c# 写一个计算方法，需求是已知原始坐标系中两个坐标点的实际坐标在目标坐标系中的对应坐标，求旋转平移矩阵，然后使用这个矩阵写一个方法将原始坐标系中的其他坐标映射到目标坐标系

在C#中，你可以创建一个`Matrix4x4`类来表示旋转和平移变换的矩阵，因为矩阵可以很好地处理这两种变换。首先，你需要定义一个方法来计算旋转和平移的组合矩阵，假设我们已经有了原始坐标`Point original`和目标坐标`Point target`：

using System.Numerics;

public class Matrix4x4
{
    public float[] Elements = new float[16]; // 4x4 matrix

    // 定义一个方法计算旋转和平移矩阵
    public Matrix4x4 ComputeTransformation(Point original, Point target)
    {
        Vector3 rotationAxis; // 假设需要先确定旋转轴
        float angle; // 旋转角度
        // ... 实现旋转部分，这里省略细节
        // 另外，获取平移向量delta
        Vector3 translation = target.Position - original.Position;

        // 构建旋转和平移矩阵
        float sinAngle = (float)Math.Sin(angle);
        float cosAngle = (float)Math.Cos(angle);
        float oneMinusCosAngle = 1f - cosAngle;
        
        this.Elements[0] = cosAngle;
        this.Elements[4] = -sinAngle;
        this.Elements[8] = 0f;
        this.Elements[12] = sinAngle * translation.X + oneMinusCosAngle * original.Y * translation.Z;
        this.Elements[1] = sinAngle;
        this.Elements[5] = cosAngle;
        this.Elements[9] = -original.X * translation.Y + oneMinusCosAngle * original.Z * translation.X;
        this.Elements[13] = -(oneMinusCosAngle * original.Y * translation.X + sinAngle * original.Z * translation.Y);
        this.Elements[2] = 0f;
        this.Elements[6] = 0f;
        this.Elements[10] = cosAngle;
        this.Elements[14] = oneMinusCosAngle * original.X * translation.Z - sinAngle * original.Y * translation.Y;
        this.Elements[3] = 0f;
        this.Elements[7] = 0f;
        this.Elements[11] = translation.Z;
        this.Elements[15] = 1f;

        return this;
    }

    // 使用该矩阵将原始坐标映射到目标坐标系的方法
    public Point MapToTargetSystem(Vector3 point)
    {
        Vector4 transformed = new Vector4(point, 1f); // 将三维坐标加上w分量
        Vector4 result = Vector4.Transform(transformed, this); // 应用矩阵变换
        return new Point((float)result.X / result.W, (float)result.Y / result.W, (float)result.Z / result.W); // 返回新的坐标并去掉w分量
    }
}

// 使用示例
Point original = new Point(1, 2, 3);
Point target = new Point(4, 5, 6);
Matrix4x4 transformationMatrix = new Matrix4x4().ComputeTransformation(original, target);

Vector3 otherPointOriginal = new Vector3(7, 8, 9);
Point mappedPoint = transformationMatrix.MapToTargetSystem(otherPointOriginal);