C写的填充算法源码 算法可是在编程中可是非常重要的 大家可以参考一下这个代码

// 填充Dlg.cpp : implementation file
//

#include "stdafx.h"
#include "填充.h"
#include "填充Dlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About

class CAboutDlg : public CDialog
{
public:
	CAboutDlg();

// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA

	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL

// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};

CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
	//{{AFX_DATA_INIT(CAboutDlg)
	//}}AFX_DATA_INIT
}

void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CAboutDlg)
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyDlg dialog

CMyDlg::CMyDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CMyDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CMyDlg)
		// NOTE: the ClassWizard will add member initialization here
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
	num = 0;
	col = RGB(0,0,0);
	ldb = FALSE;
	step = 0;
}

void CMyDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CMyDlg)
		// NOTE: the ClassWizard will add DDX and DDV calls here
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CMyDlg, CDialog)
	//{{AFX_MSG_MAP(CMyDlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_BUTTON4, OnButton4)
	ON_BN_CLICKED(IDC_BUTTON1, OnButton1)
	ON_WM_LBUTTONDOWN()
	ON_WM_LBUTTONUP()
	ON_WM_MOUSEMOVE()
	ON_BN_CLICKED(IDC_BUTTON2, OnButton2)
	ON_BN_CLICKED(IDC_BUTTON3, OnButton3)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyDlg message handlers

BOOL CMyDlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	
	// TODO: Add extra initialization here
	CPaintDC dc(this);
	pic.CreateCompatibleDC(&dc);
	CBitmap * bp1,*obp1;
	bp1 = new CBitmap;
	bp1->LoadBitmap(IDB_B);
	obp1 = pic.SelectObject(bp1);
	obp1->DeleteObject();

	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CMyDlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}

// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.

void CMyDlg::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
	if (IsIconic())
	{

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
	CDC mdc;
	CBitmap bp,*ob;
	bp.LoadBitmap(IDB_B);
	mdc.CreateCompatibleDC(GetDC());
	ob = mdc.SelectObject(&bp);
	mdc.BitBlt(0,0,520,330,&pic,0,0,SRCCOPY);
	mdc.MoveTo(mx[0],my[0]);
	for(int i = 1;i<num;i++){
		mdc.LineTo(mx[i],my[i]);
	}
	if(step!=1){
		mdc.LineTo(mx[0],my[0]);
	}

	CDC * dc1;
	CWnd * wd1;
	wd1 = this->GetDlgItem(IDC_S);
	dc1 = wd1->GetDC();
	dc1->BitBlt(1,1,517,327,&mdc,0,0,SRCCOPY);
	mdc.SelectObject(ob);
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CMyDlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

void CMyDlg::OnButton4() 
{
	// TODO: Add your control notification handler code here
	OnOK();
}

void CMyDlg::OnButton1() 
{
	// TODO: Add your control notification handler code here
	if(step == 1){
		step = 0;
		SetDlgItemText(IDC_BUTTON1,"画多边形");
		Invalidate(FALSE);
	}
	else{
		num = 0;
		step = 1;
		ldb = FALSE;
		SetDlgItemText(IDC_BUTTON1,"绘制完毕");

		CDC mdc;
		CBitmap bmp,*obp;
		bmp.LoadBitmap(IDB_B);
		mdc.CreateCompatibleDC(GetDC());
		obp = mdc.SelectObject(&bmp);
		pic.BitBlt(0,0,520,330,&mdc,0,0,SRCCOPY);
		mdc.SelectObject(obp);
		Invalidate(FALSE);
	}
}

void CMyDlg::OnLButtonDown(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	if(step == 1&&point.x>11&&point.x<529&&point.y>11&&point.y<339){
		if(num<49){
			ldb = TRUE;
			if(!num){
				mx[num] = point.x-12;
				my[num] = point.y-12;
				num ++;
			}
			num ++;
//			Invalidate(FALSE);
		}
	}
	CDialog::OnLButtonDown(nFlags, point);
}

void CMyDlg::OnLButtonUp(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	if(ldb){
		ldb = FALSE;
		mx[num-1] = point.x - 12;
		my[num-1] = point.y - 12;
		Invalidate(FALSE);
	}
	CDialog::OnLButtonUp(nFlags, point);
}

void CMyDlg::OnMouseMove(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	if(ldb){
		mx[num-1] = point.x - 12;
		my[num-1] = point.y - 12;
		Invalidate(FALSE);
	}
	CDialog::OnMouseMove(nFlags, point);
}

void CMyDlg::OnButton2() 
{
	// TODO: Add your control notification handler code here
	CColorDialog ccd(col);
	if(ccd.DoModal()==IDOK){
		col = ccd.GetColor();
	}
}

void CMyDlg::OnButton3() 
{
	// TODO: Add your control notification handler code here
	step = 0;
	ldb = FALSE;
	SetDlgItemText(IDC_BUTTON1,"画多边形");
	if(num < 2){
		MessageBox("尚未绘制多边形！");
		return;
	}
	int i = 0,j,k;
	int b,e;
	float d,fd;
	for(i = 0;i<num;i++){//对各条边进行处理
		b = my[i];
		e = my[(i+1)%num];
		d = float(mx[i]-mx[(i+1)%num])/(my[i]-my[(i+1)%num]);
		fd = float(mx[i]);
		if(b>e){
			j = b;
			b = e;
			e = j;
			fd = float(mx[(i+1)%num]);
		}
		for(j = b;j<e;j++){//处理一条边上各个点
//			if(j == my[i]){
//				k = mx[i];
//			}
//			else{
//				k = int(float((j-my[i])*(my[(i+1)%num]-my[i]))/float(mx[(i+1)%num]-mx[i])+float(mx[i])+0.5f);
//			}
			k = int(fd+(j-b)*d+0.5f);
			for(;k<518;k++){
				if(pic.GetPixel(k,j)==col){
					pic.SetPixel(k,j,RGB(255,255,255));
				}
				else{
					pic.SetPixel(k,j,col);
				}
			}
		}
	}
	Invalidate(FALSE);
}