drawdemoview.cpp

Windows CE 5.0下GDI绘图示例程序.

// DrawDemoView.cpp : implementation of the CDrawDemoView class
//

#include "stdafx.h"
#include "DrawDemo.h"

#include "DrawDemoDoc.h"
#include "DrawDemoView.h"

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

/////////////////////////////////////////////////////////////////////////////
// CDrawDemoView

IMPLEMENT_DYNCREATE(CDrawDemoView, CView)

BEGIN_MESSAGE_MAP(CDrawDemoView, CView)
	//{{AFX_MSG_MAP(CDrawDemoView)
		// NOTE - the ClassWizard will add and remove mapping macros here.
		//    DO NOT EDIT what you see in these blocks of generated code!
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CDrawDemoView construction/destruction

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

}

CDrawDemoView::~CDrawDemoView()
{
}

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

	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CDrawDemoView drawing

void CDrawDemoView::OnDraw(CDC* pDC)
{
	CDrawDemoDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);

	// TODO: add draw code for native data here
	//DisRGB();
	CLineDemo();
	CRect rect;
	GetClientRect(&rect);
	DrawTree(rect.Width ()/2,rect.bottom , 80, 1.67 ,10);
}

/////////////////////////////////////////////////////////////////////////////
// CDrawDemoView diagnostics

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

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

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

/////////////////////////////////////////////////////////////////////////////
// CDrawDemoView message handlers

void CDrawDemoView::DisRGB()
{
	CDC *pDC = new CClientDC(this);
	CBrush RedBrush;
	RedBrush.CreateSolidBrush (RGB(255,0,0));
	CBrush *pOldBrush = pDC ->SelectObject (&RedBrush);
	CRect rect;
	GetClientRect(&rect);
	pDC->Rectangle (rect.left ,rect.top ,rect.right ,rect.Height ()/3 );

	Sleep(300);
	CBrush GreenBrush;
	GreenBrush.CreateSolidBrush (RGB(0,255,0));
	pOldBrush = pDC ->SelectObject (&GreenBrush);
	pDC->Rectangle (rect.left ,rect.Height()/3+1,rect.right ,rect.Height ()*2/3 );

	Sleep(300);
	CBrush BlueBrush;
	BlueBrush.CreateSolidBrush (RGB(0,0,255));
	pOldBrush = pDC ->SelectObject (&BlueBrush);
	pDC->Rectangle (rect.left ,rect.Height()*2/3+1,rect.right ,rect.bottom );

	pDC->SelectObject (pOldBrush);
	delete pDC;
}
/****************************************************************************
* 名称：random()
* 功能：取随机数。
* 入口参数：seed   随机数范围(0 -- seed-1)
* 出口参数：返回值即是取得的随机数
****************************************************************************/
DWORD  random(DWORD seed)
{  DWORD temp;

temp = rand();
temp = temp % seed;
return(temp);
}

/****************************************************************************
* 名称：CLineDemo()
* 功能：彩色线演示程序。以中心点为准，不断的画各种随机角度、随机长度、随机颜色画直线。
* 入口参数：无
* 出口参数：无
****************************************************************************/
void CDrawDemoView::CLineDemo()
{
	POINT  p0,p1; 
	DWORD  no;
	CPaintDC dc(this);

	CRect rect;

	CPen *pOldPen;
	CPen *pNewPen = new CPen();

	CBrush *pOldBrush;
	CBrush *pNewBrush = new CBrush();
	GetClientRect(&rect);
	const CENTER_X=rect.Width ()/2;
	const CENTER_Y=rect.Height ()/2;

	for(no=0; no<400; no++)
	{  /* 取第一个点坐标 */
		p0.x = random(rect.Width ());
		p0.y = random(rect.Height ());
		//color = random(15)+1;     // 不使用黑色(背景色)
	
		/* 计算出中心对称点 */
		p1.x = 2*CENTER_X - p0.x;
		p1.y = 2*CENTER_Y - p0.y;
		pNewPen->CreatePen (PS_SOLID,1,RGB((BYTE)random(255),(BYTE)random(255),(BYTE)random(255)));
		pOldPen=dc.SelectObject (pNewPen);
		dc.MoveTo (p0);
		dc.LineTo (p1);
		Sleep(50);
	}
	dc.FillSolidRect(rect,RGB(255,255,255));

	//彩色矩形演示程序。取得随机起点及长、宽，然后画填充矩形
	for(no=0; no<100; no++)
	{  /* 取第一个点坐标 */
		p0.x = random(rect.Width ());
		p0.y = random(rect.Height ());
		//color = random(15)+1;     // 不使用黑色(背景色)
	
		/* 取第二点坐标 */
		p1.x = random(rect.Width ());
		p1.y = random(rect.Height ());
		pNewBrush->CreateSolidBrush(RGB((BYTE)random(255),(BYTE)random(255),(BYTE)random(255)));
		pOldBrush=dc.SelectObject (pNewBrush);
		dc.Rectangle(p0.x,p0.y,p1.x,p1.y);
		Sleep(50);
	}
	dc.FillSolidRect(rect,RGB(255,255,255));

	//彩色画填充圆演示程序。
	for(no=0; no<200; no++)
	{  /* 取第一个点坐标 */
		p0.x = random(rect.Width ());
		p0.y = random(rect.Height ());
		//color = random(15)+1;     // 不使用黑色(背景色)
		
		/* 取第二点坐标 */
		p1.x = random(rect.Width ());
		p1.y = random(rect.Height ());
		dc.SelectStockObject (NULL_BRUSH);
		//pNewBrush->CreateSolidBrush(RGB((BYTE)random(255),(BYTE)random(255),(BYTE)random(255)));
		pNewPen->CreatePen (PS_SOLID,1,RGB((BYTE)random(255),(BYTE)random(255),(BYTE)random(255)));
		//pOldBrush=dc.SelectObject (pNewBrush);
		pOldPen=dc.SelectObject (pNewPen);
		//dc.Rectangle(p0.x,p0.y,p1.x,p1.y);
		dc.Ellipse (p0.x,p0.y,p1.x,p1.y);
		Sleep(50);
	}
	dc.FillSolidRect(rect,RGB(255,255,255));
}
/****************************************************************************
* 名称：DrawTree()
* 功能：使用图形分形学来实现一棵树的绘画。
* 入口参数：xStart,yStart   树枝/树干的起始点位置
*           length          树枝/树干的长度
*           angle           树枝/树干的倾斜角度(弧度)
*           num             递归层次数
* 出口参数：无
****************************************************************************/
void CDrawDemoView::DrawTree(int xStart, int yStart, double length, double angle, int num)
{
	CPaintDC dc(this);
	CPen *pOldPen;
	CPen *pNewPen = new CPen();
	int xEnd, yEnd;
	
	if(num == 0) return;  	// 本子树已画完
	
	xEnd = xStart + (int)(length * cos(angle));
	yEnd = yStart - (int)(length * sin(angle));	// 由于y方向相反，所以要相减
	
	// 画本子树的树干
	pNewPen->CreatePen (PS_SOLID,1,RGB((BYTE)random(255),(BYTE)random(255),(BYTE)random(255)));
	pOldPen=dc.SelectObject (pNewPen);
	dc.MoveTo (xStart, yStart);
	dc.LineTo (xEnd, yEnd);
	
	// 画本子树的左叉树枝
	DrawTree( xEnd, yEnd, 
		length * 0.6,
		angle + 0.624,
		num - 1 );
	
	// 画本子树的中叉树枝
	DrawTree( xEnd, yEnd, 
		length * 0.85,
		angle + 0.08,
		num - 1 );
	
	// 画本子树的右叉树枝
	DrawTree( xEnd, yEnd, 
		length * 0.65,
		angle - 0.6,
		num - 1 );
}