Raycast problems

I am trying to raycast from an object but if the object has a sphere collider the ray seem to hit the sphere collider (ie if doesn't go beyond the object), but if I change the collider to a mesh collider then the ray seems to intersect objects beyond the object the script is attached to.

Is this correct ie that you can only have a mesh collider?

thanks,
Richard.

 

My situation is a little more complex. I have several bots all casting rays to sense their environment. So, I guess in each Update call I have to switch the current bot to a different layer and set the layermask to the other layers. I tried the following sort of thing:

Code (csharp):

1.    
2. private   LayerMask feelRays = 9;  
3. private   LayerMask ignoreRays = 8;
4. private   LayerMask rayLayer;
5.  
6. void Update () {
7.     RaycastHit hit  ;
8.     // put the caster in the ignore layer
9.      layer = ignoreRays;
10.      // intersect with all other layers      
11.      rayLayer = ~ignoreRays;
12.      if (Physics.Raycast (transform.position, Vector3.forward, out hit,rayLayer)) {
13.             distanceToHit = hit.distance;
14.             print("The ray hit something");
15.         }
16.       layer = feelRays;
17.     }    
18.  

however, I get the compile error "The name `layer' could not be found in `myScript'". I also tried creating a public GameObject variable (called "me") so that I could drag the object the script was attached to on to it and use "me.layer = ignoreRays;". The latter script compiled fine, but Unity immediately crashed when I started "Play"
thanks,
Richard.

 

I really can't get this to work - even if I try with just one player and maunally assign the layers - keeps crashing Will post report shorty.

I'll switch to js to see if I can get it to work (but really need to use C# beacuse of th "switch" and "for" problems in js).


Ignore self would definitely be a good option

thanks,
richard.

 

Aren't If's a bit slower then a switch statement? I seem to remember a problem like that in my uDG entry last year. I was doing a bunch of if's that I was able to turn into some switches and it made it run a lot faster...

 

Originally I couldn't get "for" to work since I was using <=, but now realise the problem is the "=" bit and should just stick with "<". I am about to write a fare amout of code and nervous about starting out with js in case there are other problems.

Richard.

PS Just fixing up the project for the bug submission now..

 

Ok - the bug wasn't listed in the release report so I assumed it was still broken - sorry - should have tested it.

Richard.

 

Not a problem - I know how difficult it is to track all these things - been there myself

Richard.

 

Using your Wiki js script and it works fine! I am happy (for the moment)

thanks,
Richard.

 

It appears the "for" bug is still there:

Code (csharp):

1. for(var i=1;i< numEyes;i++) {
2.        
3.         if (Physics.Raycast (transform.position, lookDir, hit, Mathf.Infinity, layerMask)){
4.             Debug.DrawRay (transform.position, lookDir * hit.distance, Color.yellow);
5.             gameObject.layer = 0;
6.          } else {
7.                 Debug.DrawRay (transform.position, lookDir *1000, Color.red);
8.          }
9.      }  

does not generate an error, but (replacing "<" with "<="):

Code (csharp):

1.  
2. for(var i=1;i<= numEyes;i++) {
3.        
4.         if (Physics.Raycast (transform.position, lookDir, hit, Mathf.Infinity, layerMask)){
5.             Debug.DrawRay (transform.position, lookDir * hit.distance, Color.yellow);
6.             gameObject.layer = 0;
7.          } else {
8.                 Debug.DrawRay (transform.position, lookDir *1000, Color.red);
9.          }
10.      }  

does generate an error :-(

Richard.

 

Going back to the C# -( ). I don't really understand the "out" thingy in the raycast declaration:

Code (csharp):

1. bool Raycast (Vector3 origin, Vector3 direction, out RaycastHit hitInfo, float distance = Mathf.Infinity, int layers = kDefaultRaycastLayers)

Is is some sort of constructor? because I notice that there doesn't appear to be a constructor for the RaycastHit class ie. variations on

Code (csharp):

1.  RaycastHit myInfoBlock = new RaycastHit(???)

all seem to generate a compile error.

thanks,
Richard.

 

Sorry - just rechecked with my C# book - "out" says the variable is passed ny reference - so I guess a constructor for RaycastHit isn't needed and the Raycast method just keeps the RaycastHit memory block around for the script to query?

thanks,
Richard.

 

Sorry - anouther problem. I think this must be a bug (or I am missing something): I am raycrasting from an empty object (ie a transform) and rotating it after each cast. If the raycast in the direction of a rigidbody with a capsule collider it correctly registers a hit, however, it also registers a hit with the same rigidbody if it casts in a direction pointing 180 degrees AWAY from the rigidbody.

If however, I replace the capsule collider with a mesh collider then the 180 raycast doesn't register (ie the raycasting works correctly).

Richard.

 

Uuum I don't think so - I'll post a screenshot illustrating the effect... after I have downloaded rc1

thanks,
Richard.

 

The movie shows a transform-only object (ie no mesh at all) which has a raycasting script which uses Physics.Raycast and Debug.DrawRay. The drawn ray is one of two colours - red if it hits an object with *no* rigidbody and yellow otherwise. As you can see the raycasting object is also rotating as it casts the rays. Now, in the screen capture below I have tried to illustrate that the raycaster is claiming (because it turns yellow) that there is a rigidbody at positon "A", when in fact the is NO object there at all. Notice that the "ghost" object at "A" is 180 degrees from the real rigidbody. This happens whereever I place the real rigid body - the ghost object is always 180 around.

Now, the rigidbody that gives rise to the ghost object has a capsule collider, if, however, I replace the capsule collider with a mesh collider the problem goes away ie all works fine.

Am I doing some silly?
many thanks,
Richard.

 

I found the problem with the C# script and the crashing. My fault entirely - in the line

Code (csharp):

1. rayLayer = ~ignoreRays;

the "~" is a descructor, not a negation Apologies for wasting your time.

Richard.

 

The following script when attached to an object will crash Unity:

Code (csharp):

1. using UnityEngine;
2. using System.Collections;
3.  
4. public class crasher : MonoBehaviour {
5.    
6. private  LayerMask ouch = 0;
7. private  LayerMask eep;
8.  
9.   void Update () {
10.      eep = ~ouch;
11.   }
12. }
13.