Question by danielbarta · Aug 14, 2020 at 10:30 AM · rotation rigidbody rigidbody2d

Limit rotation on dynamic rigidbody

Hi! I have a player character which uses dynamic rigidbody. I want to use the built-in physics, but with a few exceptions. I want to constraint rotation and fall velocity, also speed and rotation itself.

I move and rotate my character using forces in FixedUpdate, and apply the constraints on LateUpdate.

 void FixedUpdate()
     {
         if (!isLocalPlayer)
         {
             return;
         }
 
         Move();
         Rotate();
     }
 
     private void LateUpdate()
     {
         if (!isLocalPlayer)
         {
             return;
         }
 
         ConstraintFallVelocity();
         ConstraintRotation();
         ConstraintRotationVelocity();
         ConstraintSpeed();
     }
 
     void Move()
     {
 
         if ((Input.GetKey(KeyCode.Space) || Input.GetMouseButton(0)) && !_spacePressed)
         {
             CmdShoot();
             Vector2 velocityNorm = _rigidbody.velocity.normalized;
             Vector2 velocityNormMirrored = new Vector2(velocityNorm.x, Mathf.Abs(velocityNorm.y));
             if (velocityNormMirrored.y == 0f)
             {
                 velocityNormMirrored.y = 1;
             }
             velocityNormMirrored.x = velocityNormMirrored.x * -1;
             _rigidbody.AddForce(VectorHelpers.Rotate(VectorHelpers.DegreeToVector2(_rigidbody.rotation), 90).normalized * _force);
             _spacePressed = true;
         }
 
         if ((!Input.GetKey(KeyCode.Space) && !Input.GetMouseButton(0)) && _spacePressed)
         {
             _spacePressed = false;
         }
     }
 
     void Rotate()
     {
         float input;
         if (Mathf.Abs(Input.acceleration.x) > Mathf.Abs(Input.GetAxis("Horizontal")))
         {
             input = Input.acceleration.x;
         } else
         {
             input = Input.GetAxis("Horizontal");
         }
         _rigidbody.AddTorque(input * _rotationSpeed * -1);
     }
 
     void ConstraintFallVelocity()
     {
         if (_rigidbody.velocity.y < _maxFallVelocity * -1)
         {
             _rigidbody.velocity = _maxFallVelocity * _rigidbody.velocity.normalized;
         }
     }
 
     void ConstraintRotation()
     {
         float rotationX = transform.eulerAngles.z;
         Vector3 euler = transform.eulerAngles;
 
         bool clamped = false;
         // euler.z is between 0 and 360. For example, if it is rotated left it is 10, if rotated right, it is 350
         if (euler.z > 180 && 360 - euler.z > _maxRotation)
         {
             clamped = true;
             euler.z = 360 - _maxRotation;
         } else if (euler.z < 180 && euler.z > _maxRotation)
         {
             clamped = true;
             euler.z = _maxRotation;
         }
 
         if (clamped)
         {
             _rigidbody.angularVelocity = 0;
             transform.eulerAngles = euler;
         }
     }
 
     void ConstraintRotationVelocity()
     {
         _rigidbody.angularVelocity = Mathf.Clamp(_rigidbody.angularVelocity, -_maxAngularVelocity, _maxAngularVelocity);
     }
 
     void ConstraintSpeed()
     {
         if (Mathf.Abs(_rigidbody.velocity.x) > _maxSpeed || Mathf.Abs(_rigidbody.velocity.y) > _maxSpeed)
         {
             // clamp velocity:
             Vector3 newVelocity = _rigidbody.velocity.normalized;
             newVelocity *= _maxSpeed;
             _rigidbody.velocity = newVelocity;
         }
     }

When I rotate, and the max rotation is reached, I experience a small jump in character movement. I think it is because though I took care of rotation limit, the new position has already been calculated.

Is there a right way to do this using dynamic rigidbody?

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