DotNet script changes transform

GlitchyEngineHelper/DotNetScriptingHelper/QuaternionExtensions.cs

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+using System.Numerics;
+
+namespace DotNetScriptingHelper;
+
+public static class QuaternionExtensions
+{
+    public static (Vector3 Axis, float Angle) ToAxisAngle(this Quaternion quat)
+	{
+        // scalar part = cos(θ/2)
+        // So, we can extract the angle directly.
+        float angle = 2.0f * MathF.Acos(quat.W);
+
+        // vector part = axis * sin(θ/2)
+        // In other words, the vector part is the axis, but with length of sin(θ/2).
+        // We assume quaternion is unit length, so subtracting w^2 gives us length of just vector part (aka sin(θ/2)).
+        float length = MathF.Sqrt(1.0f - (quat.W * quat.W));
+
+        Vector3 axis;
+
+        // Normalize vector part to get the axis!
+        if (length == 0)
+        {
+            axis = Vector3.Zero;
+        }
+        else
+        {
+            length = 1.0f / length;
+            axis.X = quat.X * length;
+            axis.Y = quat.Y * length;
+            axis.Z = quat.Z * length;
+        }
+
+        return (axis, angle);
+	}
+
+    public static Vector3 ToEulerAngles(this Quaternion q)
+    {
+        // http://www.euclideanspace.com/maths/geometry/rotations/conversions/quaternionToEuler/
+
+        Vector3 result;
+
+        float sqw = q.W * q.W;
+        float sqx = q.X * q.X;
+        float sqy = q.Y * q.Y;
+        float sqz = q.Z * q.Z;
+        float unit = sqx + sqy + sqz + sqw; // if normalised is one, otherwise is correction factor
+        float test = q.X * q.Y + q.Z * q.W;
+        if (test > 0.4999f * unit)
+        { // singularity at north pole
+            result.Y = 2.0f * MathF.Atan2(q.X, q.W);
+            result.Z = MathF.PI / 2.0f;
+            result.X = 0.0f;
+            return result;
+        }
+        if (test < -0.4999f * unit)
+        { // singularity at south pole
+            result.Y = -2.0f * MathF.Atan2(q.X, q.W);
+            result.Z = -MathF.PI / 2.0f;
+            result.X = 0.0f;
+            return result;
+        }
+        result.Y = MathF.Atan2(2 * q.Y * q.W - 2 * q.X * q.Z, sqx - sqy - sqz + sqw);
+        result.Z = MathF.Asin(2 * test / unit);
+        result.X = MathF.Atan2(2 * q.X * q.W - 2 * q.Y * q.Z, -sqx + sqy - sqz + sqw);
+
+        return result;
+    }
+}