How to continue moving when I decrease speed - c#

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...)

Related

How to reduce 'speed' of a rigidbody without changing the distance it has to cover?

I am moving a rigidbody using rb.AddForce(force,ForceMode.Impulse) where force is the target position the rigidbody have to reach.
Now the speed it goes directly depends on the distance it has to cover.
Let's say the time taken to reach the target position is 3sec. I need the rigidbody to cover the same target pos in 5sec.
I dont want to change the timescale as it affects my gameflow
On Changing the velocity of rigidbody it fails to reach the target position
Some basic physics/math:
velocity = change-in-position / travel-time
force = mass * change-in-velocity / acceleration-time
For ease, we're going to call change-in-position as distance, and change-in-velocity/acceleration-time as acceleration
Now, since the acceleration-time component is effectively zero because you're using Impulse, we're going to remove it from the equation (in math terms, we set it at '1')
force = mass * change-in-velocity
Assuming your object starts at zero velocity, we can simplify change-in-velocity to just velocity
force = mass * velocity
force = mass * distance / travel-time
To bring that back into Unity code:
var mass = rb.mass;
var distance = destination.position - transform.position;
var travelTime = 5f; // seconds
var force = mass * distance / travelTime;
rb.AddForce(force, ForceMode.Impulse);
Note that this assumes a frictionless transfer and constant velocity.
If you ignore gravity, this code solves the problem, here I changed the drag according to weight and distance, it may be a little bit away from the destination at the end, the reason should be higher drag friction.
public void ForceToTarget(Transform target, float time = 1f)
{
var rb = GetComponent<Rigidbody>();
var vector = target.position - transform.position;
var distance = vector.magnitude;
rb.drag = distance/time;
rb.AddForce(vector*rb.mass*distance/time, ForceMode.Impulse);
}
If you want precise control over your speed, then stop using ForceMode.Impulse because other physics effects like drag will make your answers wrong. Instead, just set the speed yourself. You can do this with a Coroutine to control timing and ForceMode.VelocityChange to control the speed. Basically, just look at where you are, where the target is, how much time is left, and apply the speed directly.
private bool canMove = true;
public void MoveTo(Vector3 targetPosition, float targetTime)
{
if(canMove)
{
StartCoroutine(MoveToCoroutine(targetPosition,targetTime));
}
}
private IEnumerator MoveToCoroutine(Vector3 targetPosition, float time)
{
canMove = false;
while(time > 0)
{
var positionDelta = transform.position - targetPosition;
var targetSpeed = positionDelta / time;
var speedDelta = targetSpeed - rb.velocity;
rb.AddForce(speedDelta , ForceMode.VelocityChange);
yield return null;
time -= Time.deltaTime;
}
// Bring the object to a stop before fully releasing the coroutine
rb.AddForce(-rb.velocity, ForceMode.VelocityChange);
canMove = true;
}
I wrote this here into the text editor, no IDE and haven't tested it, but I'm pretty sure this'll do what you want.
Assuming you're using the target position as-is then larger vectors will cause larger force to be applied than smaller vectors. Similarly, if using a direction vector as-is then as the rb gets closer to the target the magnitute of the vector gets smaller and thus less force is applied.
To get a constant speed use the direction to the target and Normalise it instead. Regardless of the distance the direction vector will always have a magnitude of 1 so you can multiply it by any value to accurately control the speed of the object:
Rigidbody rb;
public Transform target;
public float dist;
public float speed = 2f; // or whatever
public float targetDistance = 40f; // or whatever
private void Start()
{
rb = GetComponent<Rigidbody>();
StartCoroutine("IMove");
}
IEnumerator IMove()
{
dist = Vector3.Distance(transform.position, target.position);
while (dist > targetDistance)
{
dist = Vector3.Distance(transform.position, target.position);
rb.AddForce(Vector3.Normalize(target.position - transform.position) * speed, ForceMode.Impulse);
yield return new WaitForFixedUpdate();
}
}
Without getting too much into the physics and maths, if you want it to travel slower but the same distance you need to reduce the gravity on it and the initial force.
Note in this example I am assuming the weight is 1 to make the calculation a bit easier for force.
public class TrevelSpeedAdjusted
{
public float speedFactor = 1;
void FixedUpdate()
{
// Reduce the gravity on the object
rb.AddForce(-Physics.gravity * rigidbody.mass * (1 - speedFactor));
}
public float AddAdjustedForce(Vector3 force, ForceMode forceMode)
{
rb.AddForce(force * speedFactor, forceMode);
}
}
So you can try DoTween package to do this pretty easily and its very convenient to use a package instead of using Unity's inbuilt system.
With doTween use this:
DOMove(Vector3 to, float duration, bool snapping) condition to tween your physics Gameobject to a given target position in the duration you require.
Here's documentation you can refer to if you want: http://dotween.demigiant.com/documentation.php
Let me give you an example:
Install the doTween Package. http://dotween.demigiant.com/download
Import it to unity.
Go to your script where you want to achieve the functionality you mentioned on your question and add this header "using DG.Tweening".
Now get access of your RigidBody.
For Example Lets say: I have a cube gameobject with rigidbidy and this script attached.
The Cube Initial Position is at 0,0,0.
And I want it to move to 5,5,5 in 3 seconds or 5 seconds as per your questions request. And lets say I want this to happen when I click SpaceBar on keyboard.
So I would simply do.
Rigidbody rb;
void Start()
{
rb= GetComponent<Rigibody>();
}
void Update()
{
if(Input.GetButtonDown(Keycode.Space))
{
MoveCube(new Vector3(5,5,5),5);
}
}
void MoveCube(Vector3 inTargetPosition , float durationToReachTheTarget)
{
//What this line does is first take in the target position you want your physics object to reach as it first parameter, Then takes in the duration in which you want it to reach there.
rb.DoMove(inTargetPosition,durationToReachTheTarget);
}
This should help you. But remember this is only if you okay with adding an extra package. Personally this package is very good and I would recommend you this.

I have a cube that spins all over the place when I hit an object.(the camera and character spins) UNITY

I have a simple movement that relvolves around moving foward depending on where I look. The camera is made to follow the player. The problem I am havaing is that whenever I hit an object, my character(along with the camera) start spinning crazily all over the place. (I am new to coding)
Here is the code to the movement of where my character is facing :
public class Player : MonoBehaviour {
public float movementSpeed = 10;
public float turningSpeed = 60;
public Rigidbody rb;
void Start()
{
rb = GetComponent<Rigidbody> ();
}
void Update() {
float horizontal = Input.GetAxis("Mouse X") * turningSpeed *
Time.deltaTime;
transform.Rotate(0, horizontal,0);
float vertical = Input.GetAxis("Mouse Y")* turningSpeed * Time.deltaTime;
transform.Rotate(vertical, 0, 0);
float movement = Input.GetAxis("Foward") * movementSpeed *
Time.deltaTime;
transform.Translate(0, 0,movement);
}
}
(Sorry for bad format)
The Mouse X just makes it so that it rotates on the x axis of mouse(same with y axis). The Foward is just the vertical input preset in unity.
Here is the code to the lookAt player :
public class LookAtCamera : MonoBehaviour {
public GameObject target;
void LateUpdate() {
transform.LookAt(target.transform);
}
}
Answer
I believe your rigidbody is being more heavily affected than what you desire by the bounce force occuring as you hit the object.
Possible solutions
Depending on which collider type acts as your legs, the weight of the objects involved, what behaviour you intend and more the solution can vary.
Possible solution 1:
One option is to freeze the rotation of your object on it's Rigidbody component, you can decide which axes to freeze rotation on. If freezed they can't be pushed by outside forces.
Possible solution 2:
If you wish the player to only be affected by your script you can set the rigidbody kinematic, meaning that it only is affected by scripts and animation. This is a contrast to being set to dynamic where other objects can affect it.
Possible solution 3:
Play around with the angular drag and mass of the rigidbody to slow down rotation.

Unity - Using a rigidbody for motorcycle - how do I turn?

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;
}

Unity Move rotating object

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.

Player movement starts after a few seconds after pressing the button

I'm following a tutorial on Unity 5 to create a simple stealth game.
I followed the instructions to create the script that controls the movement of the player. When I tested the game I noticed that the player takes a few seconds after pressing the button before moving.
It's as if before moving should await the conclusion of the rotation that is performed by Quaternion.Lerp.
Also pressing the x button should scream to attract attention and take proper animation.. It runs the sound but the animation is not done.. Was performed only once in multiple tests I did.
public class PlayerMovement : MonoBehaviour
{
public AudioClip shoutingClip; // Audio clip of the player shouting.
public float turnSmoothing = 15f; // A smoothing value for turning the player.
public float speedDampTime = 0.1f; // The damping for the speed parameter
private Animator anim; // Reference to the animator component.
private HashIDs hash; // Reference to the HashIDs.
void Awake ()
{
// Setting up the references.
anim = GetComponent<Animator>();
hash = GameObject.FindGameObjectWithTag(Tags.gameController).GetComponent<HashIDs>();
// Set the weight of the shouting layer to 1.
anim.SetLayerWeight(1, 1f);
}
void FixedUpdate ()
{
// Cache the inputs.
float h = Input.GetAxis("Horizontal");
float v = Input.GetAxis("Vertical");
bool sneak = Input.GetButton("Sneak");
MovementManagement(h, v, sneak);
}
void Update ()
{
// Cache the attention attracting input.
bool shout = Input.GetButtonDown("Attract");
// Set the animator shouting parameter.
anim.SetBool(hash.shoutingBool, shout);
AudioManagement(shout);
}
void MovementManagement (float horizontal, float vertical, bool sneaking)
{
// Set the sneaking parameter to the sneak input.
anim.SetBool(hash.sneakingBool, sneaking);
// If there is some axis input...
if(horizontal != 0f || vertical != 0f)
{
// ... set the players rotation and set the speed parameter to 5.5f.
Rotating(horizontal, vertical);
anim.SetFloat(hash.speedFloat, 5.5f, speedDampTime, Time.deltaTime);
}
else
// Otherwise set the speed parameter to 0.
anim.SetFloat(hash.speedFloat, 0);
}
void Rotating (float horizontal, float vertical)
{
// Create a new vector of the horizontal and vertical inputs.
Vector3 targetDirection = new Vector3(horizontal, 0f, vertical);
// Create a rotation based on this new vector assuming that up is the global y axis.
Quaternion targetRotation = Quaternion.LookRotation(targetDirection, Vector3.up);
// Create a rotation that is an increment closer to the target rotation from the player's rotation.
Quaternion newRotation = Quaternion.Lerp(GetComponent<Rigidbody>().rotation, targetRotation, turnSmoothing * Time.deltaTime);
// Change the players rotation to this new rotation.
GetComponent<Rigidbody>().MoveRotation(newRotation);
}
void AudioManagement (bool shout)
{
// If the player is currently in the run state...
if(anim.GetCurrentAnimatorStateInfo(0).nameHash == hash.locomotionState)
{
// ... and if the footsteps are not playing...
if(!GetComponent<AudioSource>().isPlaying)
// ... play them.
GetComponent<AudioSource>().Play();
}
else
// Otherwise stop the footsteps.
GetComponent<AudioSource>().Stop();
// If the shout input has been pressed...
if(shout)
// ... play the shouting clip where we are.
AudioSource.PlayClipAtPoint(shoutingClip, transform.position);
}
}
I'm new in unity so I might need some more explanation. Thanks to everyone!
The first issue, delaying your player movement, may be caused by the line
anim.SetFloat(hash.speedFloat, 5.5f, speedDampTime, Time.deltaTime);
The potential issue is that you are calling Time.deltaTime, which is intended to be use inside an update() call. Your function is called inside of fixedUpdate() which means you should be using Time.fixedDeltaTime.
For your second issue, shouting, the code seems fine and the issue is likely in your animation tree. Check that the state you are in before shouting can transition to shout, and checks for the correct trigger.

Categories

Resources