I'm new to Unity and rigidbodies, and I thought I'd learn by trying to make a 3D Tron Light-cycle game. I've made my player vehicle using a combination of cylinders, spheres, and rectangles, seen below:
I used a rigid body on the elongated sphere, and used the following code:
public float accel = 1.0f;
// Use this for initialization
void Start () {
cycleSphere = GetComponent<Rigidbody>();
}
void FixedUpdate () {
cycleSphere.velocity = Vector3.forward * accel;
}
That moves the vehicle forwards. I'm not sure if there's a better way to do this, but if there is, please do say so.
I've attached the Main camera to the vehicle, and disabled X rotation to prevent it and the camera from rolling.
Now I would like to get it to turn by pressing the A and D buttons. Unlike the 90 degree turning of the original Tron light-cycles, I wanted it to turn like a regular vehicle.
So I tried this:
void Update () {
if (Input.GetKey (KeyCode.A)) {
turning = true;
turnAnglePerFixedUpdate -= turnRateAngle;
} else if (Input.GetKey (KeyCode.D)) {
turning = true;
turnAnglePerFixedUpdate += turnRateAngle;
} else {
turning = false;
}
}
void FixedUpdate () {
float mag = cycleSphere.velocity.magnitude;
if (!turning) {
Quaternion quat = Quaternion.AngleAxis (turnAnglePerFixedUpdate, transform.up);// * transform.rotation;
cycleSphere.MoveRotation (quat);
}
cycleSphere.velocity = Vector3.forward * accel;
}
While the above code does rotate the vehicle, it still moves in the last direction it was in - it behaves more like a tank turret. Worse, pressing either A or D too much would cause it to rotate in the desired direction and, after a short while, go nuts, rotating this way and that, taking the camera with it.
What did I do wrong and how can I fix it?
First of all I would recommend you to change from Input.GetKey to Input.GetAxis which will gracefully increase or decrease it's value when the key is pressed. This will give you the option to normalize the force vector applied as your velocity. Then based on that vector you have to adapt your force input so that the "front wheel" will "drag" the rest of the body to some other direction ( left or right ). This is not the ideal "real world physics behavior" because the forward force is slightly bigger than the side ( left or right ) force.
code example :
// member fields
float sideForceMultiplier = 1.0f;
float frontForceMultiplier = 2.0f;
Vector3 currentVeloticy = Vector3.zero;
void Update()
{
Vector3 sideForce = (sideForceMultiplier * Input.GetAxis("horizontal")) * Vector3.right;
Vector3 frontForce = frontForceMultiplier * Vector3.forward;
currentVelocity = (sideForce + fronForce).Normalize;
}
void FxedUpdate()
{
cycleSphere.velocity = currentVelocity * accel;
}
Related
using UnityEngine;
public class ThirdPersonMovement : MonoBehaviour
{
Rigidbody rb;
private Animator animator;
public float speed = 5f;
void Start() {
animator = GetComponent<Animator>();
rb = GetComponent<Rigidbody>();
}
// Update is called once per frame
void Update()
{
//Get player input based on world space.
float playerHorizontalInput = Input.GetAxisRaw("Horizontal");
float playerVerticalInput = Input.GetAxisRaw("Vertical");
//Get camera-normalized directional vectors
Vector3 forward = Camera.main.transform.forward;
Vector3 right = Camera.main.transform.right;
//Create direction-relative input vectors
Vector3 forwardRelativeVerticalInput = playerVerticalInput * forward;
Vector3 rightRelativeHorizontalInput = playerHorizontalInput * right;
Vector3 cameraRelativeMovement = forwardRelativeVerticalInput + rightRelativeHorizontalInput;
Vector3 movement = cameraRelativeMovement * speed * Time.deltaTime;
rb.MovePosition(transform.position + movement);
transform.forward = cameraRelativeMovement;
if (cameraRelativeMovement != Vector3.zero)
{
animator.SetBool("IsMoving", true);
}
else {
animator.SetBool("IsMoving", false);
}
}
}
I know similar questions have been posted before but I haven't been able to find a solution to what I'm experiencing.
I have the code above and it is linked to a character with a rigidbody component and 'is kinematic' checked. When I try to move, the character doesn't move for ages and then randomly jumps forward a random distance and doesn't do it again until I hit W again.
This has worked before when I used transform.Translate but obviously my character ran through the floor when the camera pointed down so I was trying to fix the issue.
A few things I notice about your code. You said this method used to work with transform.translate but not anymore, this tells me that your movement vectors are probably fine up until the point you changed them for this implementation (my guess is everything is the same except when you added tranform.position to your vector, since the function doesn't take speed, it takes position). You could try testing tranform.position + movement or just movement with a Debug.Log() statement, but that's probably not your issue.
Since you said this issue only started when you changed the function you use to move the player, I would try just inputting a non-changing Vector3 into the movement function: rb.movePosition(tranform.position + new Vector3(1,0,0)); or something like that, just to see if the movement function is even working.
I'm totally new to Unity and game development...I made a 2D object of the car that can move to 8 directions....each direction with the specific animation of the car's movement...Now, how do I make my car move in such a way that if it's moving straight LEFT it shouldn't go immediately straight to RIGHT when turning RIGHT, so I want it to make a proper round turn or a "U TURN" to move towards its opposite direction and obviously the same with UP and DOWN turns....can anyone please help me in at least one way I can fix this?
or the other way to ask this question would be if I'm moving my object to x = -1 direction then on turning to x = 1 it should first go through x = 0 and then x = 1 so that it looks like a turn.
this is the code for my CAR so far..
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class CARmovement : MonoBehaviour
{
public float speed;
private Rigidbody2D myRigidbody;
private Vector3 change;
private Animator animator;
private Vector3 lastMoveDirection;
// Start is called before the first frame update
void Start()
{
animator = GetComponent<Animator>();
myRigidbody = GetComponent<Rigidbody2D>();
}
// Update is called once per frame
void Update()
{
change = Vector3.zero;
change.x = Input.GetAxis("Horizontal");
change.y = Input.GetAxis("Vertical");
UpdateAnimationAndMove();
}
void UpdateAnimationAndMove()
{
if (change != Vector3.zero)
{
MoveCar();
animator.SetFloat("moveX", change.x);
animator.SetFloat("moveY", change.y);
animator.SetBool("driving", true);
}
else
{
animator.SetBool("driving", false);
}
}
void MoveCar()
{
myRigidbody.MovePosition(transform.position + change * speed * Time.deltaTime);
}
}
I try an example of rotating a car. We add an object (here I add a car as an example), select the object (car) to create a C# Script script, double-click to open, we define two variables Speed_move, Speed_rot to control the movement speed and Rotation speed and assign values to them. We use Translate to control the forward and backward movement of the cube through the W and S buttons, forward with forward, and back with back; use Rotate to control the rotation of the object through the A and D buttons, up is the Y-axis rotation. The following is the code for the specific rotation.
if (Input.GetKey(KeyCode.W))
{
this.transform.Translate(Vector3.forward * Time.deltaTime * Speed_move);
}
if (Input.GetKey(KeyCode.S))
{
this.transform.Translate(Vector3.back * Time.deltaTime * Speed_move);
}
if (Input.GetKey(KeyCode.A))
{
this.transform.Rotate(Vector3.up * Time.deltaTime * -Speed_rot);
}
if (Input.GetKey(KeyCode.D))
{
this.transform.Rotate(Vector3.up * Time.deltaTime * Speed_rot);
}
I am creating a game that is set in Zero-gravity. I am using a script that can be found here https://github.com/brihernandez/ArcadeSpaceFlightExample
The movement is controlled by a throttle that can be increased/decreased using the mouse wheel or 'w' and 's' keys.
This code controls the mouse wheel and is the same for the 'w' and 's' keys.
private void UpdateMouseWheelThrottle()
{
throttle += Input.GetAxis("Mouse ScrollWheel");
throttle = Mathf.Clamp(throttle, 0.0f, 1.0f);
}
The object that is accelerated by the throttle stops moving when I decrease the throttle and does not drift or continue moving as it should in zero gravity.
This is the code that controls the physics.
public class PlayerPhysics: MonoBehaviour
{
[Tooltip("X: Lateral thrust\nY: Vertical thrust\nZ: Longitudinal Thrust")]
public Vector3 linearForce = new Vector3(100.0f, 100.0f, 100.0f);
[Tooltip("X: Pitch\nY: Yaw\nZ: Roll")]
public Vector3 angularForce = new Vector3(100.0f, 100.0f, 100.0f);
[Range(0.0f, 1.0f)]
[Tooltip("Multiplier for longitudinal thrust when reverse thrust is requested.")]
public float reverseMultiplier = 1.0f;
[Tooltip("Multiplier for all forces. Can be used to keep force numbers smaller and more readable.")]
public float forceMultiplier = 100.0f;
public Rigidbody Rigidbody { get { return rbody; } }
private Vector3 appliedLinearForce = Vector3.zero;
private Vector3 appliedAngularForce = Vector3.zero;
private Rigidbody rbody;
private Player player;
void Awake()
{
rbody = GetComponent<Rigidbody>();
if (rbody == null)
{
Debug.LogWarning(name + ": ShipPhysics has no rigidbody.");
}
player = GetComponent<Player>();
}
void FixedUpdate()
{
if (rbody != null)
{
rbody.AddRelativeForce(appliedLinearForce * forceMultiplier, ForceMode.Force);
rbody.AddRelativeTorque(appliedAngularForce * forceMultiplier, ForceMode.Force);
}
}
public void SetPhysicsInput(Vector3 linearInput, Vector3 angularInput)
{
appliedLinearForce = MultiplyByComponent(linearInput, linearForce);
appliedAngularForce = MultiplyByComponent(angularInput, angularForce);
}
private Vector3 MultiplyByComponent(Vector3 a, Vector3 b)
{
Vector3 ret;
ret.x = a.x * b.x;
ret.y = a.y * b.y;
ret.z = a.z * b.z;
return ret;
}
}
And here is the code that instantiates both.
public class Player: MonoBehaviour
{
public static Player Playerdrone { get { return player; } }
private static Player player;
private PlayerInput input;
private PlayerPhysics physics;
public Vector3 Velocity { get { return physics.Rigidbody.velocity; } }
public float Throttle { get { return input.throttle; } }
// Start is called before the first frame update
void Awake()
{
input = GetComponent<PlayerInput>();
physics = GetComponent<PlayerPhysics>();
}
// Update is called once per frame
void Update()
{
physics.SetPhysicsInput(new Vector3(input.strafe, 0.0f, input.throttle), new Vector3(input.pitch, input.yaw, input.roll));
}
}
I cannot get the Rigidboy to keep drifting when I decrease the throttle, my option is to either abandon the throttle concept and use a simple "Addforce" but I would prefer to keep it.
I have edited the script to have a similar function to the 'Roll' that used 'w' and 's' but moves me forwards and backward. I still find myself decelerating when I let go of the input.
Lowering drag and angular causes the object to spin out of control due to the mouse following function. The mouse does not center the camera and instead causes the camera to keep rotating and tracking the mouse. Changing the mouse script will cause it's own issues since it controls the pitch and yaw of the object.
private void SetStickCommandsUsingMouse()
{
Vector3 mousePos = Input.mousePosition;
// Figure out most position relative to center of screen.
// (0, 0) is center, (-1, -1) is bottom left, (1, 1) is top right.
pitch = (mousePos.y - (Screen.height * 0.5f)) / (Screen.height * 0.5f);
yaw = (mousePos.x - (Screen.width * 0.5f)) / (Screen.width * 0.5f);
// Make sure the values don't exceed limits.
pitch = -Mathf.Clamp(pitch, -1.0f, 1.0f);
yaw = Mathf.Clamp(yaw, -1.0f, 1.0f);
}
The object that is accelerated by the throttle stops moving when I decrease the throttle and does not drift or continue moving as it should in zero gravity.
The Rigidbody component has properties that can be changed in the Inspector (documented here) (and also via script (documented here)):
Mass: The mass of the object (in kilograms by default).
Drag: How much air resistance affects the object when moving from forces. 0 means no air resistance, and infinity makes the object
stop moving immediately.
It sounds like your Drag value might be too large (?).
Although this example project uses "space mechanics" (effectively with no air resistance), the Drag property can still be used to tune the movement and "drift behavior" of the rigidbody, and to control how long it will keep decelerating after the throttle value went down to 0.
Alternatively, you could try to experiment with other ForceMode parameters for the Add*Force() calls: ForceMode.Acceleration or ForceMode.VelocityChange (which is ignoring the mass of the rigidbody).
To make your game more "realistic", you could instead set the Drag property to 0 (no air resistance like in real space -> infinite drift), and try to actively decelerate the ship by experimenting with retrograde rockets/thrusters, by adding a force in backward direction. However, that's probably quite impractical for an arcade game, I guess.
There are also the global Physics settings of the project, which can be found under Edit -> Project settings -> Physics (documented here). There, you'll also find many important physics settings (like Gravity, for example).
(It can also be interesting to have a look at the official docs of the PhysX physics engine, which Unity uses internally for its 3D physics, to understand how things actually work under the hood...)
I have a character/rigidbody and 'she' can turn around. When I press Play in Unity, if I move forward/backward, that's fine, she moves forward/backward. It's a good start.
But then if I turn her left or right, then go forward/backward, she now moves sideways.
She is a rigidbody component set as a parent in the scene.
Surely it's not difficult to do, but I can't figure out how to set her rotation so that when she turns, she will move 'forward' when I press the button to move her forward! There are plenty of first-person-shooter games where you can turn and move 'forward' and the player goes in the correct direction.
My rotation script at the moment is this:
Vector3 EulerAngleVelocity;
public float rotateSpeed = 250.0f;
void Update() {
if (Input.GetKey(KeyCode.UpArrow) || Input.GetKey(KeyCode.DownArrow))
{
MoveVector = PoolInput();
Move();
}
if (Input.GetKey(KeyCode.RightArrow))
{
EulerAngleVelocity = new Vector3(0, rotateSpeed, 0);
Quaternion deltaRotation = Quaternion.Euler(EulerAngleVelocity * Time.deltaTime);
rigidbody.MoveRotation(rigidbody.rotation * deltaRotation);
}
}
private void Move()
{
rigidbody.AddForce((MoveVector * moveSpeed));
}
private Vector3 PoolInput()
{
Vector3 dir = Vector3.zero;
dir.x = joystick.Horizontal();
dir.z = joystick.Vertical();
if (dir.magnitude > 1)
dir.Normalize();
return dir;
}
You're moving your joystick and adding that direction in relation to the WORLD instead of in relation to your player. If you want to add force relative to the orientation of the RigidBody probably what you want to use is rigidBody.AddRelativeForce (documentation) instead of simply rigidBody.AddForce.
Your problem isn't your rotation code, it's your movement code. You're applying a motion in world-space, not local-space ('object'-space).
For example, if you're using Vector3.Forward, you will want to use transform.Forward instead.
I have a ball which rotates around the point 0,0,0 in the Z-axis. When the space button is pressed, the ball has to go inside the large circle. Now my code looks like this. When you press space, the ball does not behave as they should. I want to know how to make a balloon down exactly down
that's how the ball should behave ->
behavior image
my code:
void Update () {
if (Input.GetKeyDown (KeyCode.Space)) {
transform.position = new Vector3 (transform.position.x - 1, transform.position.y - 1, 0);
} else {
transform.RotateAround(new Vector3(0,0,0), new Vector3(0,0,1), 2);
}
}
Your code to 'jump' the orbit doesn't do what you want because Transform.RotateAround modifies both the rotation and the position of the object's transform.
So jumping to (position - 1,1,0) in the world is going to return wildly different results every time.
What you want to do instead is calculate the (Vector) direction from the object to the centre of orbit (the difference), then scale that down to how far you want it to move, then apply it to the position.
private Vector3 _orbitPos = Vector3.zero;
private float _orbitAngle = 2f;
private float _distanceToJump = 2f;
void Update()
{
if (Input.GetKeyDown(KeyCode.Space))
{
var difference = (_orbitPos - transform.position).normalized * _distanceToJump;
transform.Translate(difference);
}
transform.RotateAround(_orbitPos, Vector3.forward, _orbitAngle);
}
This will move the object to be orbiting 2 units closer when space is pressed immediately.
If you wanted to have a smooth transition instead of a jump, look into using Mathf.Lerp, Vector3.Lerp and the routines involved.