下面程序，容易看出行主序在坐标点变换中效率更高 

#include <WINDOWS.H>
#include <IOSTREAM>

using namespace std;



enum MatrixIndex
{
	Xx, Xy, Xz, Xi,	   // X方向
	Yx, Yy, Yz, Yi,    // y方向
	Zx, Zy, Zz, Zi,    // z方向
	Tx, Ty, Tz, Ii,    // 移动
};


struct POINT3D
{
	double x, y, z;
	POINT3D() { ZeroMemory(this, sizeof(POINT3D)); }
	POINT3D(double tx, double ty, double tz) {x = tx; y = ty; z = tz;}
	void Modify(float *pglM)
	{
		double x1=0.0, y1=0.0, z1=0.0;
		x1 = x*pglM[Xx] + y*pglM[Yx] + z*pglM[Zx] + pglM[Tx];
		y1 = x*pglM[Xy] + y*pglM[Yy] + z*pglM[Zy] + pglM[Ty];
		z1 = x*pglM[Xz] + y*pglM[Yz] + z*pglM[Zz] + pglM[Tz];
		x = x1;
		y = y1;
		z = z1;
	}
	void ModifyT(float *pglM)
	{
		double x1=0.0, y1=0.0, z1=0.0;
		x1 = x*(*pglM++); x1 += y*(*pglM++); x1 += z*(*pglM++); x1 += (*pglM++);
		y1 = x*(*pglM++); y1 += y*(*pglM++); y1 += z*(*pglM++); y1 += (*pglM++);
		z1 = x*(*pglM++); z1 += y*(*pglM++); z1 += z*(*pglM++); z1 += (*pglM++);
		x = x1;
		y = y1;
		z = z1;
	}
};

void main()
{
	// 列主序
	float M[16] = 
	{
		1.0, 0.0, 0.0, 0.0,
		0.0, 1.0, 0.0, 0.0,
		0.0, 0.0, 1.0, 0.0,
		2.0, 2.0, 2.0, 1.0   // Trans
	};

	POINT3D pt(1.0, 2.0, 3.0);
	pt.Modify(M);
	cout << pt.x << " " << pt.y << " " << pt.z << endl;


	// 行主序
	float MT[16] = 
	{                  //Trans
		1.0, 0.0, 0.0, 2.0,
		0.0, 1.0, 0.0, 2.0,
		0.0, 0.0, 1.0, 2.0,
		0.0, 0.0, 0.0, 1.0
	};
	POINT3D pt2(1.0, 2.0, 3.0);
	pt2.ModifyT(MT);
	cout << pt2.x << " " << pt2.y << " " << pt2.z << endl;
}