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Using 2D raycast in perspective not returning collision

I'm using 2D colliers in my game, and I want to use a perspective camera also. I have a raycast working in orthographic that draws a line from the player to a clicked point. It, of course, breaks when I change the camera to perspective.
I've been trying to get it to work in 2D, but without success.
I'm trying to cast a ray from the player character in the direction of the mouse position on screen, and returning the first hit 2D collider.
This is what I have so far which doesn't work. I appreciate some help.
void RaycastToCollider()
{
Ray ray = new Ray();
ray.direction = Camera.main.ScreenToViewportPoint(Input.mousePosition) - transform.position;
ray.origin = transform.position;
RaycastHit2D hit = Physics2D.GetRayIntersection(ray, Mathf.Infinity);
if (hit.collider != null)
{
Debug.DrawLine(ray.origin, hit.point);
}
}

Why ScreenToViewportPoint? This only returns a pixel position (e.g. 356 x 847) into normalized viewport coordinates that move in range 0 to 1 (e.g. 0,07 * 0,26)
Since it is purely about the direction you want to get you could go the other way round via the screen.
Also not sure but I would simply use a Raycast instead of GetRayIntersection
void RaycastToCollider()
{
// already is in screen space anyway
var mouseScreenPos = Input.mousePosition;
var transformPos = transform.position;
var transformScreenPos = Camera.main.WorldToScreenPoint(transformPos);
var direction = (Vector2)mouseScreenPos - (Vector2)transformScreenPos;
var ray = new Ray(transformPos, direction);
var hit = Physics2D.Raycast(transformPos, direction, Mathf.Infinity);
if (hit.collider != null)
{
Debug.DrawLine(ray.origin, hit.point);
}
}

Unity3D - Using Raycasting to detect Game Objects. Top-down view

I'm making a top down space resource-gathering game, with 3D models.
I'm trying to cast a ray towards my mouse position, to detect collisions with the objects in my game,
for my little spaceship to know which direction to head to find resources.
The resources are in the form of asteroids the player has to break to gather.
In the code, I use the "center" vector to find the middle of the screen/player position, as the camera follows the player around. All movement happens along the X,Y axis. center.Z is set to 15 simply to counteract the -15Z position of the main camera in worldspace.
So far, the code "works" to the extent that it can detect a hit, but the ray doesn't travel in the direction of the mouse. I have to hold it way off for it to hit, and it's difficult to replicate, to the point where it almost seems random. Might the ray not be able to make sense of the mouse position?
In case I've worded myself poorly, this search ability is not meant to break the asteroid, simply locate it. The breaking ability is a separate script.
Code:
public class AbilitySearch : MonoBehaviour
{
Vector3 center;
Vector3 mousePos;
Vector3 direction;
private float range = 100f;
void Update()
{
center = Camera.main.ViewportToWorldPoint(new Vector3(0.5f, 0.5f, 15.0f));
mousePos = Input.mousePosition;
direction = mousePos - transform.position;
if (Input.GetMouseButton(1))
{
Search();
}
}
void Search()
{
RaycastHit hit;
if (Physics.Raycast(center, direction, out hit, range))
{
Debug.Log("You hit " + hit.transform.name);
}
}
}
Thanks in advance

When using Input.mousePosition the position is a pixel coordinate on your screen, so if your mouse was in the bottom left corner of your screen it would be 0,0. This causes the direction to be inaccurate. When what you need is to use the game space coordinates, which is done by using Camera.ScreenToWorldPoint(Input.mousePosition), as an example.
This solution allows you to click on a gameObject (provided it has a collider attached), move the current gameObject towards the clicked object, as well as gather an array of possible gameObjects (RaycastHit[s]) in the direction of the clicked one.
Vector3 destination;
RaycastHit[] possibleTargets;
bool isTravelling;
float searchDistance = 5f;
private void Update()
{
//If right mouse button has been pressed down
if (Input.GetMouseButtonDown(1))
{
RaycastHit hit;
Ray ray = Camera.main.ScreenPointToRay(Input.mousePosition);
if (Physics.Raycast(ray, out hit)) //If ray collides with something
{
Search(hit);
}
}
//If going to destination
if (isTravelling)
{
float step = 2f * Time.deltaTime;
transform.position = Vector3.MoveTowards(transform.position, destination, step);
//If approx arrived
if (Vector3.Distance(transform.position, destination) < 0.1f)
{
isTravelling = false; //Stop moving to destination
Debug.Log("You've arrived");
}
}
}
private void Search(RaycastHit _hit)
{
//Normalise directional vectors, so (if needed) they can be multipled as expected
Vector3 direction = (_hit.point - transform.position).Normalized();
RaycastHit secondHit;
//Grab objects in direction of clicked object (including the one clicked)
possibleTargets = Physics.RaycastAll(transform.position, direction, searchDistance);
Debug.Log($"There are {possibleTargets.Length} possible targets ahead");
Debug.Log($"You hit {_hit.transform.name}");
//Set destination, and set to move
destination = _hit.point;
isTravelling = true;
}

You used the ViewportToWorldPoint method, which expects normalized viewport coordinates in range 0 to 1, but you supplied what seems to me as world coordinates of your camera as its parameter.
You only need to cast a ray from camera to mouse pointer world position (see first line of code in method FindAsteroid) to check for collision with asteroid. The returned RaycastHit provides you with information about the collision - hit position, gameobject, collider - which you can use for other game logic, e.g. shooting a projectile from spaceship to asteroid hit point.
I edited your class and included a screenshot from my simple scene below, which shows the two different "rays":
The yellow ray goes from camera to asteroid hit point
The magenta ray goes from spaceship position to asteroid hit point.
I would also recommend filtering the raycast to affect only specific colliders -
see LayerMask (section Casting Rays Selectively)
public class AbilitySearch : MonoBehaviour
{
private float range = 100f;
private Camera mainCam;
private void Awake()
{
// TIP: Save reference to main camera - avoid internal FindGameObjectWithTag call
mainCam = Camera.main;
}
private void Update()
{
if (Input.GetMouseButton(1))
{
if (FindAsteroid(out var asteroidHit))
{
// Draw a line from spaceship to asteroid hit position
Debug.DrawLine(transform.position, asteroidHit.point, Color.magenta, Time.deltaTime);
Debug.Log($"You hit {asteroidHit.transform.name}");
}
}
}
private bool FindAsteroid(out RaycastHit hit)
{
// Create a ray going from camera position to mouse position in world space
var ray = mainCam.ScreenPointToRay(Input.mousePosition);
if (Physics.Raycast(ray, out hit, range))
{
// Draw a line from camera to world mouse position
Debug.DrawLine(ray.origin, hit.point, Color.yellow, Time.deltaTime);
// An asteroid was found
return true;
}
// An asteroid was NOT found
return false;
}
}
Sample spaceship scene

How do I drag objects on the screen using `OnMouseDrag`?

Tried doing 2D and 3D. I want the player to click and drag objects to stack them. I tried copying and pasting code from a video and it still didn't work.
UPDATE! Now it kinda works but it teleports the object far off the screen. I want the player to be able to smoothly click and drag the object.
The code as of now:
using UnityEngine;
using System.Collections;
public class DragObject : MonoBehaviour
{
private float deltax, deltay;
private void OnMouseDown()
{
deltax = 1f;//Camera.main.ScreenToWorldPoint(Input.mousePosition).x - transform.position.x;
deltay = 1f; //Camera.main.ScreenToWorldPoint(Input.mousePosition).y - transform.position.y;
}
private void OnMouseDrag()
{
Vector2 currentTouchPos = Camera.main.ScreenToWorldPoint(Input.mousePosition);
transform.position = new Vector2((Input.mousePosition).x - deltax, (Input.mousePosition.y) - deltay);
}
}

It's not clear at all what exact problem is for you, you obviously need to give more info and describe your issue better. But I'll try to help as I can.
To get mouse position you need to use:
Input.mousePosition
If you need mouse position in 2d coordinates you can use this:
Vector2 currentTouchPos = mainCamera.ScreenToWorldPoint(Input.mousePosition);

This method works regardless of your camera type or how the camera moves between frames
First, when the object is first clicked, get the plane at the object's position perpendicular to the direction of the camera:
Plane dragPlane = new Plane(Camera.main.transform.forward, transform.position);
Then, get the ray coming out of the camera from where the mouse is:
Ray camRay = Camera.main.ScreenPointToRay(Input.mousePosition);
Find out where that ray intersects using Plane.Raycast:
float enter = 0.0f;
if (dragPlane.Raycast(camRay, out enter))
{
Vector3 fingerPosition = camRay.GetPoint(enter);
This gives you a position in world space, which is where you can consider the finger to currently be at. Just put the object there:
transform.position = fingerPosition;
Altogether it might look like this:
void OnMouseDrag()
{
Plane dragPlane = new Plane(Camera.main.transform.forward, transform.position);
Ray camRay = Camera.main.ScreenPointToRay(Input.mousePosition);
float enter = 0.0f;
if (dragPlane.Raycast(camRay, out enter))
{
Vector3 fingerPosition = camRay.GetPoint(enter);
transform.position = fingerPosition;
}
}
No OnMouseDown necessary.
An alternative is to keep track of how fingerPosition changes over time, and Translate the transform based on that. Keeping as much math as possible in world units makes it easy:
Vector3 prevFingerPosition = Vector3.zero;
// Same code as before but we use it in different places so it goes in its own method.
// If the Raycast fails, return a decent guess.
private Vector3 GetMouseOnPositionInWorldSpace()
{
Plane dragPlane = new Plane(Camera.main.transform.forward, transform.position);
Ray camRay = Camera.main.ScreenPointToRay(Input.mousePosition);
float enter = 0.0f;
if (dragPlane.Raycast(camRay, out enter))
{
return camRay.GetPoint(enter);
}
return prevFingerPosition;
}
void OnMouseDown()
{
prevFingerPosition = GetMouseOnPositionInWorldSpace();
}
void OnMouseDrag()
{
Vector3 fingerPosition = GetMouseOnPositionInWorldSpace();
transform.Translate(fingerPosition-prevFingerPosition);
prevFingerPosition = fingerPosition;
}
There is an issue behind using OnMouseDrag to handle dragging objects around is that if the cursor moves too quickly, it can move off the object in the span of a single frame, and it will "drop" the object.
If that's not desirable, you might want to set a bool to be true in OnMouseDown that remembers that the object was clicked and a move the logic out of OnMouseDrag and into Update where it can do its thing if that bool is true. And when the mouse is released, set that bool back to false.

How can I launch the ball based on the position of the touch on the screen?

So I am trying to make a game where you are rquired to set the angle and speed of a ball that has to bounce on specific platforms in order to get to the destination.
Now, how do I find the direction from where the finger touches, to the ball, in order to make it move "away from the finger".
I have tried to use the subtraction of vectors in order to get the direction but It does not work since the vectors are relative to the world origin...it always gives me a wrong direction...
How do I solve this problem, I need a direction vector relative to touch and player(the ball), not to world, so I can launch the ball.
You will see that in the next picture I am simulating a touch with the mouse arrow(let say the mouse arrow is the finger of the player.I want to launch the ball based on the distance and position of the finger relative to the ball. It works well in the code BUT ONLY if the ball is placed on the origin of the scene, so i think it's a mathematical problem with vectors that I don't know how to resolve...
Below is the code that I have by now. It is attached to the ball's gameobject:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerController : MonoBehaviour {
[SerializeField]
Camera playerCamera;
Rigidbody rb;
Vector3 touchPostion;
private void Awake()
{
rb = GetComponent<Rigidbody>();
}
private void FixedUpdate()
{
if (Input.GetMouseButton(0))
{
LounchPlayer();
}
}
void LounchPlayer()
{
Vector2 mousePos = Input.mousePosition;
touchPostion = (transform.position - playerCamera.ScreenToWorldPoint(
new Vector3(mousePos.x,
mousePos.y,
playerCamera.transform.position.z))).normalized;
rb.AddForce(touchPostion.normalized, ForceMode.Impulse);
}
}

When finding your touch position, the z component of ScreenToWorldPoint's parameter should be an appropriate distance along the camera's forward vector, definitely not the camera's world z position. playerCamera.nearClipPlane is appropriate here, but really any small constant (such as 0) would suffice.
Also, there is no need to normalize the launch direction twice.
Vector2 mousePos = Input.mousePosition;
touchPostion = (transform.position - playerCamera.ScreenToWorldPoint(
new Vector3(
mousePos.x,
mousePos.y,
playerCamera.nearClipPlane))
).normalized; // This isn't a position vector; it's a direction vector.
// The var name "touchPosition" is misleading and should be changed.
float launchMagnitude = 1f; // change this to adjust the power of the launch
rb.AddForce(touchPostion * launchMagnitude , ForceMode.Impulse);

Unity C# camera zoom script

So before I explain my problem. I will first tell what I am really doing.
I am working on a click to move/zoom camera script. There are 3 planes in front of my Main Camera. Now what I am doing is, creating a script which says " The camera will zoom on the plane which gets clicked. I made several attempts to come up with a working script but it didn't worked well. Every time I come across new bugs , errors and what not. :|
I got frustrated and deleted the buggy script. Now I want to start from scratch. I am doing it in C#
Since I am not a professional, Can anyone explain me in detail to get it done?
I am confused how to deal with the planes I placed. I want to know what is missing in my script.
Here is a screenshot of how I placed those planes.
Edit. - I managed to work on it. Now I need advice, how to target the planes I placed in front of the camera.
using UnityEngine;
using System.Collections;
public class CameraZoom : MonoBehaviour
{
public int zoomLevelSelected = 0;
public float[] ZoomLevels = new float[] { 60, 40, 20 };
void Update()
{
int zoomChange = 0;
if (Input.GetMouseButtonDown(0)) { zoomChange = +1; } // back
else if (Input.GetMouseButtonDown(1)) { zoomChange = -1; } // forward
if (zoomChange != 0)
{
zoomLevelSelected = Mathf.Clamp(zoomLevelSelected + zoomChange, 0, ZoomLevels.Length - 1);
camera.fieldOfView = ZoomLevels[zoomLevelSelected];
}
}
}

Heck with it, here is one way to create a click zoom. The gist is that you create a ray from your camera in to the scene through the mouse cursor. When that ray intersects an object create a second ray from the point of intersection back out along the intersecting face's normal.
void Update () {
if(Input.GetMouseButtonDown(0)){
// get ray from camera in to scene at the mouse position
Ray ray = Camera.mainCamera.ScreenPointToRay(Input.mousePosition);
RaycastHit hit;
// hardcoded "zoom" distance.
float zoomDist = 15.0f;
// Raycast from camera to mouse cursor, if object hit, zoom.
if (Physics.Raycast(ray,out hit,Mathf.Infinity)){
// Create a second ray from the hit object back out, zoom the camera along this ray.
Ray r = new Ray(hit.point,hit.normal);
Camera.mainCamera.transform.position = r.GetPoint(zoomDist);
}
}
}
Things to keep in mind:
Physics.Raycast, as written, will return true for any GameObject with a collider. Use layers if you only want to zoom when selecting specific GameObjects.
The camera won't directly center on the GameObject you click. I use the exact point of intersection to create the position where the camera will zoom to.
zoomDist is the distance away from the object.
This code only works with perspective cameras, if you use orthographic you'll need to modify the size value of the camera to zoom.

The problem with your script is that your var int zoomChange is getting set to zero every frame so move that variable to class level.
using UnityEngine;
using System.Collections;
public class CameraZoom : MonoBehaviour
{
public int zoomLevelSelected = 0;
public float[] ZoomLevels = new float[] { 60, 40, 20 };
int zoomChange = 0; //<<<<<<<<<<<<<
void Update()
{
if (Input.GetMouseButtonDown(0)) { zoomChange = +1; } // back
else if (Input.GetMouseButtonDown(1)) { zoomChange = -1; } // forward
if (zoomChange != 0)
{
zoomLevelSelected = Mathf.Clamp(zoomLevelSelected + zoomChange, 0, ZoomLevels.Length - 1);
camera.fieldOfView = ZoomLevels[zoomLevelSelected];
}
}
}