Character controller without Deltatime

Question

Hi. I want to know is it necessary to use Time.deltatime for FPS character controller script? for example in this script :

void Update() { Vector3 forward = transform.TransformDirection(Vector3.forward); Vector3 right = transform.TransformDirection(Vector3.right);

     float curSpeedX = walkingSpeed * Input.GetAxis("Vertical");
     float curSpeedY = walkingSpeed* Input.GetAxis("Horizontal");

     float movementDirectionY = moveDirection.y;
     moveDirection = (forward * curSpeedX) + (right * curSpeedY);

     if (Input.GetButton("Jump") && canMove && characterController.isGrounded)
     {
         moveDirection.y = jumpSpeed;
     }
     else
     {
         moveDirection.y = movementDirectionY;
     }

     if (!characterController.isGrounded)
     {
         moveDirection.y -= gravity * Time.deltaTime;
     }

     characterController.Move(moveDirection * Time.deltaTime);
 }

If we remove Time.deltaTime and reduce some values like "gravity", or "walkspeed" the script works fine.

But I don't understand why in all the examples that I have seen over the internet , Time.deltatime is used ? even in other scripts like mouselook.

Is it necessary to use Time.deltatime?

Answer 1

Answer by MrRutabaga · Aug 08, 2021 at 03:10 AM

Time.deltaTime is the number of seconds between the last frame and the current one.

I you don't use it, as you see, it works fine...

But not exactly.

Time.deltaTime is used to remove unpredictible change of speed (among other problems) due to FPS changes.

Imagine a character going at a speed of 5, meaning he's going 5 units a second. If you don't use deltaTime and going from 60 to 30 fps, your character will move 2.5 units a second.

That's really simple but it's the basic. Always use Time.deltaTime when doing physics and frame dependent movements.

Add comment · Share

Character controller without Deltatime

1 Reply

Your answer

Follow this Question

Related Questions