After multiple transform.Rotate, align with an axis?

Unity Engine
1

After multiple rotations about the Z axis such as:

transform.Rotate(0, 0, rotateMagnitude);

is it easily possible to make transform align with the Y axis? I.E. if transform started off being aligned with the Y axis, is there an easy way to get the transform back to its initial alignment?

2

The easiest way to do this is to save the initial position before rotating and just restore it afterwards.

3

@andeeee:

Can you tell me how to restore the initial rotation? I know how to restore the initial position, but if the initial rotation is zero, that doesn’t help. I.E. I need to undo all of the rotations that have occurred.

4

Wouldn’t you just store it a variable??? I mean like, maybe write something like “var initialRotation:Quaternion = transform.rotation;”? It shouldn’t be too hard, I think, unless I don’t understand what you’re saying.

5

@ liars_paradox:

If I instantiate the Game Object as below the GO will be aligned with the Y axis:

var InitialRot    : Quaternion = Quaternion.identity;
var GO : GameObject;

GO         = (Instantiate(Prefab, InitialPos, InitialRot));

Then I will rotate the GO about the z axis multiple times, so that the GO is no longer aligned with the Y axis.

If I rotate GO about the z axis multiple times, do I need to store the cummulative rotations to figure out how much rotation to undo? Because if I use InitialRot, since it is no rotation, it won’t get the GO to align with the Y axis again.

6

Don’t undo any Rotations.

Quaternion initialRot = Quaternion.Identity;

void Start()
{
initialRot = transform.rotation;
}

void revert()
{
transform.rotation = initialRot;
}

This sets up initialRot by default to along the Y axis, but it will also save the rotation on Object instantiation if you want to instantiate it to a different orientation than on the y. This allows you to revert to original. And if you want to save a new Orientation to Revert, just set initialRot again.

Edit: In your context:

var InitialRot : Quaternion = Quaternion.identity;
var GO : GameObject;

GO = (Instantiate(Prefab, anyPosition, anyRotation));

initialRot = GO.transform.rotation;

Revert()
{
transform.rotation = intialRot;
}

7

@ Ntero:

Sweet, that worked. Thanks!