how do you check for a Vector3 == null

Questions & Answers
1

hi , I'm pretty new to unity and Im having a few 'problems' converting my javascript code to unitycode. Ive seen that unity can check if a value is null or not (http://unity3d.com/support/documentation/ScriptReference/Object-operator_bool.html) but why can't Vector3 be checked for null with || like all other types ? Is there any short form for this or do I really have to write the if solution?

doesnt work:

var type:String;

var position:Vector3;

...

function (type:String,position:Vector3)

...

this.type = (type||"UNDEFINED");
this.position = (position||Vector3(0,0,0));

...

doesnt work either:

var type:String;

var position:Vector3;

... 

function (type:String,position:Vector3)

...

this.type = (type||"UNDEFINED");
this.position = Vector3(0,0,0);
if (position) this.position = position;

...

really as:

var type:String;

var position:Vector3;

... 

function (type:String,position:Vector3)

...

 this.type = (type||"UNDEFINED");
 this.position = Vector3(0,0,0);
 if (position==null) this.position = position;

...

Ent

2

A Vector3 is a struct and therefore can never be null. They start out as `Vector3(0, 0, 0)`. If you try to compare a struct to null (an object type), you will get compilation errors.

4

Since you're using Unityscript (which really isn't Javascript, but Unity's version of it), then this answer doesn't really apply. I'm posting it mainly for information.

However, in C#/.NET/Mono, it is possible to make some types Nullable. For instance, this code works (in C#):

void Start () {
Vector3? foo = null;
//foo = Vector3.zero; // would set non-null, but zeroed.
Vector3 bar = foo.Value; // foo is new type, have to get Value.
if (foo == null)
    Debug.Log("foo is null");
else
    Debug.Log("foo is non-null");
}

Note the Vector3? with a ?, which is what makes the type nullable.

Of course, if you write some of your scripts in JS, and some in C#, then you run into compilation-order issues, but it would work. Making a type Nullable also adds slightly more syntax, if you assign it to a standard type (you have to access the Value property).

3

Sorry but it cant be null, just make the co-ordinates 0,0,0 if you dont mind me asking, what were you trying to do?