internal static FaceDir RotateBy(this FaceDir faceDir, Rotation r)
{
var f = faceDir.Forward();
var x1 = (int)f.x;
var z1 = (int)f.z;
var(x2, z2) = TopoArrayUtils.SquareRotateVector(x1, z1, r);
if (x1 == x2 && z1 == z2)
{
return(faceDir);
}
if (x2 == 1)
{
return(FaceDir.Right);
}
if (x2 == -1)
{
return(FaceDir.Left);
}
if (z2 == 1)
{
return(FaceDir.Forward);
}
if (z2 == -1)
{
return(FaceDir.Back);
}
throw new System.Exception();
}
/// <summary>
/// Given a FaceDetails on given face of the cube,
/// rotates the cube, and returns the new face and correctly oriented FaceDetails
/// </summary>
internal static (FaceDir, FaceDetails) ApplyRotator(FaceDir faceDir, FaceDetails faceDetails, MatrixInt3x3 rotator)
{
var rotatedFaceDirForward = rotator.Multiply(faceDir.Forward());
var rotatedFaceDirUp = rotator.Multiply(faceDir.Up());
var rotatedFaceDirRight = rotator.Multiply(Vector3.Cross(faceDir.Forward(), faceDir.Up()));
var rotatedFaceDir = FromNormal(rotatedFaceDirForward);
var trueUp = rotatedFaceDir.Up();
var trueForward = rotatedFaceDirForward; // = rotatedFaceDir.Forward();
var trueRight = Vector3.Cross(trueForward, trueUp);
// Find the rotation that will map rotatedFaceDirUp to trueUp
// and rotatedFaceDirRight to trueRight
var dot = Vector3.Dot(rotatedFaceDirUp, trueUp);
var cross = Vector3.Dot(rotatedFaceDirUp, trueRight);
Rotation faceRot;
if (dot == 1)
{
faceRot = new Rotation();
}
else if (dot == -1)
{
faceRot = new Rotation(180);
}
else if (cross == 1)
{
faceRot = new Rotation(270);
}
else if (cross == -1)
{
faceRot = new Rotation(90);
}
else
{
throw new Exception();
}
if (Vector3.Dot(Vector3.Cross(rotatedFaceDirForward, rotatedFaceDirUp), rotatedFaceDirRight) < 0)
{
faceRot = new Rotation(360 - faceRot.RotateCw, true);
}
var rotatedFaceDetails = faceDetails.RotateBy(faceRot);
return(rotatedFaceDir, rotatedFaceDetails);
}
