dglsview.cpp

演示道格拉斯数据压缩算法

// DglsView.cpp : implementation of the CDglsView class
//

#include "stdafx.h"
#include "Dgls.h"
//#include "afxtempl.h"//链表头文件
#include "math.h"//数学公式
#include "DglsDoc.h"
#include "DglsView.h"
#include "Limendialog.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CDglsView

IMPLEMENT_DYNCREATE(CDglsView, CView)

BEGIN_MESSAGE_MAP(CDglsView, CView)
	//{{AFX_MSG_MAP(CDglsView)
	ON_COMMAND(ID_EDIT_INPUTLIMEN, OnEditInputlimen)
	ON_COMMAND(ID_COLOR, OnColor)
	ON_COMMAND(ID_LXLINE, OnLxline)
	ON_UPDATE_COMMAND_UI(ID_LXLINE, OnUpdateLxline)
	ON_WM_LBUTTONDOWN()
	ON_WM_MOUSEMOVE()
	ON_WM_RBUTTONDOWN()
	ON_WM_LBUTTONDBLCLK()
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CDglsView construction/destruction

CDglsView::CDglsView()
{
	// TODO: add construction code here

}

CDglsView::~CDglsView()
{
}

BOOL CDglsView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CDglsView drawing

void CDglsView::OnDraw(CDC* pDC)
{
	CDglsDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	//CPaintDC dc(this);
	//dc.SetROP2(R2_NOT);
	//CRect Recto;
	//获取客户区尺寸
	//GetClientRect(&Recto);
    //pDC->SetViewportOrg(0,Recto.Height);
	///pDC->SetViewportOrg(0,400);
	//pDC->Ellipse(20,20,100,100);//2*Limen,2*Limen);
	pDC->TextOut(20,10,"左边两条线段为阈值参考线，第一条长100，第二条长50");
	pDC->TextOut(20,35,"先点击画线菜单按钮,画曲线段,然后通过道格拉斯压缩菜单设置颜色和阈值");
	pDC->MoveTo(30,110);
	pDC->LineTo(30,210);
	pDC->MoveTo(50,160);
	pDC->LineTo(50,210);
    int index;
	index=pDoc->m_MLine.GetSize ();
	while(index--)
	pDoc->GetMLine (index)->My(pDC);
	// TODO: add draw code for native data here
}

/////////////////////////////////////////////////////////////////////////////
// CDglsView printing

BOOL CDglsView::OnPreparePrinting(CPrintInfo* pInfo)
{
	// default preparation
	return DoPreparePrinting(pInfo);
}

void CDglsView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add extra initialization before printing
}

void CDglsView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add cleanup after printing
}

/////////////////////////////////////////////////////////////////////////////
// CDglsView diagnostics

#ifdef _DEBUG
void CDglsView::AssertValid() const
{
	CView::AssertValid();
}

void CDglsView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}

CDglsDoc* CDglsView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CDglsDoc)));
	return (CDglsDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CDglsView message handlers

void CDglsView::OnEditInputlimen() 
{
	// TODO: Add your command handler code here
	CLimenDialog dlg;//定义一个对话框对象
	dlg.m_nLimen =50;//设置编辑框初始值
	if(dlg.DoModal()==IDOK)//显示对话框
	{
	   CClientDC pDC(this);
	   CDglsDoc* pDoc = GetDocument();
       ASSERT_VALID(pDoc);
	   CPen newpen(PS_SOLID,1,color);//设置颜色
	   CPen *old=pDC.SelectObject(&newpen);
       Limen=dlg.m_nLimen ;//接受并存储编辑框数据
	   int first=0,last=num-1; //first为第一点，last为第二点
	   dgls(first,last,Limen);
	  
	}
}

void CDglsView::OnColor() 
{
	// TODO: Add your command handler code here
	CColorDialog ColorDlg;
	if(ColorDlg.DoModal())
	{
     color=ColorDlg.GetColor();
	}
}

void CDglsView::OnLxline() 
{
	// TODO: Add your command handler code here
	m_nlxline=true;
    start=0;
	flag=1;

}

void CDglsView::OnUpdateLxline(CCmdUI* pCmdUI) 
{
	// TODO: Add your command update UI handler code here
	pCmdUI->SetCheck(m_nlxline);
}
void CDglsView::OnLButtonDown(UINT nFlags, CPoint point) //鼠标左击时执行
{
	// TODO: Add your message handler code here and/or call default
  if(flag!=1)
  {
	  MessageBox("请先选择画线按钮!","警告");
  }
  else
  {
    if(start==false)
	{
		m_Start=point;
		m_End=point;
		SetCapture();//设置鼠标
		SetCursor(m_Hcursor);//光标句柄
		start=true;
		if(m_nlxline)//如果画连续执行，设置坐标点数组，保存坐标位置
		{
          points=new CPoint[100];
		  points[0]=point;
		  num=1;
		}
	}
	else
	{
		m_End=point;
		CClientDC pDC(this);
		CDglsDoc* pDoc = GetDocument();
     	ASSERT_VALID(pDoc);
		if(m_nlxline)
		{
			pDC.MoveTo(m_Start);
			pDC.LineTo(m_End);
			m_Start=point;
			start=true;//继续执行画线第二步
			points[num]=point;
			num++;
		}
	}
  }
	CView::OnLButtonDown(nFlags, point);
}

void CDglsView::OnMouseMove(UINT nFlags, CPoint point) //鼠标移动时执行 
{
	// TODO: Add your message handler code here and/or call default
	if(start==true)
	{
		CClientDC dc(this);
		dc.SetROP2(R2_NOT);
		SetCursor(m_Hcursor);
		if(m_nlxline)
		{
           dc.MoveTo(m_Start);
		   dc.LineTo(m_End);//用反色擦除上条直线
		   dc.MoveTo(m_Start);
		   dc.LineTo(point);//重画直线
		}
		m_End=point;
	}
	CView::OnMouseMove(nFlags, point);
}

void CDglsView::OnRButtonDown(UINT nFlags, CPoint point) //鼠标右击时执行
{
	// TODO: Add your message handler code here and/or call default
	CClientDC dc(this);
	dc.SetROP2(R2_NOT);
	SetCursor(m_Hcursor);
	if(m_nlxline && start==true)
		{
			int nChoice=AfxMessageBox("是否保留该线?",MB_YESNO|MB_ICONQUESTION);
			                                     //调用消息对话框
			if(nChoice==IDYES)                   //回答是时
			{
				points[num]=point;
				num++;
				CDglsDoc* pDoc=GetDocument();
				ASSERT_VALID(pDoc);
				int* pointx=new int[num];
				int* pointy=new int[num];
				for(int i=0;i<num;i++)
				{
					pointx[i]=points[i].x;
					pointy[i]=points[i].y;
				}
				pDoc->AddMLine(pointx,pointy,num,0);//保存点
			}
			else            //回答否时
			{
				for(int i=1;i<num;i++)
				{
					dc.MoveTo(points[i-1]);
					dc.LineTo(points[i]);
				}
				dc.MoveTo(points[num-1]);
				dc.LineTo(point);
			}
		}
	start =false;
	ReleaseCapture();//释放鼠标
	ClipCursor(NULL);//还原鼠标
	CView::OnRButtonDown(nFlags, point);
}

void CDglsView::OnLButtonDblClk(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	MessageBox("未设置双击功能!","警告");
	CView::OnLButtonDblClk(nFlags, point);
}

void CDglsView::dgls(int first, int last, float dd)//dgls,dd为阈值
{
       int* pointx=new int[num];
	   int* pointy=new int[num];
	   for(int i=0;i<num;i++)
	   {
			pointx[i]=points[i].x;
			pointy[i]=points[i].y;
	   }
	   //first为第一点，last为第二点
	   CClientDC pDC(this);
	   CDglsDoc* pDoc = GetDocument();
       ASSERT_VALID(pDoc);
	   CPen newpen(PS_SOLID,1,color);//设置颜色
	   CPen *old=pDC.SelectObject(&newpen);
	   float A,B,C;
	   A=pointy[last]-pointy[first];//y2-y1
	   B=pointx[first]-pointx[last];//x1-x2
	   C=pointx[last]*pointy[first]-pointx[first]*pointy[last];//x2*y1-x1*y2
	  float d[100];//距离矩阵
	  float maxd=0;
	  int k=0;//标记最大距离点
	  for(int j=first+1;j<last;j++)
	  {
		  d[j]=abs(A*pointx[j]+B*pointy[j]+C)/sqrt(A*A+B*B);
	      if(maxd<d[j])
		  {
			  maxd=d[j];
			  k=j;
		  }
	  }
	  if(maxd<=dd)
	  {
	    pDC.MoveTo(pointx[first],pointy[first]);
	    pDC.LineTo(pointx[last],pointy[last]);
	  }	 
	  else
	  {    
		   dgls(first,k,Limen);
		   dgls(k,last,Limen);   
	  }
}