以下均为MFC工程代码
代码一：简单实现
void CGeotranView::Onyuantu() {// 原图，画三角形CDC *pDC=GetDC();pDC->MoveTo(100,100);pDC->LineTo(200,50);pDC->LineTo(200,150);pDC->LineTo(100,100);ReleaseDC(pDC);}void CGeotranView::Ontranslation() {// 平移 tx=50,ty=60CDC *pDC=GetDC();int tx=50,ty=60;pDC->MoveTo(100+tx,100+ty);pDC->LineTo(200+tx,50+ty);pDC->LineTo(200+tx,150+ty);pDC->LineTo(100+tx,100+ty);ReleaseDC(pDC);}void CGeotranView::Onrotation() {// 旋转, 角度sita=30度CDC *pDC=GetDC();double sita=30;double hudu=sita*3.14159/180;pDC->MoveTo(int(100*cos(hudu)-100*sin(hudu)),int(100*sin(hudu)+100*cos(hudu)));pDC->LineTo(int(200*cos(hudu)-50*sin(hudu)),int(200*sin(hudu)+50*cos(hudu)));pDC->LineTo(int(200*cos(hudu)-150*sin(hudu)),int(200*sin(hudu)+150*cos(hudu)));pDC->LineTo(int(100*cos(hudu)-100*sin(hudu)),int(100*sin(hudu)+100*cos(hudu)));ReleaseDC(pDC);}void CGeotranView::Onscaling() {// 缩放 sx=2,sy=3int sx=2,sy=3;CDC *pDC=GetDC();pDC->MoveTo(100*sx,100*sy);pDC->LineTo(200*sx,50*sy);pDC->LineTo(200*sx,150*sy);pDC->LineTo(100*sx,100*sy);ReleaseDC(pDC);}
代码二：新的点的坐标计算通过函数实现
POINT translationPoint(POINT point,int tx,int ty){POINT newpoint;newpoint.x=point.x+tx;newpoint.y=point.y+ty;return newpoint;}POINT rotationPoint(POINT point,double sita){POINT newpoint;double hudu=sita*3.14159/180;newpoint.x=(int)(point.x*cos(hudu)-point.y*sin(hudu));newpoint.y=(int)(point.x*sin(hudu)+point.y*cos(hudu));return newpoint;}POINT scalingPoint(POINT point,int sx,int sy){POINT newpoint;newpoint.x=point.x*sx;newpoint.y=point.y*sy;return newpoint;}void CGeotranView::Onyuantu2() {POINT point1,point2,point3;point1.x=200;point1.y=200;point2.x=300;point3.y=150;point3.x=300;point2.y=250;// 原图，画三角形CDC *pDC=GetDC();pDC->MoveTo(point1);pDC->LineTo(point2);pDC->LineTo(point3);pDC->LineTo(point1);ReleaseDC(pDC);}void CGeotranView::Ontranslation2() {POINT point1,point2,point3;point1.x=200;point1.y=200;point2.x=300;point3.y=150;point3.x=300;point2.y=250;// 平移 tx=50,ty=60CDC *pDC=GetDC();int tx=50,ty=60;pDC->MoveTo(translationPoint(point1,tx,ty));pDC->LineTo(translationPoint(point2,tx,ty));pDC->LineTo(translationPoint(point3,tx,ty));pDC->LineTo(translationPoint(point1,tx,ty));ReleaseDC(pDC);}void CGeotranView::Onrotation2() {POINT point1,point2,point3;point1.x=200;point1.y=200;point2.x=300;point3.y=150;point3.x=300;point2.y=250;// 旋转, 角度sita=30度CDC *pDC=GetDC();double sita=30;pDC->MoveTo(rotationPoint(point1,sita));pDC->LineTo(rotationPoint(point2,sita));pDC->LineTo(rotationPoint(point3,sita));pDC->LineTo(rotationPoint(point1,sita));ReleaseDC(pDC);}void CGeotranView::Onscaling2() {POINT point1,point2,point3;point1.x=200;point1.y=200;point2.x=300;point3.y=150;point3.x=300;point2.y=250;// 缩放 sx=2,sy=2int sx=2,sy=2;CDC *pDC=GetDC();pDC->MoveTo(scalingPoint(point1,sx,sy));pDC->LineTo(scalingPoint(point2,sx,sy));pDC->LineTo(scalingPoint(point3,sx,sy));pDC->LineTo(scalingPoint(point1,sx,sy));ReleaseDC(pDC);}
