Eigen库旋转矩阵和平移向量组成齐次变换矩阵旋转矩阵和平移向量组成齐次变换矩阵block操作Blockoperati

$3\times 3$ 旋转矩阵 $r$ 和 $3\times 1$ 平移向量 $t$ 组成 $4\times 4$ 齐次变换矩阵 $trans$

Block operation	Version constructing a dynamic-size block expression	Version constructing a fixed-size block expression
Block of size (p,q), starting at (i,j)	`matrix.block(i,j,p,q)`	`matrix.block<p,q>(i,j);`

方法

Matrix3f r; // rotation matrix
Vector3f t; // translation vector

Matrix4f trans; // transformation matrix
trans.setIdentity();   // set to identity
trans.block<3,3>(0,0) = r; // first 3x3 block set to rotation matrix
trans.block<3,1>(0,3) = t; // fourth column set to translation vector

测试

#include <iostream>
#include <exception>
#include <Eigen/Eigen>

using namespace std;
using namespace Eigen;

constexpr float pi = 3.14f;

int main(int argc, char **argv)
{
	Matrix3f r; // rotation matrix
	Vector3f t; // translation vector
	AngleAxisf rot_x (pi/4, Vector3f(1, 0, 0));
	r = rot_x.matrix();
	t = {0.0f, 0.5f, 0.0f};

	/* construct transformation matrix with rotaion matirx and translation vector */
	Matrix4f trans; // transformation matrix
	trans.setIdentity();   // set to identity
	trans.block<3,3>(0,0) = r; // first 3x3 block set to rotation matrix
	trans.block<3,1>(0,3) = t; // fourth column set to translation vector

	/* print */
	cout << "rotaiton matrix: " << endl << r.format({3}) << endl;
	cout << "translation vector: " << endl << t.format({3}) << endl;
	cout << "transformation matrix: " << endl << trans.format({3}) << endl;

    return EXIT_SUCCESS;
}

输出

参考

[1] Block operations

Eigen库 旋转矩阵和平移向量组成齐次变换矩阵

方法

测试

输出

参考

Eigen库旋转矩阵和平移向量组成齐次变换矩阵