velocity of char.controller

Unity Engine
1

Hi,

I am fiddling with my character controller.
When grounded: take vector x,y,z

When not grounded (e.g jumping and falling) it should only take the X and Z.
This way, the character respond to the joystick while jumping too.
…But I need to retrieve the Y vector as well

E.g:

moveDirection = new Vector3(Input.GetAxis("Horizontal"), CURRENT_Y_SPEED_HERE, Input.GetAxis("Vertical"));

If the player is falling down very hard, the current Y would be -20 or something, so how do I capture this “y velocity property”?

full code:

var speed = 30.0;
var gravity = 1.0;
var jumpSpeed = 8.0;

private var moveDirection = Vector3.zero;
private var grounded : boolean = false;
private var difference : float = 0.0;

private var lastPosition = Vector3.zero;
private var thisPosition = Vector3.zero;

// -----------------------------------------------------------------------------------------


function Update () {
	thisPosition = transform.position;

	if (!grounded) {
		// THIS IS THE CODE THAT DOESNT WORK YET
		moveDirection.x = Input.GetAxis("Horizontal");
		moveDirection.z = Input.GetAxis("Vertical");
		MD = Camera.mainCamera.transform.TransformDirection(moveDirection);	
		moveDirection.x = MD.x *= speed;
		moveDirection.z = MD.z *= speed;

	}
	else if (grounded) {
		// THIS WORKS FINE
		moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));      
		moveDirection = Camera.mainCamera.transform.TransformDirection(moveDirection);		
		moveDirection *= speed;
		moveDirection.y = 0;


		if (Input.GetButton ("Jump")) {
			moveDirection.y = jumpSpeed;
		}
	}

	// hier eventuele code voor jumpen
	moveDirection.y -= gravity * Time.deltaTime;

	// Move the controller	
	var controller : CharacterController = GetComponent(CharacterController);
	var flags = controller.Move(moveDirection * Time.deltaTime); // verplaats de controller, return flag waarden voor collision detection
	grounded = (flags  CollisionFlags.CollidedBelow) != 0;

	lastPosition = transform.position;
}

Thank you.

2

not sure if this is valid javascript syntax:

moveDirection.x = MD.x *= speed;

have you tried this:

moveDirection.x = MD.x * speed;

3

Hi Joachim,

Thanks.
Indeed that is invalid syntax. :slight_smile: It didn’t change the behaviour though, so I guess Unity seems to handle it well.
What I basicly want to do is exactly the same code for grounded and !grounded, but not use 0 for the Y-ax. In that situation I want the current Y velocity of the character and pass it to the moveDirection vector.

If I do use 0 for the Y-ax, the character will not jump because a soon as he is airborne, he wont jump any further because of the moveDirection Y = 0.

E.g (pseudo code):

// NOT GROUNDED (IN AIR, JUMPING OR FALLING DOWN):
moveDirection = new Vector3(Input.GetAxis("Horizontal"), CURRENT Y VELOCITY, Input.GetAxis("Vertical"));      

// GROUNDED (WALKING):
moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));

I tried to use (thisPosition.y - lastPosition.y) to get the current velocity, but it causes the character to eject to the moon :slight_smile:

4 
// THIS IS THE CODE THAT DOESNT WORK YET 
  var MD = Vector3 (Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
 MD = Camera.mainCamera.transform.TransformDirection(moveDirection);              moveDirection.x = MD.x * speed; 
 moveDirection.z = MD.z * speed;

Try this. (This doesn’t maintain the y velocity when calculating MD, which is what you want)

Apart from that i cant really see what is wrong with the script without a running example.

5

Hi Joachim,

Thanks for your patience. I have implemented your code.
This is the actual demo (but be warned, it looks totally chaotic):
http://www.stickystudios.com/etc/har.html

I am not sure what is wrong with this code, it looks okay .

var speed = 30.0;
var gravity = 1.0;
var jumpSpeed = 8.0;

private var moveDirection = Vector3.zero;
private var grounded : boolean = false;
private var difference : float = 0.0;


// -----------------------------------------------------------------------------------------


function Update () {

	if (grounded) {
		// THIS WORKS FINE
		moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));      
		moveDirection = Camera.mainCamera.transform.TransformDirection(moveDirection);		
		moveDirection *= speed;
		moveDirection.y = 0;

		if (Input.GetButton ("Jump")) {
			moveDirection.y = jumpSpeed;
		}
	}

	else if (!grounded) {
		// THIS IS THE CODE THAT DOESNT WORK YET
		 var MD = Vector3 (Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical")); 
		 MD = Camera.mainCamera.transform.TransformDirection(MD);
		 // feed x and z to the original moveDirection vector, but leave Y alone.
		 moveDirection.x = MD.x * speed; 
		 moveDirection.z = MD.z * speed;
		}


	// perform gravity
	moveDirection.y -= gravity * Time.deltaTime;

	
	var controller : CharacterController = GetComponent(CharacterController);
	// Move the controller	
	var flags = controller.Move(moveDirection * Time.deltaTime); // verplaats de controller, return flag waarden voor collision detection
    // check what the controller returned and set the grounded value to true or false depending on collision.
	grounded = (flags  CollisionFlags.CollidedBelow) != 0;

}

:?:

6

I can’t seem to move at all in this demo.

7

Yeah that’s the whole problem :-/
Its like the vectors are fed with wrong values.

As soon as I comment out the if (!grounded) section the character
behaves okay, just like the default FPS controller.

It must be something very simple I’m not seeing :?

8

FOUND!!!

Woohooo!

Transform direction was sometimes AGAIN transformed (the old value was remembered) and this caused mayhem.

http://www.stickystudios.com/etc/har.html

Thanks