pointthredlg.cpp

人民邮电出版社的——Visual C++数字图像处理典型算法及实现（源码） 希望大家能用上

// PointThreDlg.cpp : implementation file
//

#include "stdafx.h"
#include "LineTrans.h"
#include "PointThreDlg.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CPointThreDlg dialog


CPointThreDlg::CPointThreDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CPointThreDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CPointThreDlg)
	m_bThre = 0;
	//}}AFX_DATA_INIT
}


void CPointThreDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CPointThreDlg)
	DDX_Text(pDX, IDC_EDIT_THRE, m_bThre);
	DDV_MinMaxByte(pDX, m_bThre, 0, 255);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CPointThreDlg, CDialog)
	//{{AFX_MSG_MAP(CPointThreDlg)
	ON_EN_KILLFOCUS(IDC_EDIT_THRE, OnKillfocusEDITThre)
	ON_WM_LBUTTONDOWN()
	ON_WM_LBUTTONUP()
	ON_WM_MOUSEMOVE()
	ON_WM_PAINT()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CPointThreDlg message handlers

BOOL CPointThreDlg::OnInitDialog() 
{
	CDialog::OnInitDialog();
	
	CWnd* pWnd = GetDlgItem(IDC_COORD);	
	pWnd->GetClientRect(m_MouseRect);
	pWnd->ClientToScreen(&m_MouseRect);
	
	CRect rect;
	GetClientRect(rect);
	ClientToScreen(&rect);	
	m_MouseRect.top -= rect.top;
	m_MouseRect.left -= rect.left;
	
	// 设置接受鼠标事件的有效区域
	m_MouseRect.top += 25;
	m_MouseRect.left += 10;
	m_MouseRect.bottom = m_MouseRect.top + 255;
	m_MouseRect.right = m_MouseRect.left + 256;
	
	m_bIsDraging = FALSE;

	return TRUE;
}

void CPointThreDlg::OnKillfocusEDITThre() 
{
	UpdateData(TRUE);
	InvalidateRect(m_MouseRect, TRUE);
}

void CPointThreDlg::OnLButtonDown(UINT nFlags, CPoint point) 
{
	// 当用户单击鼠标左键开始拖动	
	// 判断是否在有效区域中
	if(m_MouseRect.PtInRect(point))
	{
		if (point.x == (m_MouseRect.left + m_bThre))
		{
			m_bIsDraging = TRUE;
			::SetCursor(::LoadCursor(NULL, IDC_SIZEWE));
		}
	}
	
	CDialog::OnLButtonDown(nFlags, point);
}

void CPointThreDlg::OnLButtonUp(UINT nFlags, CPoint point) 
{
	// 当用户释放鼠标左键停止拖动
	if (m_bIsDraging)
	{
		m_bIsDraging = FALSE;
	}
	
	CDialog::OnLButtonUp(nFlags, point);
}

void CPointThreDlg::OnMouseMove(UINT nFlags, CPoint point) 
{
	// 判断当前光标是否在绘制区域
	if(m_MouseRect.PtInRect(point))
	{
		if (m_bIsDraging)
		{		
			m_bThre = (BYTE) (point.x - m_MouseRect.left);		// 更改阈值
			::SetCursor(::LoadCursor(NULL, IDC_SIZEWE));
	
			UpdateData(FALSE);
			InvalidateRect(m_MouseRect, TRUE);
		}
		else if (point.x == (m_MouseRect.left + m_bThre))
		{
			::SetCursor(::LoadCursor(NULL, IDC_SIZEWE));
		}
	}
	
	CDialog::OnMouseMove(nFlags, point);
}

void CPointThreDlg::OnPaint() 
{
	CString str;

	CPaintDC dc(this);

	CWnd* pWnd = GetDlgItem(IDC_COORD);
	CDC* pDC = pWnd->GetDC();
	pWnd->Invalidate();
	pWnd->UpdateWindow();	
	pDC->Rectangle(0,0,330,300);
	
	// 创建画笔对象
	CPen* pPenRed = new CPen;		// 红色画笔	
	pPenRed->CreatePen(PS_SOLID,2,RGB(255,0,0));
	CPen* pPenBlue = new CPen;		// 蓝色画笔
	pPenBlue->CreatePen(PS_SOLID,2,RGB(0,0, 255));	
	CPen* pPenGreen = new CPen;		// 创建画笔对象
	pPenGreen->CreatePen(PS_DOT,1,RGB(0,255,0));
	
	// 选中当前红色画笔，并保存以前的画笔
	CGdiObject* pOldPen = pDC->SelectObject(pPenRed);
	
	pDC->MoveTo(10,10);				// 绘制坐标轴	
	pDC->LineTo(10,280);			// 垂直轴	
	pDC->LineTo(320,280);			// 水平轴
	str.Format("0");
	pDC->TextOut(10, 281, str);		// 写坐标	
	str.Format("255");
	pDC->TextOut(265, 281, str);
	pDC->TextOut(11, 25, str);
	
	// 绘制X轴箭头
	pDC->LineTo(315,275);
	pDC->MoveTo(320,280);
	pDC->LineTo(315,285);
	
	// 绘制X轴箭头
	pDC->MoveTo(10,10);
	pDC->LineTo(5,15);
	pDC->MoveTo(10,10);
	pDC->LineTo(15,15);
	
	// 更改成绿色画笔
	pDC->SelectObject(pPenGreen);	
	
	// 绘制窗口阈值线
	pDC->MoveTo(m_bThre + 10, 25);
	pDC->LineTo(m_bThre + 10, 280);
	
	// 更改成蓝色画笔
	pDC->SelectObject(pPenBlue);	
	
	// 绘制坐标值
	str.Format("%d", m_bThre);
	pDC->TextOut(m_bThre + 10, 281, str);
	
	// 绘制用户指定的窗口（注意转换坐标系）
	pDC->MoveTo(10, 280);
	pDC->LineTo(m_bThre + 10, 280);
	pDC->LineTo(m_bThre + 10, 25);
	pDC->LineTo(265, 25);
	
	// 恢复以前的画笔
	pDC->SelectObject(pOldPen);	
	
	// 绘制边缘
	pDC->MoveTo(10,25);
	pDC->LineTo(265,25);
	pDC->LineTo(265,280);
	
	delete pPenRed;
	delete pPenBlue;
	delete pPenGreen;
}