Create Script then add to RigidBody error

I'm creating a script in the project folder called doPhysics. I want to attach it to a Sphere gameObject during runtime from my main script worldsetup.js using addComponent.

It tries to compile itself ahead of time? But since it's not attached to a rigidbody yet it can't compile?

It says RigidBody is not a member of UnityEngine
How do I get past this?
Thanks,
Dan

Here is the script.


function FixedUpdate () {
if (this.gameObject.Rigidbody){
this.gameObject.Rigidbody.AddForce(Vector3(0,10,0));
}
}

 

Hint: Your code won't work if you manually add it either.

edit: off the top of my head:

Code (csharp):

1. if (rigidbody){
2.     rigidbody.AddForce(Vector3(0,10,0));
3. }

 

It works.
Why does that work.
what is rigidbody?
It is not Rigidbody so what's the difference?

I don't get it.
and I can't find the lowercase one in the manual.

Thanks,

Dan

 

All of the lowercase references are here:

http://unity3d.com/support/documentation/ScriptReference/Component.html

The lowercase "rigidbody" is a reference to the instance of a RigidBody component on the GameObject, if one exists.

Likewise, "transform" is a reference to the instance of a Transform component on the Game Object (which will always exist).

It's just a naming convention. Class names are done in CamelBack style, with the first letter uppercase, while variables generally start lowercase.

 

Rigidbody can be viewed as a type of component. Most common components can be attached as member variables... the lowercase rigidbody is the member variable for that.

Easier than writing GetComponent(Rigidbody).AddForce(Vector3(0,10,0));

edit: Matthew beat me to the reply...

 

If it helps you think about it, writing "rigidbody" is basically shorthand for writing GetComponent(Rigidbody).