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How to make a ground object follow a flying object in unity?

I'm trying to make an object on the ground follow a flying object, for example a drone leading a human (for now i'm just using shapes - a cube and a capsule). My cube follows the capsule like i desire but i want the cube to follow the capsule on the ground only, rather than go up on the y-axis with the capsule. Right now, it follows the capsule everywhere, I want the capsule to lead while the cube follows along on the ground.
I have done some research on Google and Youtube but I have not seen any results. Please let me know how I can achieve this.
This is the code script attached to the cube(ground object)
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class follow_target : MonoBehaviour
{
public Transform mTarget;
float mSpeed = 10.0f;
const float EPSILON = 0.1f;
Vector3 mLookDirection;
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
mLookDirection = (mTarget.position - transform.position).normalized;
if((transform.position - mTarget.position).magnitude > EPSILON)
transform.Translate(mLookDirection * Time.deltaTime * mSpeed);
}
}

If the ground is planar, you can just set the y component to 0 (or whatever the ground y vector is).
If the ground changes in topology, you can do a raycast down from the capsule to get the hit point (vector3). You can use the hit point y component for the height. After that you will need to set the cubes rotation so that it is aligned to the ground. You could do that with a raycast as well, there are a number of examples of that online.
I hope that helps get you in the right direction.

Assuming a flat ground on Y = 0
either make sure your objects sticks to the ground so set
private const float EPSILONSQR = EPSILON * EPSILON;
void Update()
{
var difference = mTarget.position - transform.position;
mLookDirection = difference.normalized;
if(difference.sqrmagnitude > EPSILONSQR)
{
// In general be aware that Translate by default moves in the
// objects own local space coordinates so you probably would rather
// want to use Space.World
transform.Translate(mLookDirection * Time.deltaTime * mSpeed, Space.World);
var pos = transform.position;
// reset the Y back to the ground
pos.y = 0;
transform.position = pos;
}
}
or simply already map the direction down on the XZ plane (ignoring any difference in Y) like
private const float EPSILONSQR = EPSILON * EPSILON;
void Update()
{
var difference = mTarget.position - transform.position;
mLookDirection = difference.normalized;
// simply ignore the difference in Y
// up to you if you want to normalize the vector before or after doing that
mLookDirection.y = 0;
if(difference.sqrmagnitude > EPSILONSQR)
{
transform.Translate(mLookDirection * Time.deltaTime * mSpeed, Space.World);
}
}

Unity camera follows player script

I'm pretty new to Unity. I tried to create a script that the camera would follow the actor (with a little difference). Is there a way to improve the code? It works just fine. But I wonder if I did it the best way. I want to do it about as I wrote, so if you have any tips. Thank you
Maybe change Update to FixedUpdate ?
public GameObject player;
// Start is called before the first frame update
void Start()
{
player = GameObject.Find("Cube"); // The player
}
// Update is called once per frame
void Update()
{
transform.position = new Vector3(player.transform.position.x, player.transform.position.y + 5, player.transform.position.z - 10);
}

Making the camera following the player is quite straight forward.
Add this script to your main camera.
Drag the reference of the player object to the script and then you are done.
You can change the values in the Vector 3 depending on how far you want the camera to be from the player.
using UnityEngine;
public class Follow_player : MonoBehaviour {
public Transform player;
// Update is called once per frame
void Update () {
transform.position = player.transform.position + new Vector3(0, 1, -5);
}
}

Follows player in the back constantly when the player rotates, no parenting needed, with smoothing.
Piece of Knowledges:
Apparently, Quaternion * Vector3 is going to rotate the point of the Vector3 around the origin of the Vector3 by the angle of the Quaternion
The Lerp method in Vector3 and Quaternion stand for linear interpolation, where the first parameter gets closer to the second parameter by the amount of third parameter each frame.
using UnityEngine;
public class CameraFollow : MonoBehaviour
{
public Transform target;
public float smoothSpeed = 0.125f;
public Vector3 locationOffset;
public Vector3 rotationOffset;
void FixedUpdate()
{
Vector3 desiredPosition = target.position + target.rotation * locationOffset;
Vector3 smoothedPosition = Vector3.Lerp(transform.position, desiredPosition, smoothSpeed);
transform.position = smoothedPosition;
Quaternion desiredrotation = target.rotation * Quaternion.Euler(rotationOffset);
Quaternion smoothedrotation = Quaternion.Lerp(transform.rotation, desiredrotation, smoothSpeed);
transform.rotation = smoothedrotation;
}
}

This will always follow the player from the same direction, and if the player rotates it will still stay the same. This may be good for top-down or side-scrolling view, but the camera setup seems to be more fitting for 3rd person, in which case you'd want to rotate the camera when the player turns.
The easiest way to do this is actually not with code alone, simply make the camera a child of the player object, that way its position relative to the player will always stay the same!
If you do want to do it through code, you can change the code to be like this:
void Update()
{
Vector3 back = -player.transform.forward;
back.y = 0.5f; // this determines how high. Increase for higher view angle.
transform.position = player.transform.position - back * distance;
transform.forward = player.transform.position - transform.position;
}
You get the direction of the back of the player (opposite of transform's forward). Then you increase the height a little so the angle will be a bit from above like in your example. Last you set the camera's position to be the player's position and add the back direction multiplied by the distance. That will place the camera behind the player.
You also need to rotate the camera so it points at the player, and that's the last line - setting the camera's forward direction to point at the player.

Here is just another option. I always find it easier to have the variables which are populated in the inspector so you can adjust it and fine tune it as needed.
public GameObject player;
[SerializeField]
private float xAxis, yAxis, zAxis;
private void Update()
{
transform.position = new Vector3(player.transform.position.x + xAxis, player.transform.position.y + yAxis, player.transform.position.z + zAxis);
}

How to check ground for unity2d platformer game

I am trying to make a 2d plat-former where you see the player from the side. I want him to be continuously moving and you have to press space at the right time so he doesn't fall. Right now everything works but he doesn't collide with the ground. I want it to be like he's running behind a wall so I want to ignore a certain layer I have made and collide with the boxes below that. So far I have tried ray casting, watched multiple tutorials, and did box collisions. Box collisions worked but to get all the platforms counted as solid I'd need like 50 box colliders. Here is my current code:
public int playerSpeed = 10;
public int playerJumpPower = 1250;
public float moveX;
public float playerYSize = 2;
public LayerMask mainGround;
public float playerFallSpeed = 5;
void Awake(){
}
// Update is called once per frame
void Update()
{
RaycastHit2D hit = Physics2D.Raycast(transform.position, new Vector2(10, 0));
if(hit.distance < 0.7f){
print("hi");
}
Vector3 characterTargetPosition = new Vector3(transform.position.x + playerSpeed, transform.position.y, transform.position.z);
transform.position = Vector3.Lerp(transform.position, characterTargetPosition, playerSpeed * Time.deltaTime);
if(Input.GetKeyDown("space")){
// float playerTargetPosY = transform.position.y + playerJumpPower;
// Vector3 characterTargetPosition = new Vector3(transform.position.x, playerTargetPosY, transform.position.z);
// transform.position = Vector3.Lerp(transform.position, characterTargetPosition, playerJumpPower * Time.deltaTime);
gameObject.GetComponent<Rigidbody2D>().AddForce(Vector2.up * playerJumpPower);
}
//PlayerMove();
}
I have a rigidBody2D on my player so right now he just falls through the ground but the jump does work. If there is any easy way to do this. Like some script, a tutorial, or website I'm open for it. Please help.

Do you have a Rigidbody2D in your player? Things that will move usually have to have a RigidBody
(sorry for posting this as an answer. Cant comment yet)
EDIT:
try this:
Rigidbody2D rb;
void Awake()
{
rb = GetComponent<Rigidbody2D>();
}
//Physics usually are done in FixedUpdate to be more constant
public void FixedUpdate(){
if (Input.GetKeyDown("space"))
{
if(!rb.simulated)
//player can fall
rb.simulated = true;
rb.AddForce(Vector2.up * playerJumpPower);
}
else
{
//third argument is the distance from the center of the object where it will collide
//therefore you want the distance from the center to the bottom of the sprite
//which is half of the player height if the center is actually in the center of the sprite
RaycastHit2D hit = Physics2D.Raycast(transform.position, -Vector2.up, playerYSize / 2);
if (hit.collider)
{
//make player stop falling
rb.simulated = false;
}
}
}
If the player is the only thing that will collide with something you can just take out the colliders from the object that the player will not collide with.
Else you can check for the layer of the collided object with hit.collider.gameObject.layer and decide if the player will collide with that layer or not
(note that you have to compare with the index of the layer. If you want to get the index by its name you can use LayerMask.NameToLayer(/*layer name*/))
you will have to do rb.simulated = true everytime you want to do something with the RigidBody (like AddForce())
hope it helped :)

Clamping an object axis in Vuforia AR camera

screenshot hereI want to clamp Y-axis on a cube. I can do it in Unity camera. But, it does not react correctly when I am using it in Vuforia camera.
My problem was that the cube follows the camera. I would like the cube to stay in its position and ignore the AR camera position. I sense it has something to do with WorldtoViewpoint but I cannot figure it out. Can you teach me how to do this please? thankyou
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class ClampMovementController : MonoBehaviour
{
// Start is called before the first frame update
void Start()
{
}
// Update is called once per frame
void Update()
{
Vector3 pos = transform.localPosition;
pos.y = Mathf.Clamp(transform.position.y, 0f, 0f);
transform.localPosition = pos;
}
}

This is my solution:
Actually its very simple. The INcorrect concept was my object attached to the AR camera, hence, object position is always moving related to camera position. Now. In order to make the object stays in its place. I need to get its localPosition. First. Store the localposition in Vector3 pos. And then do modification on Vector3 pos. At last, reassign the new value to the object localposition.
public class ClampMovementController : MonoBehaviour
{
public float currentPos;
public GameObject capsule;
void Update()
{
//store the value of object localPosition
Vector3 pos = capsule.transform.localPosition;
//modification on the value
pos.y = Mathf.Clamp(pos.y, currentPos, currentPos);
//rerassign the new value to the object localPosition
capsule.transform.localPosition = pos;
}
}

First of all your cube is moving with the camera because your image target is child of your ARCamera. Therefore, when you move the camera image target moves, then your cube moves as well. Make sure your ImageTarget has no parent.
I did not understand why you have to lock any movement in Y axis. I guess you are doing something wrong with lean touch when you move object. I have not used lean touch but i have achieved this with keyboard inputs. You can convert it to lean touch by modifying following script. Just add these line to your ImageTarget's DefaultTrackableEventHandler script:
//Variables for getting capsule and checking if ImageTarget is tracked
private bool isTracked = false;
private GameObject capsule;
Then create an Update method for getting input from user like this.
void Update()
{
if(isTracked)
{
if(Input.GetKey(KeyCode.W))
{
//using forward for moving object in z axis only.
//Also using local position since you need movement to be relative to image target
//Global forward can be very different depending on your World Center Mode
capsule.transform.localPosition += Vector3.forward * Time.deltaTime;
}
else if (Input.GetKey(KeyCode.S))
{
capsule.transform.localPosition -= Vector3.forward * Time.deltaTime;
}
if (Input.GetKey(KeyCode.A))
{
//Using Vector3.left and right to be make sure movement is in X axis.
capsule.transform.localPosition += Vector3.left * Time.deltaTime;
}
else if (Input.GetKey(KeyCode.D))
{
capsule.transform.localPosition += Vector3.right * Time.deltaTime;
}
}
}
As you can see there is no movement in Y axis because i used forward, left and right vectors to make sure movement in in only X and Y axis.
Last you have to make sure isTracked is updated. In order to do that you have to add isTracked = false; in OnTrackingLost method and isTracked = true; in OnTrackingFound method. Good luck!

Spawn bombs and throw them to the player in Unity

I got a small arena where the player can move on. At the sides of the area there are spawners. These spawners instantiate bombs and should throw them at the player.
For the direction I actually use
transform.lookAt(playerTransform);
So this is a rough map
So the spawners are rotating around the map. They move from one point to the next point.
My bomb object got a rigidbody attached and the gravity is activated. I just need to find out how to make a spawner throwing a bomb to the player.
public class BombSpawner : MonoBehaviour
{
[Range(0, 3)]
[SerializeField]
private int nextPointIndex; // set the first targetpoint
private Vector3[] targetPoints = {
new Vector3(-15,0,15),
new Vector3(15,0,15),
new Vector3(15,0,-15),
new Vector3(-15,0,-15)};
private float movementSpeed = 10;
GameObject bombPrefab;
Transform player;
private void Start()
{
bombPrefab = Resources.Load(StringCollection.BOMB) as GameObject;
player = Globals.GetPlayerObject().transform;
}
private void Update()
{
transform.LookAt(player); // set the object rotation
Vector3 nextPoint = targetPoints[nextPointIndex]; // get the target point
transform.position = Vector3.MoveTowards(transform.position, nextPoint, movementSpeed * Time.deltaTime); // move the spawner
if (transform.position == nextPoint) // point reached? set a new point
{
if (nextPointIndex < targetPoints.Length - 1)
nextPointIndex++;
else
nextPointIndex = 0;
}
}
}
So I could write a method like this
void SpawnBomb()
{
GameObject spawnedBomb = Instantiate(bombPrefab);
}
but how do I achieve the throwing mechanic? For a first try, the targetPoint is player.position that should be fine.

You need to get the direction from spawner to the current position of the target, spawn the bomb and add force to that bomb using the direction you just got.
In order to do this you should substract your spawner's position from your target position.
Vector3 dir = target.transform.position - transform.position;
Now that you have the direction you can spawn your bomb and AddForce() to it. To add force you need to call the Rigidbody component of your spawned Bomb, like this:
spawnedBomb.GetComponent<Rigidbody>().AddForce(dir.normalized * force, ForceMode.Impulse);
Where dir is the direction towards the target (normalized - so the distance doesn't matter) and force is pretty much the speed of the bomb.
Here you can read more about Rigidbody.AddForce.