;
impactEffect.transform.rotation = Quaternion.LookRotation(dir);
}
void LockOnTarget()
{
Vector3 dir = target.position - transform.position; // Store the direction from turret to target.
Quaternion lookRotation = Quaternion.LookRotation(dir); // I have no idea how this works...
Vector3 rotation = Quaternion.Lerp(partToRotate.rotation, lookRotation, Time.deltaTime * turnSpeed).eulerAngles; // Convert quaternion angles to euler angles and Lerp it (smoothing out the transition).
partToRotate.rotation = Quaternion.Euler(0f, rotation.y, 0f); // Only rotate around the y-axis.
}
void Shoot()
{
UnityEngine.GameObject bulletGO = (UnityEngine.GameObject)Instantiate(bulletPrefab, firePoint.position, firePoint.rotation); // Spawn a bullet at the location and rotation of firePoint. (Also makes this a GO to reference it.
Bullet bullet = bulletGO.GetComponent<Bullet>(); // I have no idea how this works...
audioSource.PlayOneShot(shootingSound, 0.2f);
if (bullet != null) // If there is a bullet, use the seek method from the bullet script.
{
bullet.Seek(target);
}
}
void OnDrawGizmosSelected() // Do this method if gizmo is selected.
{
Gizmos.color = Color.red;
Gizmos.DrawWireSphere(transform.position, range); // Draw a wire sphere on the selected point (selected turret f. e.) and give it the towers range.
}
}
The problem was that i had a script called "GameObject" in my Unity Project.
I was also able to rename all "UnityEngine.GameObject" to "Gameobject" by using the Quick Action in Visual Studio.
Should I use Cinemachine for that or it's better to do it with a script from scratch ?
The script is attached to the Main Camera.
Now it's orbit only left right. I want it to orbit 360 degrees with clamp so it wont move down to the floor and to up back.
I should also the Y and not only the X but not sure how.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerFollow : MonoBehaviour {
public Transform PlayerTransform;
private Vector3 _cameraOffset;
[Range(0.01f, 1.0f)]
public float SmoothFactor = 0.5f;
public bool LookAtPlayer = false;
public bool RotateAroundPlayer = true;
public float RotationsSpeed = 5.0f;
// Use this for initialization
void Start () {
_cameraOffset = transform.position - PlayerTransform.position;
}
// LateUpdate is called after Update methods
void LateUpdate () {
if(RotateAroundPlayer)
{
Quaternion camTurnAngle =
Quaternion.AngleAxis(Input.GetAxis("Mouse X") * RotationsSpeed, Vector3.up);
_cameraOffset = camTurnAngle * _cameraOffset;
}
Vector3 newPos = PlayerTransform.position + _cameraOffset;
transform.position = Vector3.Slerp(transform.position, newPos, SmoothFactor);
if (LookAtPlayer || RotateAroundPlayer)
transform.LookAt(PlayerTransform);
}
}
I have a capsule and a sphere connected by a Configurable Joint. I move the player using the capsule rigidbody and the sphere acts as a caster wheel(like a unicycle with suspension).
As the sphere is a child of the capsule, I am using GetComponentInChildren to try and access the Configurable Joint's, Y Drive's, Position Spring (float value).
I got lost trying to google this problem.
Here is the relevant code, everything in //Comment does not work:
public class PlayerMovement : MonoBehaviour
{
private Rigidbody rb;
public float moveSpeed = 10f;
public float distanceGround;
public bool isGrounded = false;
public bool isCrouch = false;
void Awake()
{
rb = GetComponent<Rigidbody>();
}
void Start()
{
distanceGround = GetComponent<Collider>().bounds.extents.y;
}
void FixedUpdate()
{
Movement();
}
private void Movement()
{
float inputX = Input.GetAxis("LStickHorz");
float InputZ = -Input.GetAxis("LStickVert");
float multiplier = 1f;
if (!Physics.Raycast (transform.position, -Vector3.up, distanceGround + 1.5f))
{
isGrounded = false;
print("IN AIR.....");
}
else
{
isGrounded = true;
print("....onGround");
//Debug.DrawRay(?,?, Color.red, 1.25f);
}
if (Physics.Raycast (transform.position, -Vector3.up, distanceGround + .2f))
{
isCrouch = true;
print("VVVVVVVVVVVVVV");
//ConfigurableJoint cj = gameObject.GetComponentInChildren(typeof(ConfigurableJoint)) as ConfigurableJoint;
//set y spring value
//cj.yDrive.positionSpring = 50f;
}
else
{
isCrouch = false;
}
if (!isGrounded)
{
multiplier = .2f;
}
if (isCrouch)
{
multiplier = .2f;
}
Vector3 moveVector = new Vector3(inputX * multiplier, 0.0f, InputZ * multiplier);
//if ()
rb.AddForce(moveVector * moveSpeed);
}
}
Let's start with your first comment, the function Debug.DrawRay(). If you look at the documentation here it will tell you all parameters of the function and show you an example. For this function, the first two parameters are position and direction:
Debug.DrawRay(transform.position, Vector3.up * 5, Color.red, 1.25f)
The second issue is you cannot set the positionSpring field directly. You will need to store a reference to the yDrive in another variable, change the value of positionSpring, then set yDrive to the temp variable:
// Get the COnfigurableJoint component
ConfigurableJoint cj = gameObject.GetComponent<ConfigurableJoint>();
// Grab a reference to the JointDrive
JointDrive jd = cj.yDrive;
// Set the value of positionSpring here
jd.positionSpring = 50.0f;
// Apply the changes you made to the yDrive back to the ConfigurableJoint
cj.yDrive = jd;
I am messing around in Unity and wanted to make a mechanic where a box would touch another object and then that object would follow the Player.
I have Cube set up like this:
And a Sphere with a Box Collider with same options.
My Player script is thus:
public class Player : MonoBehaviour {
public float speed = 0.0f;
public float moveX = 0.0f;
public float moveY = 0.0f;
public GameObject player;
public GameObject obj;
//public float force = 0.0f;
private bool collided = false;
// Use this for initialization
void Start () {
player = GameObject.FindWithTag ("Player");
}
// Update is called once per frame
void FixedUpdate () {
moveX = Input.GetAxis ("Horizontal");
moveY = Input.GetAxis ("Vertical");
player.GetComponent<Rigidbody> ().velocity = new Vector2 (moveX * speed, moveY * speed);
}
void OnCollisionEnter (Collision col) {
if (col.gameObject == obj) {
collided = true;
}
}
void OnCollisionExit (Collision col) {
if (col.gameObject == obj) {
collided = false;
}
}
void Update () {
if(collided) {
obj.transform.position = (player.transform.position - obj.transform.position)*speed;
}
}
}
What have I yet to do? Hoping someone can nudge me in the right direction.
I will provide you two scripts.
1st Script is FollowTarget. This will follow your target forcely.
2nd Script is SmoothFollow which will follow your target in a smooth movement.
FollowTarget.cs
using System;
using UnityEngine;
public class FollowTarget : MonoBehaviour
{
public Transform target;
public Vector3 offset = new Vector3(0f, 7.5f, 0f);
private void LateUpdate()
{
transform.position = target.position + offset;
}
}
SmoothFollow.cs
using UnityEngine;
public class SmoothFollow : MonoBehaviour
{
// The target we are following
[SerializeField]
private Transform target;
// The distance in the x-z plane to the target
[SerializeField]
private float distance = 10.0f;
// the height we want the camera to be above the target
[SerializeField]
private float height = 5.0f;
[SerializeField]
private float rotationDamping;
[SerializeField]
private float heightDamping;
// Use this for initialization
void Start() { }
// Update is called once per frame
void LateUpdate()
{
// Early out if we don't have a target
if (!target)
return;
// Calculate the current rotation angles
var wantedRotationAngle = target.eulerAngles.y;
var wantedHeight = target.position.y + height;
var currentRotationAngle = transform.eulerAngles.y;
var currentHeight = transform.position.y;
// Damp the rotation around the y-axis
currentRotationAngle = Mathf.LerpAngle(currentRotationAngle, wantedRotationAngle, rotationDamping * Time.deltaTime);
// Damp the height
currentHeight = Mathf.Lerp(currentHeight, wantedHeight, heightDamping * Time.deltaTime);
// Convert the angle into a rotation
var currentRotation = Quaternion.Euler(0, currentRotationAngle, 0);
// Set the position of the camera on the x-z plane to:
// distance meters behind the target
transform.position = target.position;
transform.position -= currentRotation * Vector3.forward * distance;
// Set the height of the camera
transform.position = new Vector3(transform.position.x ,currentHeight , transform.position.z);
// Always look at the target
transform.LookAt(target);
}
}
Just choose one of them and then attach it to the gameObject. Like another box that is suppose to follow.
Remove your Update() function in your script as you don't need it anymore.
Also Remove your OnCollisionExit()
void OnCollisionEnter (Collision col) {
if (col.gameObject == obj) {
// If you choose to use SmoothFollow Uncomment this.
//col.GetComponent<SmoothFollow>().target = this.transform;
// If you choose to use FollowTarget Uncomment this
//col.GetComponent<FollowTarget>().target = this.transform;
}
}
I have an object called Ball, and I added keyboard interactivity to it(WASD to move the ball)
I need the camera to stay behind and follow the ball, but I am getting errors.
using UnityEngine;
using System.Collections;
public class ballmain : MonoBehaviour {
public bool isMoving = false;
public string direction;
public float camX;
public float camY;
public float camZ;
// Use this for initialization
void Start () {
Debug.Log("Can this run!!!");
}
// Update is called once per frame
void Update () {
camX = rigidbody.transform.position.x -=10;
camY = rigidbody.transform.position.y -=10;
camZ = rigidbody.transform.position.z;
camera.transform.position = new Vector3(camX, camY, camZ);
//followed by code that makes ball move
}
}
I get error "Assets/ballmain.cs(18,44): error CS1612: Cannot modify a value type return value of 'UnityEngine.Transform.position'. Consider storing the value in a temporary variable"
Does anyone know the answer? If I comment out the code about the camera the ball can move around.
here you go . a full code.
Simple Following
using UnityEngine;
using System.Collections;
public class Follow: MonoBehaviour {
public Transform target;
public float smooth= 5.0f;
void Update (){
transform.position = Vector3.Lerp (
transform.position, target.position,
Time.deltaTime * smooth);
}
}
Advanced Following
using UnityEngine;
using System.Collections;
public class SmoothFollowScript: MonoBehaviour {
// The target we are following
public Transform target;
// The distance in the x-z plane to the target
public int distance = 10.0;
// the height we want the camera to be above the target
public int height = 10.0;
// How much we
public heightDamping = 2.0;
public rotationDamping = 0.6;
void LateUpdate (){
// Early out if we don't have a target
if (TargetScript.russ == true){
if (!target)
return;
// Calculate the current rotation angles
wantedRotationAngle = target.eulerAngles.y;
wantedHeight = target.position.y + height;
currentRotationAngle = transform.eulerAngles.y;
currentHeight = transform.position.y;
// Damp the rotation around the y-axis
currentRotationAngle = Mathf.LerpAngle (currentRotationAngle, wantedRotationAngle, rotationDamping * Time.deltaTime);
// Damp the height
currentHeight = Mathf.Lerp (currentHeight, wantedHeight, heightDamping * Time.deltaTime);
// Convert the angle into a rotation
currentRotation = Quaternion.Euler (0, currentRotationAngle, 0);
// Set the position of the camera on the x-z plane to:
// distance meters behind the target
transform.position = target.position;
transform.position -= currentRotation * Vector3.forward * distance;
// Set the height of the camera
transform.position.y = currentHeight;
// Always look at the target
transform.LookAt (target);
}
}
}
If you just simply want to follow the target object align the position of the camera the way you want it and make the camera the child of the target object and the rest will do
Here're one script I found useful during my game development. I didn't create them so I give credit to wiki.unity3d.com for providing this amazing script.
Smooth Follow:
using UnityEngine;
using System.Collections;
public class SmoothFollow2 : MonoBehaviour {
public Transform target;
public float distance = 3.0f;
public float height = 3.0f;
public float damping = 5.0f;
public bool smoothRotation = true;
public bool followBehind = true;
public float rotationDamping = 10.0f;
void Update () {
Vector3 wantedPosition;
if(followBehind)
wantedPosition = target.TransformPoint(0, height, -distance);
else
wantedPosition = target.TransformPoint(0, height, distance);
transform.position = Vector3.Lerp (transform.position, wantedPosition, Time.deltaTime * damping);
if (smoothRotation) {
Quaternion wantedRotation = Quaternion.LookRotation(target.position - transform.position, target.up);
transform.rotation = Quaternion.Slerp (transform.rotation, wantedRotation, Time.deltaTime * rotationDamping);
}
else transform.LookAt (target, target.up);
}
}
More information about my work
Include Standard Mobile Asset to your project. It contains a SmoothFollow2D.js code in its script section. Attach this code with the gameobject and initialize public variables. This will simply do the job for you.
I found this simple and useful unity 2d camera follow script.
using UnityEngine;
using System.Collections;
public class FollowCamera : MonoBehaviour {
public float interpVelocity;
public float minDistance;
public float followDistance;
public GameObject target;
public Vector3 offset;
Vector3 targetPos;
// Use this for initialization
void Start () {
targetPos = transform.position;
}
// Update is called once per frame
void FixedUpdate () {
if (target)
{
Vector3 posNoZ = transform.position;
posNoZ.z = target.transform.position.z;
Vector3 targetDirection = (target.transform.position - posNoZ);
interpVelocity = targetDirection.magnitude * 5f;
targetPos = transform.position + (targetDirection.normalized * interpVelocity * Time.deltaTime);
transform.position = Vector3.Lerp( transform.position, targetPos + offset, 0.25f);
}
}
}
source unity2d camera follow script
The -= in these lines:
camX = rigidbody.transform.position.x -=10;
camY = rigidbody.transform.position.y -=10;
is wrong. The -= will attempt to modify the rigidbody.transform.position. You just want -.
However, as it stands, the camera won't track changes in the target's Z position, nor will it track properly if the camera is rotated. To get the correct position you need (in vectors):-
cam_pos = target_pos - dist_to_target * cam_look_at