Move an object from point A to B?

Unity Engine
1

Hello, I am making a 2D shooter and I have a question about firing a bullet:
When I click the mouse, I want to move an object outwards from point A in the direction of point B at a set velocity. I want point B to be wherever the mouse is clicked on the screen, how can that be done.

I have tried this;

var projectile : Rigidbody; 
var speed = 2; 
function Update() 
{ 
 if( Input.GetButtonDown( "Fire1" ) ) 

 { 
  var instantiatedProjectile : Rigidbody = Instantiate( 
   projectile, transform.position, transform.rotation ); 

  instantiatedProjectile.velocity = 
   transform.TransformDirection
   (Event.mousePosition); 
 } 

      }

But using this just makes the object move in a weird direction (sometimes even at the camera) I have also tried to work in “Input.mousePosition” but I cannot get that to work. Does anyone have any code that would fix my script(or another script that would accomplish what I want to do)? Thank you.

2

I haven’t worked with mouse position before, but my guess, is that the mouseposition is relative to the camera, and not your character.

3

Mouse position is the pixel coordinate of the mouse on the screen… i.e. useless for this.

Here is a script I wrote that is similar to what you wanted.

The important bit is that we get the mouse point as a ray (point in space with direction) - and then we have to figure out where this is in real space - either by arbitrarily picking a point (50 units in-front of me), or by using some other criteria (collides with game-object).

var targetRange : float = 50.0;
var turnSpeed : float = 6.0;
var _parent : Transform;

function LateUpdate(){

var ray : Ray = Camera.main.ScreenPointToRay(Vector3(Input.mousePosition.x,Input.mousePosition.y,0));
var rayHit : RaycastHit;
var rotateTo : Quaternion;

Debug.DrawRay(ray.origin, ray.direction * targetRange, Color.yellow);

if(Physics.Raycast(ray, rayHit, targetRange)  rayHit.transform != _parent ){
      rotateTo = Quaternion.LookRotation(rayHit.transform.position - transform.position, transform.up);
   }else{
      rotateTo = Quaternion.LookRotation(ray.GetPoint(targetRange) - transform.position, transform.up);
}
transform.rotation = Quaternion.Slerp(transform.rotation, rotateTo, Time.deltaTime * turnSpeed);
}
4

Thank you for your help, but I am still somewhat lost. If I understand your script correctly, it is supposed to take wherever I click on the screen and draw a line from parent object to that point. I added the script to the scenes camera and nothing noticeable happened (I had gizmos turned on in unity). What am I doing wrong?

5

I forgot to mention - that’s a turret script - so it aims (with the rotateTo) what ever its applied to to the point in space.

That line only appears within the scene window, and only when it is running :frowning:

I now rewrote it to show off it’s full functionality far more clearly - just open the project and run it with Gizmo’s on as you did before.

Being a 2D shooter you may get off easily. If you’ve got it so that ‘z’ is depth, then all you should need to do is go:

//untested

target : Vector3;

function Update(){

  //get the ray
   var ray : Ray = Camera.main.ScreenPointToRay(Vector3(Input.mousePosition.x,Input.mousePosition.y,0));
  //Since there is no 3d  angle - the x and y cords are going to be the same no matter how far you shoot it - so why bother?
   target = ray.origin;
//get rid of the pesky z (assumes that your game runs on the z = 0 plane thingy).
   target.z = 0;
/// if you wanted, you could get rid of the 'ray' altogether, but it makes for nice reading/demonstration.
}

429499–14885–$mouseAim.zip (43.6 KB)