矩阵运算Matrix2D

#include "StdAfx.h" #include ".\matrix2d.h" //dx和dy用来指定x和y方向的平移量，若dx = dy = 0，则： //(1) 当m21 = m12 = 0，m11 = -1，m22 = 1时，有x*= -x，y*= y，产生与y轴对称的反射图形； //(2) 当m21 = m12 = 0，m11 = 1，m22 = -1时，有x*= x，y*= -y，产生与x轴对称的反射图形； //(3) 当m21 = m12 = 0，m11 = m22 = -1时，有x*= -x，y*= -y，产生与原点对称的反射图形； //(4) 当m21 = m12 = 1，m11 = m22 = 0时，有x*= y，y*= x，产生与直线y = x对称的反射图形； //(5) 当m21 = m12 = -1，m11 = m22 = 0时，有x*= -y，y*= -x，产生与直线y = -x对称的反射图形； CMatrix2D::CMatrix2D(void) { Reset(); } CMatrix2D::~CMatrix2D(void) { } // set identity matrix elements void CMatrix2D::Reset(void) { SetMatrix(1.0, 0.0, 0.0, 1.0, 0.0, 0.0); } void CMatrix2D::Rotate(double thetaAngle)//旋转变换 { double v; v=sin(thetaAngle); m[1]=v; m[2]=-v; v=cos(thetaAngle); m[0]=v; m[3]=v; double dx=m[4]; double dy=m[5]; m[4]=(1-cos(thetaAngle))*dx+dy*sin(thetaAngle); m[5]=(1-cos(thetaAngle))*dy-dx*sin(thetaAngle); } void CMatrix2D::Translate(double dx, double dy)//平移变换 { m[4]+=dx; m[5]+=dy; } void CMatrix2D::Shear(double shearX, double shearY)//错切变换 { m[2]=shearX; m[1]=shearY; } //当scaleX==scaleY时等比例缩放，0<scaleX<1时缩小，scaleX>1时放大 void CMatrix2D::Scale(double scaleX, double scaleY)//比例缩放 { m[0]*=scaleX; m[3]*=scaleY; } void CMatrix2D::RotateAt(double centerX, double centerY, double thetaAngle) { Translate(-centerX,-centerY); Rotate(thetaAngle); Translate(centerX,centerY); } // | a1 a2 | | m[0] m[1] | //Matrix = | b1 b2 | = | m[2] m[3] | // | c1 c2 | | m[4] m[5] | void CMatrix2D::SetMatrix(double a1, double a2, double b1, double b2, double c1, double c2) { m[0]=a1; m[1]=a2; m[2]=b1; m[3]=b2; m[4]=c1; m[5]=c2; } void CMatrix2D::SetMatrix(double *pm) { memcpy(m,pm,sizeof(double)*6); } void CMatrix2D::operator=(CMatrix2D& md) { memcpy(m,md.m,sizeof(double)*6); } void CMatrix2D::Exchange(double& x, double& y, BOOL bUndo) { double x0=x; double y0=y; if(!bUndo) { x=x0*m[0] + y0*m[2] + m[4]; y=x0*m[1] + y0*m[3] + m[5]; } else { x=(m[3]*(x0-m[4]) + m[2]*(m[5]-y0))/(m[0]*m[3]-m[1]*m[2]); y=(m[1]*(x0-m[4]) + m[0]*(m[5]-y0))/(m[0]*m[3]-m[1]*m[2]); y*=-1; } }