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Laser Beam using Raycasting & Line Renderer
Hello,
I am trying to us Line-Renderer to be able to see my Space-Ship shoot lasers, but when i do render the line it goes from the laser origin cube to the ship instead of the the actual target?
Raycast Code:
var laserOriginOne : GameObject;
var hitOne : RaycastHit;
function Update () {
if(Input.GetButton("Fire Laser")){
if(Physics.Raycast(laserOriginOne.transform.position, Vector3.forward)){
laserOriginOne.GetComponent(ShipFire).FireLasers(hitOne);
Debug.Log(hitOne.transform);
}
}
}
'FireLasers()' Code:
var lineOne : LineRenderer;
function Start() {
lineOne = GetComponent(LineRenderer);
lineOne.enabled = false;
lineOne.SetVertexCount(2);
lineOne.SetWidth(0.1f, 0.25f);
}
function FireLasers(hitOne : RaycastHit){
lineOne.enabled = true;
lineOne.SetPosition(0, transform.position);
lineOne.SetPosition(1, hitOne.point);
}
Like i said i don't know why the laser goes from the 'laserOriginOne' to my 'ship'?
I have tried a few thing such as moving my ship away from the laserOrigin blocks.
Thanks for any help!
Answer by Owen-Reynolds · Oct 14, 2013 at 04:03 PM
You're never setting the hitOne
variable, so it stays all 0's. That debug line should be showing you that. Change the raycast command so it does, by adding hitOne
at the end:
Physics.Raycast(laserOriginOne.transform.position, Vector3.forward, hitOne))
Take a look at the script reference for Raycasts. It's a little tricky -- hitOne is an output parameter, which means it starts empty (like you have it) and is filled in by the ray cast. If you don't send it, the ray cast doesn't write the hit position anywhere.
There's also probably a problem with using Vector3.forward
for the direction. That will always shoot the laser due North. Just in general, you might want to browse through a bunch of other raycast examples here (shooting is a popular topic.) Raycasts use some tricky programming stuff.
Thanks that worked, as for the Vector3.forward, i changed that to be a variable called 'fwd' which is set with this:
var fwd = laserOriginOne.transform.TransformDirection(Vector3.forward);
A shortcut for "my forward" is transform.forward
(no TransformDirection needed.) It's pretty common in snippets of Unity code. TransformDirection can be saved for heavy-duty rotational math.
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