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How to detect when a cube is directly above another cube?

I am using the Unity Engine with C#.
I have a 1x1 cube which moves forward on a grid of 49, 1x1 cubes (screenshot below) - when I press the start button on the controller.
The movement code for the cube is below.
void MovePlayerCube()
{
transform.Translate(direction * moveSpeed * Time.deltaTime);
}
When this cube passes over a cube with an arrow on it, the cube will change direction to where the arrow is pointing (staying on the same Y axis).
I need to detect the exact point at which the cube is directly over the cube with the arrow on it, and run the 'change direction' code at that point.
I'm currently using Vector3.Distance to check if the X and Z coordinates of the 2 cubes are close enough together (if they are less than 0.03f in distance), I can't check if they are equal due to floating point imprecision.
However this is really ineffective as half the time this code doesn't register for probably the same reason, and if I increase the 0.03f to a point where it never misses it becomes really noticeable that the cube isn't aligned with the grid anymore.
There has to be a proper solution to this and hopefully I've clarified the situation enough?
Any advice is appreciated.

You are moving your cube via
transform.Translate(direction * moveSpeed * Time.deltaTime);
which will never be exact an might overshoot your positions.
=> I would rather implement a coroutine for moving the cube exactly one field at a time, ensuring that after each iteration it fully aligns with the grid and run your checks once in that moment.
It doesn't even have to match exactly then, you only need to check if you are somewhere hitting a cube below you.
So something like e.g.
private Vector3Int direction = Vector3Int.left;
private IEnumerator MoveRoutine()
{
// depends on your needs if this runs just forever or certain steps
// or has some exit condition
while(true)
{
// calculate the next position
// optional round it to int => 1x1 grid ensured on arrival
// again depends a bit on your needs
var nextPosition = Vector3Int.RoundToInt(transform.position) + direction;
// move until reaching the target position
// Vector3 == Vector3 uses a precision of 1e-5
while(transform.position != nextPosition)
{
transform.position = Vector3.MoveTowards(transform.position, nextPosition, moveSpeed * Time.deltaTime);
yield return null;
}
// set target position in one frame just to be sure
transform.position = nextPosition;
// run your check here ONCE and adjust direction
}
}
start this routine only ONCE via
StartCoroutine(MoveRoutine());
or if you have certain exit conditions at least only run one routine at a time.
A Corouine is basically just a temporary Update routine with a little bit different writing => of course you could implement the same in Update as well if you prefer that
private Vector3Int direction = Vector3Int.left;
private Vector3 nextPosition;
private void Start()
{
nextPosition = transform.position;
}
private void Update()
{
if(transform.position != nextPosition)
{
transform.position = Vector3.MoveTowards(transform.position, nextPosition, moveSpeed * Time.deltaTime);
}
else
{
transform.position = nextPosition;
// run your check here ONCE and adjust direction
// then set next position
nextPosition = Vector3Int.RoundToInt(transform.position) + direction;
}
}
Then regarding the check you can have a simple raycast since you only run it in a specific moment:
if(Physics.Raycast(transform.position, Vector3.down, out var hit))
{
direction = Vector3Int.RountToInt(hit.transform.forward);
}
assuming of course your targets have colliders attached, your moved cube position (pivot) is above those colliders (assumed it from your image) and your targets forward actually points int the desired new diretcion

I would do it this way. First I would split the ability of certain objects to be "moving with certain speed" and "moving in a certain direction", this can be done with C# interfaces. Why? Because then your "arrow" cube could affect not only your current moving cube, but anything that implements the interfaces (maybe in the future you'll have some enemy cube, and it will also be affected by the arrow modifier).
IMovingSpeed.cs
public interface IMovementSpeed
{
float MovementSpeed{ get; set; }
}
IMovementDirection3D.cs
public interface IMovementDirection3D
{
Vector3 MovementDirection { get; set; }
}
Then you implement the logic of your cube that moves automatically in a certain direction. Put this component on your player cube.
public class MovingStraight: MonoBehaviour, IMovementSpeed, IMovementDirection3D
{
private float _movementSpeed;
Vector3 MovementSpeed
{
get { return _movementSpeed; }
set { _movementSpeed = value; }
}
private Vector3 _movementDirection;
Vector3 MovementDirection
{
get { return _movementDirection; }
set { _movementDirection= value; }
}
void Update()
{
// use MovementSpeed and MovementDirection to advance the object position
}
}
Now to implement how the arrow cube modifies other objects, I would attach a collision (trigger) component for both moving cube and the arrow cube.
In the component of the arrow cube, you can implement an action when something enters this trigger zone, in our case we check if this object "has direction that we can change", and if so, we change the direction, and make sure that the object will be aligned, by forcing the arrow cube's position and the other object's position to be the same on the grid.
public class DirectionModifier: MonoBehaviour
{
private Vector3 _newDirection;
private void OnTriggerEnter(Collider collider)
{
IMovementDirection3D objectWithDirection = collider as IMovementDirection3D ;
if (objectWithDirection !=null)
{
objectWithDirection.MovementDirection = _newDirection;
// to make sure the object will continue moving exactly
// from where the arrow cube is
collider.transform.position.x = transform.position.x;
collider.transform.position.y = transform.position.y;
}
}
}
If you made your trigger zones too large, however, then the moving cube will "jump" abruptly when it enters the arrow cube's trigger zone. You can fix it by either starting a coroutine as other answers suggested, or you could make the trigger zones pretty small, so that the jump is not noticeable (just make sure not to make them too small, or they may not intersect each other)
You could then similarly create many other modifying blocks, that would change speed or something

I think that it is enough for you to check if the X and Z coordinates are equal, since the movement occurs only along them
Example
if(_player.transfom.position.x == _gameSquare.transfom.position.x && _player.transfom.position.z == _gameSquare.transfom.position.z)
{
Debag.Log("Rotate!")
}

How to make a slingshot?

enter image description here
enter image description here
I made this slingshot with objects in Unity3D. I know im suppose to add components but I dont know exactly which ones. The two yellows would represent as my elastics. Keep in note i have a robot arm made on the side. My claw hand will grab the object holder and pull it back so it can shoot. I need help in
what component should i add to them to make them like rubberband or elastic
how attach them to my objectHolder
how to make it shoot
please help and be patient with me :( Any advice I would appreciate it. Thank you :)
private Animation anim;
Rigidbody rb;
void Start()
{
anim = gameObject.GetComponent<Animation>();
}
void Update()
{
//********************Open pincher ********************
if (Input.GetKey(KeyCode.X))
{
anim.Play("clawopen");
//rb.AddTorque(Vector3.up * speed);
}
//*******************Close pincher ********************
if (Input.GetKey(KeyCode.Y))
{
anim.Play("clawclose");
// rb.AddTorque(Vector3.down * speed);
}
//*******************if not both ********************
else
{
rb.angularVelocity = Vector3.zero;
}
}
}

There is no magic component that will achieve what you want. You should break it down into smaller chunks.
Start with the movement of the object holder. There are different ways to achieve this. If you want to manipulate it via mouse, you can write a script that makes the objectHolder follow mouse movement while a mouse button is pressed. Once you release the mouse button you can let the object holder smoothly go back to it's start position.
For the elastic parts, I would replace the objects with LineRenderers. But also here are different ways to achieve this.
Maybe this tutorial helps you.

attach a spring component to the dark orange round shape and set connectedAnchor to the position of where it should stretch from. You can play around with soeing and damoer to make it more or less stretchy.
I would reccomend a very high spring (spring should be about 100-1000) and mass (mass should be about 5-10) on this. The ball should have a mass of 1 or less.
You can set the Rigidbody.position to the claw's position (while it is closed) Then when it opens' it will release and launch.
For example SlingShot.cs (on the dark orange object.
[HideInInspector] public bool closedClaw = false;
[HideInInspector] public Vector3 clawPos;
Rigidbody rb;
void Start()
{
rb = GetComponent<Rigidbody>();
}
void Update()
{
if (closedClaw)
{
rb.positon = clawPos;
}
}
And then somewhere in the script that closes the claw
SlingShot ss;
GameObject slingShot;
void Start()
{
ss = slingShot.GetComponent<SlingShot>();
}
...
if (right claw.localEulerAngles.z /*or whatever axis it rotates on*/
> 90f /*or whatever threshHold*/)
{
ss.closedClaw = true;
}
else
{
ss.closedClaw = false;
}
ss.clawPos = rightClaw.transform.position +
leftClaw.transform.position;
ss.clawPos /= 2f;
All of this is untested and may have errors.
If this all works,I will come back later and do the stretchy yellow rubber bands.
Requested by comment Open closing arm
public float speed;
public Transform rightClaw;
public Transform leftClaw;
public Vector3 axis;
public Vector2 minMaxRotation;
void Update()
{
if (Input.GetKey(KeyCode.X))
{
Press(1);
}
if (Input.GetKey(KeyCode.Y))
{
Press(-1);
}
}
void Press(int open)
{
float r = rightClaw.transform.localEulerAngles * axis;
rightClaw.transform.localEulerAngles =
axis * Mathf.Clamp(r + speed * open, minMaxRotation.x, minMaxRotation.y);
float l = leftClaw.transform.localEulerAngles * axis;
leftClaw.transform.localEulerAngles =
axis * Mathf.Clamp(l - speed * open, 180f - minMaxRotation.x, 180f - minMaxRotation.y);
}

How to make camera relative movement

I'm learning unity and c#, and want to make my movement to be camera relative movement instead of world relative movement. How do I do that?
I'm learning unity and c#, my unity version is 2018.3.12f1. I would be happy for help.
just to let know, instead of moving the cam I'm rotating the player.
void Update()
{
float AxisY = Player.transform.eulerAngles.y;
/* Movement starts here */
Vector3 Movement = new Vector3 (Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
if (Input.GetKey(KeyCode.LeftShift) || Input.GetKey(KeyCode.RightShift)) { //running code
Player.transform.position += Movement * running_speed * Time.deltaTime;
} else {
Player.transform.position += Movement * speed * Time.deltaTime;
}
/*Movement ends here */
/* Rotation controller starts here */
Quaternion target = Quaternion.Euler(Player.transform.eulerAngles.x, Player.transform.eulerAngles.y, Player.transform.eulerAngles.z);
/*if (Player.transform.eulerAngles.x != 0 || Player.transform.eulerAngles.z != 0 || Player.transform.eulerAngles.y != 0) {
Player.transform.rotation = Quaternion.Euler(0,0,0);
}*/
if (Input.GetKey(KeyCode.E))
{
Debug.Log("E got pressed");
//float AxisYPositive = Player.transform.eulerAngles.y;
AxisY = AxisY+1;
Player.transform.rotation = Quaternion.Euler(0, AxisY, 0);
} else if (Input.GetKey(KeyCode.Q))
{
Debug.Log("Q got pressed");
//float AxisYNegetive = Player.transform.eulerAngles.y;
AxisY=AxisY-1;
Player.transform.rotation = Quaternion.Euler(0, AxisY, 0);
}
}
}
The player's movement is world relative, how to make the movement camera relative?

If you want to make the movements relative to the gameObject, call the method Transform.Rotate() on the transform of the gameObject you want to rotate rather than modifying its Quaternion directly. Just make sure the final argument is set to Space.Self.
if (Input.GetKey(KeyCode.E))
{
Debug.Log("E got pressed");
//float AxisYPositive = Player.transform.eulerAngles.y;
AxisY = AxisY+1;
Player.transform.Rotate(Quaternion.Euler(0, AxisY, 0), Space.Self);
}

In general you don't want to directly mess with objects transform.rotation, at least not unless you at least somewhat understand quaternions (I don't!).
I can see a few issues with your code, but the common thread seems to be that you don't really understand how transforms work. Specifically, you might want to look into World/Local space.
The usual way to control a player goes roughly like this:
void DoMovement(Transform player)
{
//If you move first your controls might feel 'drifty', especially at low FPS.
Turn(player);
Move(player);
}
void Turn(Transform player)
{
float yaw = Input.GetAxis("Yaw") * time.deltaTime; //Aka turn left/right
player.Rotate(0, yaw, 0, Space.Self);
// Space.Self is the default value, but I put it here for clarity.
//That means the player will rotate relative to themselves,
//...instead of relative to the world-axis, like in your code.
}
You didn't ask about movement, but as-is your character will always move relative to the world. The below should make it move relative to the camera.
Transform _cameraTransform; //Assumes this is set druing Start()
void Move(Transform player)
{
var forwardMove = _cameraTransform.Forward; //Get whatever direction is 'forward' for camera
forwardMove.Y = 0; //Don't want movement up and down.
forwardMove = forwardMove.normalized; //Normalize sets the 'power' of the vector to 1.
//If you set Y to 0 and don't normalize you'll go slower when camera looks down
//...than when camera is flat along the plane
player.position += forwardMove * Input.GetAxis("Vertical") * time.deltaTime;
//Here you could do the same for strafe/side to side movement.
//Would be same as above, but using the transform.right and Horizontal axis
}
Now, I'm making some assumptions here since you haven't specified what kind of game it is and what kind of controls you want. I'm assuming you have a character running around on a mostly flat plane (no aircraft/spaceship controls), and that the camera is attached to the player. This might not not actually be the case.
In any case I advice you to check out the tutorials, especially the Roll-a-Ball tutorial which I have found is good for beginners to get a grasp on basic players controls that are not just world-relative. The other tutorials, too, are pretty good if you think they're interesting.
Aside from the official Unity tuts a ton of decent to amazing tutorials out there, including video tutorials, so for something like this you could just search for <game type> tutorial and pick whatever seems good to you. While getting started I advice you to avoid the shortest videos, as you will likely benefit greatly from explanation that only fits in longer videos. Of course, that doesn't mean you should pick the longest videos either.

In case someone needs to move an object and don't care about colliders, you can use transform.Translate and assign to his second parameter relativeTo your camera (or any transform) to automatically calculate the translation relative to the object assigned.

(C#) Unity2D - Animation Fighting my Character's Movement?

I'd like to thank you in advance for helping me with this issue.
I have a player that consists of three part:
The body
The head
and the Arm
All three of these are individual sprites.
I have grouped them all under one Empty GameObject that I named "Player"
I have then added an animation on the "Player" GameObject that changes the Y position from 0 to 0.022, and then from 0.022 back to 0.
This create a nice little hover animation where the character bounces up and down.
The animation works perfectly fine!
However, I also have a script attached to the "Player" object, this script is called "PlayerController".
In PlayerController I change the player's x Position if they hold down A (for leftwards movement) or D (for rightwards movement).
protected bool facingRight = true;
float xPos = 0;
void Update()
{
if (Input.GetKey(KeyCode.D))
{
xPos += 0.01f;
if (!facingRight)
{
Flip();
}
}
else if (Input.GetKey(KeyCode.A))
{
xPos -= 0.01f;
if (facingRight)
{
Flip();
}
}
gameObject.transform.position = new Vector2(xPos, transform.position.y);
}
protected void Flip()
{
facingRight = !facingRight;
Vector3 theScale = transform.localScale;
theScale.x *= -1;
transform.localScale = theScale;
}
When I hold A or D, the character refuses to move. However he does flip correctly.
I personally think my animation is fighting the script, and that the animation has a higher priority than the script...?
Here's a video of me explaining my issue
(Not sure if videos are generally accepted in this community or not. If not, then I apologize)
If you guys could please help me understand what is happening and how to correct it I would be extremely grateful.
Thank you! :)

Solved the problem after hours of tinkering.
Turns out the solution was simple:
All I had to do was structure my player like this:
Player (Empty GameObject)
PlayerAssembly (Body, Head, and Arm's parent)
Body Parts (Body, Head, Arm)
and then put the script, rigidBody2D, and collider on "Player".
Then put the animator on "PlayerAssembly".

Object kept falling as opposed to shooting trajectory (Unity)

everyone! I am new to Unity and try to create a 2D arcade game by allowing my character to jump up at a trajectory motion to reach something then fall down. I use gravity scale equal to 1 and move_speed 1000 and rest_speed 500 but as soon as I hit space, the character just fell down instead of going up.
Also, walk.IsWalk is an int from Walking class(as soon as I hit right arrow, set IsWalk to 2 for example). My expected result would be as soon as we hold both space and right arrow key, the character should move upwards follow a curved motion. I dont know what is going on here, can anyone kindly point me to a direction? Thanks!
My code as follows:
using UnityEngine;
using System.Collections;
public class Jumping : MonoBehaviour
{
Rigidbody2D rb2D;
Animator anim;
Walking walk = new Walking();
public float move_speed;
public float rest_speed;
void Start()
{
rb2D = GetComponent<Rigidbody2D>();
anim = GetComponent<Animator>();
}
void FixedUpdate()
{
//float xmove = Input.GetAxis("Horizontal");
//float ymove = Input.GetAxis("Vertical");
//var curr = new Vector2(xmove, ymove);
if (Input.GetKey("space"))
{
anim.SetTrigger("JumpButtonPres");
rb2D.gravityScale = 1;
if (walk.isWalk == 2)
{
rb2D.AddForce(rb2D.position * move_speed);
}
else if (walk.isWalk == 1)
{
//rb2D.velocity += (Vector2.up * (-rb2D.velocity.x));
rb2D.AddForce(-rb2D.position * move_speed);
}
else
{
rb2D.AddForce(rb2D.position * rest_speed);
}
}
}
}
partial code for rigidbody2D.AddForce

It seems your problem is that whenever you are adding force to your rigidbody, you are multiplying it by the position where it's located, so by this i'm guessing your character is placed at a negative y component coordenate, and this is why rb2D.position * rest_speed will result on your playing falling. Change it for vector2.up * rest_speed and you should be fine.
Hope I was able to help.
Noé