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Zooming out the camera so that it can see all objects

I have a list of objects, these are blue stickmen on the video, I need to make the camera move away by itself and all objects (blue stickmen) always fit into it, you need to take into account that there will be more and more objects each time, so the camera should be dynamic and adapt itself to all objects
https://youtube.com/shorts/x3uSO2L22Kc?feature=share

Practical solution for any camera angle and objects positions
The idea here is fairly simple.
At each step we check if each object is inside of camera view or is camera too far away, then we simply adjust the camera position towards a better one.
Step by step, our camera will follow target objects dynamically, and when stabilized, all target objects will be captured by camera.
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CameraAutoFitSmooth : MonoBehaviour
{
public int maxNumberOfObjs = 100;
public GameObject objPrefab;
public float maxInitRange = 10f;
public float minCameraHeight = 1f;
public float maxCameraMoveSpeed = 9f;
public float marginalPos = 0.1f;
[HideInInspector]
public List<Transform> objs = new List<Transform>();
Camera cam;
void Start()
{
cam = Camera.main;
}
void Update()
{
if (Input.GetKeyDown(KeyCode.Space))
RandomObjs();
}
// Randomly regenerate objects
void RandomObjs()
{
int nowNumberOfObjs = Random.Range(0, maxNumberOfObjs);
for (int i = objs.Count - 1; i > nowNumberOfObjs; i--)
{
Destroy(objs[i].gameObject);
objs.RemoveAt(i);
}
for (int i = objs.Count; i <= nowNumberOfObjs; i++)
objs.Add(Instantiate(objPrefab).transform);
foreach (var obj in objs)
obj.position = Random.insideUnitSphere * maxInitRange;
}
void LateUpdate()
{
SetCameraFitPosition(Time.deltaTime);
}
void SetCameraFitPosition(float deltaTime)
{
Vector3 targetCamPos = cam.transform.position;
if (objs.Count == 1)
{
targetCamPos = objs[0].position - minCameraHeight * cam.transform.forward;
}
else if (objs.Count > 1)
{
float minInsideDiff = 1f, maxOutsideDiff = 0f;
Vector3 center = Vector3.zero;
foreach (var obj in objs)
{
Vector3 screenPos = GetScreenPos(obj.position);
if (IsInsideView(screenPos))
minInsideDiff = Mathf.Min(minInsideDiff, CalculateInsideDiff(screenPos.x), CalculateInsideDiff(screenPos.y), CalculateInsideDiff(screenPos.z));
else
maxOutsideDiff = Mathf.Max(maxOutsideDiff, CalculateOutsideDiff(screenPos.x), CalculateOutsideDiff(screenPos.y), CalculateOutsideDiff(screenPos.z));
center += obj.position;
}
center /= objs.Count;
float nowHeight = Vector3.Project(cam.transform.position - center, cam.transform.forward).magnitude;
float maxDiff = maxOutsideDiff > 0f ? maxOutsideDiff : -minInsideDiff;
float finalHeight = Mathf.Max(nowHeight + maxDiff * maxCameraMoveSpeed, minCameraHeight);
targetCamPos = center - finalHeight * cam.transform.forward;
}
cam.transform.position = Vector3.MoveTowards(cam.transform.position, targetCamPos, maxCameraMoveSpeed * deltaTime);
}
Vector3 GetScreenPos(Vector3 pos)
{
return cam.WorldToViewportPoint(pos);
}
float CalculateOutsideDiff(float pos)
{
float diff = 0f;
if (pos > 1f + marginalPos)
diff = pos - 1f;
else if (pos < -marginalPos)
diff = -pos;
return diff;
}
float CalculateInsideDiff(float pos)
{
float diff = 0f;
if (pos < 1f - marginalPos && pos > marginalPos)
diff = Mathf.Min(1f - pos, pos);
return diff;
}
bool IsInsideView(Vector3 screenPoint)
{
return screenPoint.z > 0f && screenPoint.x > 0f && screenPoint.x < 1 && screenPoint.y > 0f && screenPoint.y < 1;
}
}
If you need more info feel free to contact me :) Cheers!

The following script will position a perspective camera in a top down view, so that all tracked GameObjects (objs) are visible.
It is assumed that the objects are on the zero xz plane and are points, so their actual dimensions are not taken into account. There must be at least one tracked object. The objects may not be spaced in such a way that would require the cameras height to exceed the maximum floating point value.
public GameObject[] objs;//objects that must be fitted
private Camera cam;
float recXmin, recXmax, recYmin, recYmax;
Vector3 center;
void Start()
{
cam = Camera.main;
cam.transform.rotation = Quaternion.Euler(90, 0, 0);
}
void LateUpdate()
{
recXmin = objs[0].transform.position.x;
recXmax = objs[0].transform.position.x;
recYmin = objs[0].transform.position.z;
recYmax = objs[0].transform.position.z;
center = Vector3.zero;
foreach (GameObject obj in objs)
{
if (obj.transform.position.x < recXmin)
{
recXmin = obj.transform.position.x;
}
if (obj.transform.position.x > recXmax)
{
recXmax = obj.transform.position.x;
}
if (obj.transform.position.z < recYmin)
{
recYmin = obj.transform.position.z;
}
if (obj.transform.position.z > recYmax)
{
recYmax = obj.transform.position.z;
}
}
float horizontalHeight = (recYmax - recYmin) / 2 / Mathf.Tan(Mathf.Deg2Rad * cam.fieldOfView / 2);
float verticalHeight = (recXmax - recXmin) / 2 / Mathf.Tan(Mathf.Deg2Rad * Camera.VerticalToHorizontalFieldOfView(cam.fieldOfView, cam.aspect) / 2);
float finalHeight = horizontalHeight > verticalHeight ? horizontalHeight : verticalHeight;
center = new Vector3(recXmin + (recXmax - recXmin) / 2, finalHeight, recYmin + (recYmax - recYmin) / 2);
cam.transform.position = center;
}
void OnDrawGizmos()
{
Gizmos.color = Color.red;
Gizmos.DrawLine(new Vector3(recXmin, 0, recYmin), new Vector3(recXmin, 0, recYmax));
Gizmos.DrawLine(new Vector3(recXmax, 0, recYmin), new Vector3(recXmax, 0, recYmax));
Gizmos.color = Color.green;
Gizmos.DrawLine(new Vector3(recXmin, 0, recYmin), new Vector3(recXmax, 0, recYmin));
Gizmos.DrawLine(new Vector3(recXmin, 0, recYmax), new Vector3(recXmax, 0, recYmax));
Gizmos.color = Color.blue;
Gizmos.DrawSphere(center, 0.5f);
}
the script determines the "bounding square" formed by all tracked objects
the bounding square is assumed to be the basis of a pyramid with the camera at its peak
using trigonometry the height of the camera can be calculated, by taking into account the known length of the pyramid's base side and the cameras field of view
the calculation is made twice for the cameras horizontal and vertical field of view
the greater of these two values is then selected
lastly the camera is position into the middle of the pyramids base and at the determined height, so that it ends up at the pyramids peak

How can I add equal gap between gameobjects?

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class DropDown : MonoBehaviour
{
public GameObject dropdownPrefab;
public int numberOfObjects;
public float speed = 1.5f;
public float duration = 5f;
public Vector3 startPos;
public Vector3 endPos;
public float distanceToMove = 2f;
public float gap;
private List<GameObject> dropDownObjects = new List<GameObject>();
private List<Vector3> endPositions = new List<Vector3>();
private void Start()
{
for (int i = 0; i < numberOfObjects; i++)
{
dropDownObjects.Add(Instantiate(dropdownPrefab, transform.parent));
endPositions.Add(new Vector3(dropDownObjects[i].transform.position.x,
dropDownObjects[i].transform.position.y + i + 2,
dropDownObjects[i].transform.position.z) - Vector3.up * distanceToMove);
}
startPos = dropDownObjects[0].transform.position;
}
private void OnMouseDown()
{
StartCoroutine(StartDropObjects());
}
private IEnumerator StartDropObjects()
{
for (int i = 0; i < dropDownObjects.Count; i++)
{
// Random wait period before rotation starts
if (i == 0)
{
//yield return new WaitForSeconds(0);
}
else
{
//yield return new WaitForSeconds(Random.Range(0, 2f));
}
yield return new WaitForSeconds(2f);
StartCoroutine(Drop(dropDownObjects[i].transform, duration, endPositions[i]));
}
}
private IEnumerator Drop(Transform objectToDrop, float duration, Vector3 endpos)
{
float t = 0.0f;
while (t < duration)
{
t += Time.deltaTime;
objectToDrop.transform.position = Vector3.MoveTowards(objectToDrop.transform.position, endpos, speed * Time.deltaTime);
yield return null;
}
}
}
The objects should be moving down but when I'm adding the gap in this case the gap is i + 2 for example if I = 0 then the gap is 2 then I = 1 so the gap will be 3 then I = 2 the gap is 4.
endPositions.Add(new Vector3(dropDownObjects[i].transform.position.x,
dropDownObjects[i].transform.position.y + i + 2,
dropDownObjects[i].transform.position.z) - Vector3.up * distanceToMove);
But I want to have equal gaps between the objects. For example if I will set the gap value to 1 there will be equal spaces/gaps between the objects and if the gap value is 5 then equal 5 between each two objects.
The problem now is that I getting higher each time by 1 so the gaps are not equal.
And also the objects are moving up and not down when I'm doing: + i + 2
In the screenshot the objects moved up instead down and the top two objects seems too close to each other. And the gaps are not equal.
But the idea is when the objects are moving to the target destination endPositions that each one will move to his on endPosition depending on the gap.
So in the end the objects should be like this :
The first one is the one on the most bottom. The last one is the one on the top.
The first dropDownObjects[0] object moved to his endPosition the farest endPosition. In this case distanceToMove is set to 2.
Then dropDownObjects1 is moving to his distanceToMove - the gap. And so on. This is the logic that in the end after all objects move they will have equal gaps.
And the first moved object is the one that should get to the distnaceToMove.

Problem is not here:
endPositions.Add(new Vector3(dropDownObjects[i].transform.position.x,
dropDownObjects[i].transform.position.y + i + 2,
dropDownObjects[i].transform.position.z) - Vector3.up * distanceToMove);
But here:
private IEnumerator Drop(Transform objectToDrop, float duration, Vector3 endpos)
{
float t = 0.0f;
while (t < duration)
{
t += Time.deltaTime;
objectToDrop.transform.position = Vector3.MoveTowards(objectToDrop.transform.position, endpos, speed * Time.deltaTime);
yield return null;
}
}
Because you are using the same duration for all objects, but they have a different distance. The last objects just don't have time to finish their movement.
You can check this by changing your method Drop(...) to this code:
private IEnumerator Drop(Transform objectToDrop, float duration, Vector3 endpos)
{
while (objectToDrop.transform.position != endpos)
{
objectToDrop.transform.position = Vector3.MoveTowards(objectToDrop.transform.position, endpos, speed * Time.deltaTime);
yield return null;
}
}

I would change how you're determining your endPositions to make it easier to configure.
I would define a starting distance and a max distance and you can calculate the gap programmatically by interpolating between the starting distance and minDistanceToMove maxDistanceToMove using Mathf.Lerp with a t of (float)i/(numberOfObjects-1):
public float minDistanceToMove = 0.5f;
public float maxDistanceToMove = 2f;
private void Start()
{
for (int i = 0; i < numberOfObjects; i++)
{
dropDownObjects.Add(Instantiate(dropdownPrefab, transform.parent));
float t = (float)i/(numberOfObjects-1);
float distDown = Mathf.Lerp(minDistanceToMove,maxDistanceToMove,t);
endPositions.Add(new Vector3(dropDownObjects[i].transform.position.x,
dropDownObjects[i].transform.position.y,
dropDownObjects[i].transform.position.z) - Vector3.up * distDown);
}
startPos = dropDownObjects[0].transform.position;
}
Alternatively, you can set only a minDistanceToMove and a gap size and then calculate distDown that way:
public float minDistanceToMove = 0.5f;
public float gapSize = 0.5f;
private void Start()
{
for (int i = 0; i < numberOfObjects; i++)
{
dropDownObjects.Add(Instantiate(dropdownPrefab, transform.parent));
float distDown = minDistanceToMove + gapSize * i;
endPositions.Add(new Vector3(dropDownObjects[i].transform.position.x,
dropDownObjects[i].transform.position.y,
dropDownObjects[i].transform.position.z) - Vector3.up * distDown);
}
startPos = dropDownObjects[0].transform.position;
}
Either way, you then need to change Drop to last for however long it takes for the panel to drop to its destination:
private IEnumerator Drop(Transform objectToDrop, float duration, Vector3 endpos)
{
// duration is unused. It is in the method signature here to avoid
// confusion when swapping with the alternative below
while (objectToDrop.transform.position != endPos)
{
objectToDrop.transform.position = Vector3.MoveTowards(
objectToDrop.transform.position, endpos, speed * Time.deltaTime);
yield return null;
}
}
Alternatively, you can make each panel take the given duration and calculate the speed necessary to traverse the distance:
private IEnumerator Drop(Transform objectToDrop, float duration, Vector3 endpos)
{
float mySpeed = Vector3.Distance(
objectToDrop.transform.position, endpos) / duration;
while (objectToDrop.transform.position != endPos)
{
objectToDrop.transform.position = Vector3.MoveTowards(
objectToDrop.transform.position, endpos, mySpeed * Time.deltaTime);
yield return null;
}
}

Unity Follow The Leader Behavior

I asked this question two years ago. Not ever having success, I abandoned the idea until recently.
I have since been able to semi-fix / replicate the mechanic. However, all the objects seem to jump to their next position, with some duplicating their "leader's" position.
The orange is the head, with the body parts being green.
As you can see from the commented out code below, I have tried multiple permutations to get the children to follow their leader smoothly with the distance between each body-part just being the circle colliders radius.
My thought was, if the "leader" has moved the distance of the radius, then the follower can move towards the leaders old position. This give the leader time to move.
But the only one that seems to semi work, is the un-commented one.
Can anyone see the problem?
FollowTheLeader.cs
public class FollowTheLeader : MonoBehaviour
{
[Header("Head")]
public GameObject bodyPart;
public int bodyLength = 6;
[Header("Move Speed")]
[Range(0.25f, 2.0f)] public float moveMin = 0.5f;
[Range(0.25f, 2.0f)] public float moveMax = 2.0f;
[Header("Change Directions")]
[Range(0.25f, 2.0f)] public float changeMin = 0.5f;
[Range(0.25f, 2.0f)] public float changeMax = 2.0f;
[SerializeField]
private Vector2 oldPosition;
public Vector2 OldPosition { get => oldPosition; set => oldPosition = value; }
[SerializeField]
private Vector2 moveDirection = new Vector2(0, -1);
public Vector2 MoveDirection { get => moveDirection; set => moveDirection = value; }
[Header("Child")]
public int index;
public bool isChild;
public FollowTheLeader leader;
public float leaderDistance;
private CircleCollider2D m_collider2D;
private Rigidbody2D body2d;
private float moveSpeed;
private float moveTimePassed;
private float changeDirInterval;
private void Awake()
{
m_collider2D = GetComponent<CircleCollider2D>();
body2d = GetComponent<Rigidbody2D>();
AddBodyParts();
DefineDirection(moveDirection);
}
private void AddBodyParts()
{
if (isChild || bodyPart == null)
return;
//The head will generate its body parts. Each body part will have reference to the one before it.
FollowTheLeader temp = this;
for (int i = 1; i <= bodyLength; i++)
{
GameObject bp = Instantiate(bodyPart, transform);
bp.transform.SetParent(null);
//bp.transform.position = transform.position;
bp.transform.position = new Vector2(i * m_collider2D.radius, 0);
bp.name = $"Body {i}";
FollowTheLeader c = bp.AddComponent<FollowTheLeader>();
c.isChild = true;
c.index = i;
c.OldPosition = bp.transform.position;
c.leader = temp;
// cache the parent for the next body part
temp = c;
}
}
private void Start()
{
OnNewDirection();
}
private void FixedUpdate()
{
//Store the old postion for the next child
OldPosition = body2d.position;
// If child
if (isChild)
{
// Calculate the leaders distance
leaderDistance = Vector2.Distance(OldPosition, leader.OldPosition);
// We only want to move if the parent is as far away as the m_collider2D.radius.
if (leaderDistance < m_collider2D.radius)
return;
// BARELY ANY MOVEMENT
//body2d.MovePosition(leader.OldPosition.normalized);
//body2d.MovePosition(leader.OldPosition.normalized * moveSpeed);
//body2d.MovePosition(leader.OldPosition.normalized * moveSpeed * Time.deltaTime);
//body2d.MovePosition(leader.OldPosition.normalized * parentDistance * moveSpeed * Time.deltaTime);
//body2d.MovePosition(leader.OldPosition.normalized * m_collider2D.radius * parentDistance * moveSpeed * Time.deltaTime);
//FLYS ALL OVER THE PLACE
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized);
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized * moveSpeed);
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized * parentDistance * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized * m_collider2D.radius * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition.normalized * m_collider2D.radius * parentDistance * moveSpeed * Time.deltaTime);
// BARELY ANY MOVEMENT
//body2d.MovePosition(leader.OldPosition * moveSpeed);
//body2d.MovePosition(leader.OldPosition * moveSpeed * Time.deltaTime);
//body2d.MovePosition(leader.OldPosition * parentDistance * moveSpeed * Time.deltaTime);
//body2d.MovePosition(leader.OldPosition * m_collider2D.radius * parentDistance * moveSpeed * Time.deltaTime);
//FLYS ALL OVER THE PLACE
//body2d.MovePosition(body2d.position + leader.OldPosition);
//body2d.MovePosition(body2d.position + leader.OldPosition * moveSpeed);
//body2d.MovePosition(body2d.position + leader.OldPosition * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition * parentDistance * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition * m_collider2D.radius * moveSpeed * Time.deltaTime);
//body2d.MovePosition(body2d.position + leader.OldPosition * m_collider2D.radius * parentDistance * moveSpeed * Time.deltaTime);
// KINDA FOLLOWS BUT ALL SEEM TO JUMP INTO THE SAME POSITION AS SEEN IN THE GIF
body2d.MovePosition(leader.OldPosition);
return;
}
// HEAD ONLY
// Countdown to next direction change
moveTimePassed += Time.deltaTime;
if (moveTimePassed >= changeDirInterval)
{
OnNewDirection();
}
// Calculate the next position
body2d.MovePosition(body2d.position + MoveDirection.normalized * moveSpeed * Time.deltaTime);
}
public void OnNewDirection()
{
moveTimePassed = 0;
moveSpeed = Random.Range(moveMin, moveMax);
changeDirInterval = Random.Range(changeMin, changeMax);
RandomDirection();
}
private void RandomDirection()
{
switch (Random.Range(0, 4))
{
case 0:
DefineDirection(Vector2.up);
break;
case 1:
DefineDirection(Vector2.right);
break;
case 2:
DefineDirection(Vector2.down);
break;
case 3:
DefineDirection(Vector2.left);
break;
default:
DefineDirection(Vector2.down);
break;
}
}
public void DefineDirection(Vector2 direction)
{
if (direction.Equals(Vector2.up))
{
MoveDirection = Vector2.up;
}
if (direction.Equals(Vector2.down))
{
MoveDirection = Vector2.down;
}
if (direction.Equals(Vector2.left))
{
MoveDirection = Vector2.left;
}
if (direction.Equals(Vector2.right))
{
MoveDirection = Vector2.right;
}
}
}

Many different ways you can approach it but let me show you one way.
Snake - moves the leader forward, creates new points in the path, manages minions
Path - ring buffer with of all the points
Minion - follow the path based on the distance from the leader
Here's an example with gizmos showing:
Green is the leader
Red is the head of the path
Blue is the tail of the path
The snake is where the main logic is at.
The snake moves forward automatically. When the distance between the leader and the last point is greater than RADIUS we create a new point. We then move all of the minions along the path of points.
public class Snake : MonoBehaviour
{
public const float RADIUS = 1f; // distance between minions
public const float MOVE_SPEED = 1f; // movement speed
public Vector2 dir = Vector2.up; // movement direction
public float headDist = 0f; // distance from path 'head' to leader (used for lerp-ing between points)
public Path path = new Path(1); // path points
public List<Minion> minions = new List<Minion>(); // all minions
public Minion Leader => minions[0];
void Awake()
{
path.Add(this.transform.position);
AddMinion(new Knight());
}
void AddMinion(Minion minion)
{
// Initialize a minion and give it an index (0,1,2) which is used as offset later on
minion.Init(minions.Count);
minions.Add(minion);
minion.MoveOnPath(path, 0f);
// Resize the capacity of the path if there are more minions in the snake than the path
if (path.Capacity <= minions.Count) path.Resize();
}
void FixedUpdate()
{
MoveLeader();
MoveMinions();
}
void MoveLeader()
{
// Move the first minion (leader) towards the 'dir'
Leader.transform.position += ((Vector3)dir) * MOVE_SPEED * Time.deltaTime;
// Measure the distance between the leader and the 'head' of that path
Vector2 headToLeader = ((Vector2)Leader.transform.position) - path.Head().pos;
// Cache the precise distance so we can reuse it when we offset each minion
headDist = headToLeader.magnitude;
// When the distance between the leader and the 'head' of the path hits the threshold, spawn a new point in the path
if (headDist >= RADIUS)
{
// In case leader overshot, let's make sure all points are spaced exactly with 'RADIUS'
float leaderOvershoot = headDist - RADIUS;
Vector2 pushDir = headToLeader.normalized * leaderOvershoot;
path.Add(((Vector2)Leader.transform.position) - pushDir);
// Update head distance as there is a new point we have to measure from now
headDist = (((Vector2)Leader.transform.position) - path.Head().pos).sqrMagnitude;
}
}
void MoveMinions()
{
float headDistUnit = headDist / RADIUS;
for (int i = 1; i < minions.Count; i++)
{
Minion minion = minions[i];
// Move minion on the path
minion.MoveOnPath(path, headDistUnit);
// Extra push to avoid minions stepping on each other
Vector2 prevToNext = minions[i - 1].transform.position - minion.transform.position;
float distance = prevToNext.magnitude;
if (distance < RADIUS)
{
float intersection = RADIUS - distance;
minion.Push(-prevToNext.normalized * RADIUS * intersection);
}
}
}
}
Path is a ring buffer, Head() gives you the newest point that was added, you can use Head(index) to get the head and offset it in a direction(+/-). Minions use it to fetch points that are just behind the head: path.Head(-1).
public class Path
{
public Vector2[] Points { get; private set; }
public int Capacity => Points.Length;
int head;
public Path(int capacity)
{
head = 0;
Points = new Vector2[capacity];
}
public void Resize()
{
Vector2[] temp = new Vector2[Capacity * 2];
for (int i = 0; i < temp.Length; i++)
{
temp[i] = i < Capacity ? Head(i + 1) : Tail();
}
head = Capacity - 1;
Points = temp;
}
public void Add(Vector2 pos)
{
int prev = Mod(head, Capacity);
Next();
int next = Mod(head, Capacity);
Points[next].pos = pos;
}
public Vector2 Head()
{
return Points[head];
}
public Vector2 Head(int index)
{
return Points[Mod(head + index, Capacity)];
}
public Vector2 Tail()
{
return Points[Mod(head + 1, Capacity)];
}
public Vector2 Tail(int index)
{
return Points[Mod(head + 1 + index, Capacity)];
}
void Next()
{
head++;
head %= Capacity;
}
int Mod(int x, int m)
{
return (x % m + m) % m;
}
}
A minion contains an index, which tells us the placement of the minion within the snake (first, second, third). We use this index to get the two points needed for interpolation. path.Head(-0) will give us the leader's point. path.Head(-1) will give us the first minion's point.
public class Minion : MonoBehaviour
{
int index;
public Init(int index)
{
this.index = index;
}
// Move the minion along the path
public void MoveOnPath(Path path, float dist)
{
Vector2 prev = path.Head(-index);
Vector2 next = path.Head(-index + 1);
// Interpolate the position of the minion between the previous and the next point within the path. 'dist' is the distance between the 'head' of the path and the leader
this.transform.position = Vector2.Lerp(prev.pos, next.pos, dist);
}
// Push the minion to avoid minions stepping on each other
public void Push(Vector2 dir)
{
this.transform.position += (Vector3)dir;
}
}
I've stripped out a lot of code to make the example simpler. I hope you get the basic idea and will be able to implement your own solution.

I tried recreating this scenario in 3D and got somewhat the same behaviour as yours.
First, you want to use twice the radius, as each child would otherwise overlap half of the parent since it is the center of the circle that is being moved.
I used a different approach to move the children than you did. The result is a smooth, snake-like motion:
The code is simple enough:
First I rotate the child to point its forward axis at the leader's position
Second the length from the current position to the desired position is calculated. I subtract twice the radius, as the new position would otherwise result in overlapping spheres
I use the translate function to move the GameObject in the forward direction using the calculated magnitude.
// KINDA FOLLOWS BUT ALL SEEM TO JUMP INTO THE SAME POSITION AS SEEN IN THE GIF
//body2d.MovePosition(leader.OldPosition);
transform.LookAt(leader.transform);
float length = leaderDistance - (m_collider2D.radius * 2);
transform.Translate(transform.forward * length, Space.World);
return;
The result is a smooth, predictable motion. You can even turn off kinematic on the rigidbody to enable collisions.
Hope that helped you.

How do I make a pool cue rotate around the cue ball?

I want the pool cue to rotate around the cue ball as the player drags the mouse, I've played some pool games on the internet and they all seem to work this way. This will eventually be a browser game.
This game isn't mine, but it has the basic mechanic that I want (I don't care about the lines that are displayed, I just want the rotate and hit mechanic) https://www.crazygames.com/game/8-ball-billiards-classic
I have tried some orbiting scripts so far, none of them work.
I've tried some scripts that make objects orbit based on time hoping to make it so it orbits with the mouse dragging instead of time. I also can't get the cue to constantly face the cue ball.
This code has gotten me the closest.
public int vertexCount = 40;
public float lineWidth = 0.2f;
public float radius;
public bool circleFillscreen;
//circle variables
static float timeCounter = 0;
float width;
float height;
private LineRenderer lineRenderer;
private void Awake()
{
lineRenderer = GetComponent<LineRenderer>();
SetupCircle();
}
void Update()
{
timeCounter += Time.deltaTime;
float x = Mathf.Cos(timeCounter);
float y = 0;
float z = Mathf.Sin(timeCounter);
}
private void SetupCircle()
{
lineRenderer.widthMultiplier = lineWidth;
if (circleFillscreen)
{
radius = Vector3.Distance(Camera.main.ScreenToWorldPoint(new Vector3(0f, Camera.main.pixelRect.yMax, 0f)),
Camera.main.ScreenToWorldPoint(new Vector3(0f, Camera.main.pixelRect.yMin, 0f))) * 0.5f - lineWidth;
}
float deltaTheta = (2f * Mathf.PI) / vertexCount;
float theta = 0F;
lineRenderer.positionCount = -vertexCount;
for (int i = 0; i < lineRenderer.positionCount; i++)
{
Vector3 pos = new Vector3(radius * Mathf.Cos(theta), radius * Mathf.Sin(theta), 0f);
lineRenderer.SetPosition(i, pos);
theta += deltaTheta;
}
}
#if UNITY_EDITOR
private void OnDrawGizmos()
{
float deltaTheta = (2f * Mathf.PI) / vertexCount;
float theta = 0f;
Vector3 oldPos = Vector3.zero;
for (int i = 0; i < vertexCount + 1; i++)
{
Vector3 pos = new Vector3(radius * Mathf.Cos(theta), 0F,radius * Mathf.Sin(theta));
Gizmos.DrawLine(oldPos, transform.position + pos);
oldPos = transform.position + pos;
theta += deltaTheta;
}
}
#endif
}
Not really getting any error messages, code "works" but doesn't work.

Stuck with collision detection in circle pong in xna

I am making clone of Circle pong game in xna. I am not able to get collision of rotating pad with ball. I can't use farseer physics in this game as it is in mono game.
I found one method for it but it also not seem to work.
private void EllasticCollisionPhysics(Ball ball, GoScreen pad)
{
//find normal vector
Vector2 normal = new Vector2(pad.padV.X - ball.ballRectangle.X, pad.padV.Y - ball.ballRectangle.Y);
//find normal vector's modulus, i.e. length
float normalmod = (float)Math.Sqrt(Math.Pow(normal.X, 2) + Math.Pow(normal.Y, 2));
//find unitnormal vector
Vector2 unitnormal = new Vector2((pad.padV.X - ball.ballRectangle.X) / normalmod, (pad.padV.Y - ball.ballRectangle.Y) / normalmod);
//find tangent vector
Vector2 unittan = new Vector2(-1 * unitnormal.Y, unitnormal.X);
//first ball normal speed before collision
float inormalspeedb = unitnormal.X * velocity.X + unitnormal.Y * velocity.Y;
//first ball tangential speed
float itanspeed = unittan.X * velocity.X + unittan.Y * velocity.Y;
//Calculate normal speeds after the collision
//Calculate first ball Velocity vector components (tangential and normal)
Vector2 inormala = new Vector2(unitnormal.X * inormalspeedb, unitnormal.Y * inormalspeedb);
Vector2 itana = new Vector2(unittan.X * itanspeed, unittan.Y * itanspeed);
//Add Vector components to each balls' Velocity
velocity = Vector2.Add(inormala, itana);

You don't need farseer physics for that, what you need is circle to rectangle collisition funciton.
// circle is object with x,y,r parameters
bool intersects(CircleType circle, RectType rect)
{
circleDistance.x = abs(circle.x - rect.x);
circleDistance.y = abs(circle.y - rect.y);
if (circleDistance.x > (rect.width/2 + circle.r)) { return false; }
if (circleDistance.y > (rect.height/2 + circle.r)) { return false; }
if (circleDistance.x <= (rect.width/2)) { return true; }
if (circleDistance.y <= (rect.height/2)) { return true; }
cornerDistance_sq = (circleDistance.x - rect.width/2)^2 +
(circleDistance.y - rect.height/2)^2;
return (cornerDistance_sq <= (circle.r^2));
}
Added CircleType and RectType
public class CircleType
{
public int x;
public int y;
public decimal r;
}
public class RectType
{
public int x;
public int y;
public int width;
public int height;
}