Rotate a plane at x axis while fixing its y and z initial rotation value

[TifaOng]

Hi,

I have a plane that is already fixed at rotation (270, 0, 0) in Unity scene. What I wanna do now is to rotate the the plane around x axis, while mainting y and z at 0.
When rotating, the direction to face is Vector3 moveDirection (for example).

Secondly, how to change the value of x or y or z rotation value and fix them when necessary?

For example,

If moveDirection = right,
Rotation (x, -630, -1530); //x is a changing value based on moveDirection
if moveDirection = left,
Rotation (x, -1170, 990);

For your information, I get the values above by rotating my plane.

I searched around ways to do it but all of them do not have fixing a rotation value while rotating. Please help.

Thanks in advance.

[aldonaletto]

This is a good case for eulerAngles: save the initial eulerAngles in a member variable and “rotate” mathematically the angles, then assign the variable to eulerAngles:

public var rotationSpeed: float = 60; // 60 degrees per second

private var euler: Vector3;

function Start(){
  // get the initial eulerAngles:
  euler = transform.eulerAngles;
}

function Update(){
  // rotate mathematically about X:
  euler.x = (euler.x + rotationSpeed * Time.deltaTime) % 360;
  // update object rotation:
  transform.eulerAngles = euler;
}

You can modify the other angles at any time - but do it in the euler variable, not directly in transform.eulerAngles: any change in the euler variable will be transferred to the object inside Update.

[tWayfarer]

If you want to only rotate a single axis, you can do something like:

tempRotation = currentRotation;

tempRotation.x += rotateSpeed;

currentRotation = tempRotation;

This way, the y or z axis won’t change, but x will.