Vector3 of rotation comparison fails

Questions & Answers
1

Hi all,

I’m trying to create a rotation puzzle, where 4 objects need to be aligned to specific angles for the solution. There are 4 buttons that each rotate 2 objects 90 degrees clockwise.

Here’s the code for the Manager:

class RotationPuzzleManager (MonoBehaviour): 
	public listOfTwisties as (GameObject)
	public rotationSolution as (Vector3)

	def Execute (clickedObject as GameObject):
		currentTwistieRotations as List = []
		for eachTwistie in listOfTwisties:
			currentTwistieRotations.Add(eachTwistie.GetComponent[of RotationPuzzleTwistie]().GetTargetRotation())
		currentTwistieVectors as (Vector3) = array(Vector3, currentTwistieRotations)
		if currentTwistieVectors == rotationSolution:
			print ("YOU WIN!!!")

Where GetTargetRotation() returns Quaternion.Euler(targetRotation).eulerAngles
and targetRotation is where the Twisties are rotating to.

The angles are always right angles (0, 90, 180, 270) and the code above works… sometimes. Sometimes the comparison (currentTwistieVectors == rotationSolution) fails when the angle is 0 or 180, eg ((0.0,0.0,0.0) == (0.0,0.0,0.0)) OR ((0.0,180.0,0.0) == (0.0,180.0,0.0)).

What am I doing wrong? Any help would be greatly appreciated.

2

Might be floating point errors…
Try something like this:
diff as (Vector3) = currentTwistieVectors - rotationSolution;
if diff.magnitude<0.1f
print(“YOU WIN!!!”);

3

Quaternions are a “double cover,” which means there are two ways two store each rotation. In other words (0,180,0) is also (0,-180,0) but also something odd like (-90,270,90). Unity usually gives you the “obvious” one, but not always.

Maybe print out currentTwistyVectors and check. Lots of numbers, so maybe print all on one line with w=""; w+=pieceName+curTwstVec;. Or limit with if(eachTwisty==middlePiece) and just change middlePiece and watch the numbers.

If that is that problem, but there are too many combos (maybe sometimes it thinks (0,0,0) is (360,720,0)) you could instead use Quaternion.Angle to compare current/actual. It “knows” that 360==0, and so on.