treedlg.cpp

给出了分形计算生成动态树的VC＋＋源代码。生长出来的树摇曳而逼真。

// treeDlg.cpp : implementation file
//

#include "stdafx.h"
#include "tree.h"
#include "treeDlg.h"
#include <math.h>

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

//定义PI
const double PI=3.11415926/180;

/////////////////////////////////////////////////////////////////////////////
// CTreeDlg dialog

CTreeDlg::CTreeDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CTreeDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CTreeDlg)
		// 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);

	/************************************************************************/
	m_bRunning = FALSE;
	m_Interval = 10;
	m_bgColor = RGB(0, 0, 0);
	m_fgColor = RGB(0, 255, 0);
	m_C = 9;
	m_dir = TRUE;
	/************************************************************************/	
}

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

BEGIN_MESSAGE_MAP(CTreeDlg, CDialog)
	//{{AFX_MSG_MAP(CTreeDlg)
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_WM_LBUTTONDOWN()
	ON_WM_TIMER()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CTreeDlg message handlers

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

	// 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
	
	/************************************************************************/
	//获取窗口大小
	GetClientRect(&m_Rect);
	//得到物理画布
	m_DC.Attach(::GetDC(*this));
	//创建内存画布
	m_MemDC.CreateCompatibleDC(&m_DC);
	m_Bitmap.CreateCompatibleBitmap(&m_DC, m_Rect.Width(), m_Rect.Height());
	m_MemDC.SelectObject(&m_Bitmap);
	//设置画笔颜色
	m_Pen.CreatePen(PS_SOLID, 1, m_fgColor);
	m_MemDC.SelectObject(&m_Pen);
	//填充背景颜色
	m_MemDC.FillSolidRect(&m_Rect, m_bgColor);
	/************************************************************************/

	return TRUE;  
}

// 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 CTreeDlg::OnPaint() 
{
	AfxGetMainWnd()->SetWindowText("摇曳的分形树（分形频道：fractal.cn）2004    请单击窗体");
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		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
	{
		m_DC.BitBlt(0, 0, m_Rect.Width(), m_Rect.Height(), 
			&m_MemDC, 0, 0, SRCCOPY);

		CDialog::OnPaint();
	}
}

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

//单击暂停/恢复
void CTreeDlg::OnLButtonDown(UINT nFlags, CPoint point) 
{
	if (m_bRunning) {
		KillTimer(10);
		m_bRunning = FALSE;
	} else {
		SetTimer(10, m_Interval, NULL);
		m_bRunning = TRUE;
	}
	
	CDialog::OnLButtonDown(nFlags, point);
}

//定时器处理函数，在这个函数里绘制树
void CTreeDlg::OnTimer(UINT nIDEvent) 
{
	int x, y;

	x = m_Rect.Width()/2;
	y = m_Rect.Height()-50;

	//在内存画布中清屏
	m_MemDC.FillSolidRect(&m_Rect, m_bgColor);

	//在内存画布中绘制树
	drawLeaf(x, y, m_Rect.Height()/5, 270, 50, m_C);

	if (m_dir) {
		m_C += 0.5;
		if (m_C > 18)
			m_dir = FALSE;
	} else {
		m_C -= 0.5;
		if (m_C < -18)
			m_dir = TRUE;
	}

	//把树拷贝到物理画布中
	m_DC.BitBlt(0, 0, m_Rect.Width(), m_Rect.Height(),
		&m_MemDC, 0, 0, SRCCOPY);

	CDialog::OnTimer(nIDEvent);
}

void CTreeDlg::drawLeaf(double x, double y, double L, double A, float B, float C)
{
	double s1, s2, s3;
	s1 = 2;
	s2 = 3;
	s3 = 1.3;
	int x1,y1,x1L,y1L,x1R,y1R,x2,y2,x2R,y2R,x2L,y2L;
	if(L > s1)
	{
		x2 = (int)(x + L * cos(A * PI));
		y2 = (int)(y + L * sin(A * PI));
		x2R = (int)(x2 + L / s2 * cos((A + B) * PI));
		y2R = (int)(y2 + L / s2 * sin((A + B) * PI));
		x2L = (int)(x2 + L / s2 * cos((A - B) * PI));
		y2L = (int)(y2 + L / s2 * sin((A - B) * PI));
		
		x1 = (int)(x + L / s2 * cos(A * PI));
		y1 = (int)(y + L / s2 * sin(A * PI));
		x1L = (int)(x1 + L / s2 * cos((A - B) * PI));
		y1L = (int)(y1 + L / s2 * sin((A - B) * PI));
		x1R = (int)(x1 + L / s2 * cos((A + B) * PI));
		y1R = (int)(y1 + L / s2 * sin((A + B) * PI));
		
		
		m_MemDC.MoveTo((int)x,(int)y);
		m_MemDC.LineTo(x2,y2);
		m_MemDC.LineTo(x2R,y2R);
		m_MemDC.MoveTo(x2,y2);
		m_MemDC.LineTo(x2L,y2L);
		m_MemDC.MoveTo(x1,y1);
		m_MemDC.LineTo(x1L,y1L);
		m_MemDC.MoveTo(x1,y1);
		m_MemDC.LineTo(x1R,y1R);
		
		drawLeaf(x2, y2, L / s3, A + C, B, C);
		drawLeaf(x2R, y2R, L / s2, A + B, B, C);
		drawLeaf(x2L, y2L, L / s2, A - B, B, C);
		drawLeaf(x1L, y1L, L / s2, A - B, B, C);
		drawLeaf(x1R, y1R, L / s2, A + B, B, C);
	}  
}