using UnityEngine;

public static class Bezier
{
	public static Vector3 GetPoint(Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t)
	{
		t = Mathf.Clamp01(t);
		float num = 1f - t;
		return num * num * num * p0 + 3f * num * num * t * p1 + 3f * num * t * t * p2 + t * t * t * p3;
	}

	public static Vector3 GetFirstDerivative(Vector3 p0, Vector3 p1, Vector3 p2, Vector3 p3, float t)
	{
		t = Mathf.Clamp01(t);
		float num = 1f - t;
		return 3f * num * num * (p1 - p0) + 6f * num * t * (p2 - p1) + 3f * t * t * (p3 - p2);
	}

	public static float GetTotalLenght(Vector3[] points)
	{
		float num = 0f;
		for (int i = 0; i < points.Length - 3; i += 3)
		{
			if (points.Length >= 3)
			{
				num += BezierSingleLength(new Vector3[4]
				{
					points[i],
					points[i + 1],
					points[i + 2],
					points[i + 3]
				});
			}
		}
		return num;
	}

	public static float BezierSingleLength(Vector3[] p)
	{
		Vector3 lhs = p[0] - p[1];
		Vector3 vector = p[2] - p[1];
		Vector3 vector2 = default(Vector3);
		Vector3 rhs = p[3] - p[2];
		float magnitude = lhs.magnitude;
		float magnitude2 = vector.magnitude;
		float magnitude3 = rhs.magnitude;
		if (magnitude > 0f)
		{
			lhs /= magnitude;
		}
		if (magnitude2 > 0f)
		{
			vector /= magnitude2;
		}
		if (magnitude3 > 0f)
		{
			rhs /= magnitude3;
		}
		vector2 = -vector;
		float num = Mathf.Abs(Vector3.Dot(lhs, vector)) + Mathf.Abs(Vector3.Dot(vector2, rhs));
		if (num > 1.98f || magnitude + magnitude2 + magnitude3 < (4f - num) * 8f)
		{
			return magnitude + magnitude2 + magnitude3;
		}
		Vector3[] array = new Vector3[4];
		Vector3[] array2 = new Vector3[4];
		array[0] = p[0];
		array[1] = (p[0] + p[1]) * 0.5f;
		Vector3 vector3 = (p[1] + p[2]) * 0.5f;
		array[2] = (array[1] + vector3) * 0.5f;
		array2[3] = p[3];
		array2[2] = (p[2] + p[3]) * 0.5f;
		array2[1] = (array2[2] + vector3) * 0.5f;
		array2[0] = (array2[1] + array[2]) * 0.5f;
		array[3] = array2[0];
		return BezierSingleLength(array) + BezierSingleLength(array2);
	}
}