How do I rewrite this older code with GetComponent instead?

Noob here. Trying to understand how to write the below code in a newer version of Unity. I need to access the rigidbody of the projectile, not of the object that the script is on:

GameObject projectile = (GameObject) Instantiate( bullet, myPos, rotation);
projectile.rigidbody2D.velocity = direction * speed;


I get the error:

Severity Code Description Project File Line Suppression State
Error CS0619 'GameObject.rigidbody2D' is obsolete: 'Property rigidbody2D has been deprecated. Use GetComponent<Rigidbody2D>() instead. (UnityUpgradable)' Game #1.CSharp C:\...\Gun.cs 42 Active

 

projectile.GetComponent<Rigidbody2D>().velocity

It does show you in the error message as well

 

Ah ok, I actually tried that but did not add the "()" at the end. I ended up putting it in two lines like so:

// Get the bullet's rigidbody
rb = projectile.GetComponent<Rigidbody2D>();

// Set the rigidbody's velocity
rb.velocity = direction * 1;

Any idea how to set the bullet's velocity so that it is not affected by the distance between my mouse and my player? The closer they are, the slower it shoots... which makes sense the way it's coded now. And also, how would I find the answer to this on my own?

 

Normalize your vector.

Code (csharp):

1.  
2. direction.normalized * 1f; // may want to increase this
3.  

 

Thanks! So now I should be able to access my ship's velocity and add that into the velocity somehow too, right? bullets start going slower than my ship if I'm moving in the same direction I'm firing.

 

Sure - just add your ship's velocity to the projectile's.

Code (csharp):

1.  
2. projectileRigidbody.velocity =  shipRigidbody.velocity + (direction.normalized * 1f);
3.  

 

Ah simpler than I thought thank You!

Btw, are there tutorials or classes that go over Unity's functions, particularly math based ones? I jist don't understand the math enough to know what I'm even looking for sometimes.

For instance, how the hell are velocities simply added together? Aren't they multiple values?

 

There's a reference for the functions here:
https://docs.unity3d.com/ScriptReference/Vector3.html

But you may also want to check out some general info on vector math, such as:
https://www.mathsisfun.com/algebra/vectors.html

 

There are a few articles in the docs that cover Vector arithmetic but you'd be better off finding a mathematics related site.

 

Yeah so I know to reference Vector3 on the unity site, but I don't think I'd ever even know about Vector3 unless a tutorial used it.

Secondly... Ok vectors. Now what? What else am I missing. I need something like a "math for game development" course or something.

Thirdly, now what about ALL functions, even non math ones? Am I expected to just dig through each one on the unity site to get a feel for them?

 

You dont use them all...
This stuff is usually on a need-to-know basis. You cant memorise every function...

 

Precisely. Keep watching tutorials and learning how different things work, and over time you'll get a grip on all the common knowledge you'll need. At least to google effectively.

Math for Game Developers:
https://www.youtube.com/playlist?list=PLW3Zl3wyJwWOpdhYedlD-yCB7WQoHf-My

 

The Scripting Learning Annex will cover pretty much everything you'll ever need.

 

So I got this to work with something like this

void Start () {
gunRB = GetComponentInParent<Rigidbody2D>();
playerRB = gunRB.GetComponentInParent<Rigidbody2D>();
}
...
bulletRB.velocity = playerRB.velocity + (direction.normalized * BulletSpeed);

However this didn't solve the problem like I thought it would. If I drive my ship forward and shoot, the bullets go way too fast. If I drive backwards while shooting forward, the bullets almost stand still.

Is there some kind of game design trick I'm missing here?

 

No - that's expected. If you throw a baseball 30 mph backwards out of a car moving 30 mph forwards, it just drops straight to the ground.

Maybe you want something more arcade-y and don't want to add the ship's velocity after all?