MFC-VIEW 缩放平移

80 阅读 0 评论 53 点赞

我是靠谱客的博主明理期待，最近开发中收集的这篇文章主要介绍MFC-VIEW 缩放平移，觉得挺不错的，现在分享给大家，希望可以做个参考。

概述

1. 图形类中有数据成员，开始点，结束点，一个包含可参与矩阵运算的点数组

2. 使用一个矩阵，调用矩阵的设置函数，读入图形类中点数组的地址

3. 为矩阵输入平移、缩放参数

4. 运算矩阵并把数据保存到图形类中的点数组

5. 绘图时，取点数组中数据绘图，

public:
CPoint pt1;
CPoint pt0;

CPoint p[3];
BOOL bLBDown ;//左键按下状态初始化

bool bMWDown;
int nCount ;//顶点计数器初始化

double m_Scale;
CPoint m_ptCur;

CLine2 line2 ;

CTransfrom2 Transfrom ;

void CTestView::OnDraw(CDC* pDC)
{
   CTestDoc* pDoc = GetDocument();
   ASSERT_VALID(pDoc);
   // TODO: add draw code for native data here

   if (!pDoc)
       return;

   // TODO: 在此处为本机数据添加绘制代码
   //DoubleBuffer(pDC);

line2.Draw(pDC);

   CString str;
   str.Format("m_Scale %0.2f m_ptCur x=%d,y=%d", m_Scale , m_ptCur.x,   m_ptCur.y);
   pDC->TextOut(500, 50, str);//输出顶点实时坐标

}

void CTestView::OnMouseMove(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default

       m_ptCur = point ;

   CView::OnMouseMove(nFlags, point);
}

void CTestView::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
bLBDown = true;//鼠标左键按下，记为真

CView::OnLButtonDown(nFlags, point);
}

void CTestView::OnLButtonUp(UINT nFlags, CPoint point)
{
   // TODO: Add your message handler code here and/or call default
   bLBDown = false;//鼠标左键抬起，记为假
   CView::OnLButtonUp(nFlags, point);
}

BOOL CTestView::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
{
   // TODO: Add your message handler code here and/or call default
   int nDelta = zDelta;

   switch (nDelta)
{
case -120:

       m_Scale += 0.1;

       bMWDown = true ;

       if (m_Scale >= 1.0)   m_Scale = 1.0;


break;

case 120:

       m_Scale -= 0.1;

bMWDown = false ;

       if (m_Scale <= 0.1) m_Scale = 0.1;


break;
default: break;
}

   CPoint tmp = m_ptCur ;

       CDC* pDC = GetDC();
       pDC->DPtoLP(&tmp);
       ReleaseDC(pDC);

       CP2 *ptCen = new CP2;
       ptCen-> x = (double)tmp.x ;
       ptCen-> y = (double)tmp.y ;


       Transfrom.SetMatrix(line2.P ,2);

       if(bMWDown)
       {
           Transfrom.Scale(0.5f, 0.5f ,*ptCen);
       }
       else
       {
           Transfrom.Scale(2.0f, 2.0f ,*ptCen);
       }

       delete ptCen ;

   Invalidate();

return true ;

//return CView::OnMouseWheel(nFlags, zDelta, pt);
}

void CTestView::OnMButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
CDC* pDC = GetDC();
pDC->DPtoLP(&point);
pt0 = point ;
CView::OnMButtonDown(nFlags, point);
}

void CTestView::OnMButtonUp(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
CDC* pDC = GetDC();
pDC->DPtoLP(&point);
pt1 = point ;
double x = pt1.x - pt0.x ;
double y = pt1.y - pt0.y ;

   Transfrom.SetMatrix(line2.P ,2);
   Transfrom.Translate(x,y);

Invalidate();
CView::OnMButtonUp(nFlags, point);
}

----------------------------------------------------------------------------------------

pDC->TextOut(0,0,_T("SetWorldTransform!"));
pDC->MoveTo(100,50); pDC->LineTo(200,50);

   XFORM xform;
   ZeroMemory(&xform, sizeof(XFORM));
   xform.eM11 = 1;
   xform.eM22 = 1;
   xform.eDx = 100;
   xform.eDy = 100;

   HDC hDC = pDC->GetSafeHdc();
   SetGraphicsMode(hDC , GM_ADVANCED);
   pDC->SetMapMode(MM_ANISOTROPIC);
   SetWorldTransform(hDC, &xform);
   pDC->TextOut(0,0,_T("SetWorldTransform!Translate!"));//平移到(100，100)
   pDC->MoveTo(100,50); pDC->LineTo(200,50);

   xform.eM11 = 5.0f;
   xform.eM22 = 5.0f;
   SetWorldTransform(hDC, &xform);
   pDC->TextOut(0,0,_T("SetWorldTransform!Scale!"));//放大
   pDC->MoveTo(100,50); pDC->LineTo(200,50);


   xform.eM11 = 0.866f;
   xform.eM22 = 0.866f;
   xform.eM12 = 0.5f;
   xform.eM21 = -0.5f;
   SetWorldTransform(hDC, &xform);
   pDC->TextOut(0,0,_T("SetWorldTransform!Rotate!"));//旋转30°
   pDC->MoveTo(100,50); pDC->LineTo(200,50);




   ZeroMemory(&xform, sizeof(XFORM));
   xform.eM11 = 1;
   xform.eM22 = 1;
   SetWorldTransform(hDC, &xform);//恢复默认
   SetGraphicsMode(hDC , GM_COMPATIBLE);//恢复默认
   pDC->MoveTo(100,60); pDC->LineTo(200,60);

----------------------------------------------------------------------------------------------------------

public:
   CPoint pt1;
   CPoint pt0;
   int sc;

CTestDxfView::CTestDxfView()
{
// TODO: add construction code here
sc = 5;
}

void CTestDxfView::OnDraw(CDC* pDC)
{
   CTestDxfDoc* pDoc = GetDocument();
   ASSERT_VALID(pDoc);
   // TODO: add draw code for native data here

   //取得视口矩形
   CRect rect;
   GetClientRect(&rect);
   //
   pDC->SetMapMode(MM_ANISOTROPIC);   //逻辑单元将转换为具有任意缩放轴的任意单位

   pDC->SetViewportExt   (rect.right,rect.bottom);
   pDC->SetViewportOrg(rect.right/2 + (pt1.x-pt0.x),rect.bottom/2 + (pt1.y-pt0.y));

   pDC->SetWindowExt   (rect.right*sc,-rect.bottom*sc);
   pDC->SetWindowOrg(0,0);

pDC->Rectangle(-3000,-1300,3000,1300);
pDC->Rectangle(-3000+50,-1300+50,3000-50,1300-50);

}

BOOL CTestDxfView::OnMouseWheel(UINT nFlags, short zDelta, CPoint pt)
{
// TODO: Add your message handler code here and/or call default

   switch (zDelta)
   {
   case -120:
       if (sc >= 20)
       {
           sc = 20;
       }
       else
       {
           sc += 1;
       }

       break;
   case 120:
       if (sc <= 1)
       {
           sc = 1;
       }
       else
       {
           sc -= 1;
       }

       break;
   default:
       break;
   }

   Invalidate();

   return CView::OnMouseWheel(nFlags, zDelta, pt);
}

///手动添加消息映射

ON_WM_MBUTTONDOWN()
ON_WM_MBUTTONUP()

afx_msg void OnMButtonDown(UINT nFlags, CPoint point);
afx_msg void OnMButtonUp(UINT nFlags, CPoint point);

void CTestDxfView::OnMButtonDown(UINT nFlags, CPoint point)
{
   // TODO: Add your message handler code here and/or call default
   CDC* pDC = GetDC();
   pDC->DPtoLP(&point);
   pt0 = point ;
   CView::OnMButtonDown(nFlags, point);
}

void CTestDxfView::OnMButtonUp(UINT nFlags, CPoint point)
{
   // TODO: Add your message handler code here and/or call default
   CDC* pDC = GetDC();
   pDC->DPtoLP(&point);
   pt1 = point ;
   Invalidate();
   CView::OnMButtonUp(nFlags, point);
}