实时动态曲线绘制

1、核心函数如下：DrawWave(CDC *pDC) 这个函数主要是绘制曲线图。OnTimer(UINT nIDEvent) 这个函数式控制实时绘制的计数器函数。 例子代码如下：(给你加了点注释希望你能看懂)void CDrawTest:DrawWave(CDC *pDC)CRect rect;CString str;int i;int m_left,m_top,m_right,m_bottom;int m_Interval = (m_High - m_Low)/10;if (m_Interval < 1) m_Interval = 1; / 获取绘制坐标的文本框 CWnd* pWnd =

2、 GetDlgItem(IDC_COORD);pWnd->GetClientRect(&rect); pDC->Rectangle(&rect); m_left = rect.left+10; m_top = rect.top+10; m_right = rect.right-10; m_bottom = rect.bottom-20; int m_IntervalPan = (m_right - m_left)/11; if (m_IntervalPan < 1 ) m_IntervalPan =1;/ 创建画笔对象CPen* pPenRed = new C

3、Pen;/ 红色画笔 pPenRed->CreatePen(PS_SOLID,1,RGB(255,0,0);/ 创建画笔对象CPen* pPenBlue = new CPen;/ 蓝色画笔 pPenBlue->CreatePen(PS_SOLID,1,RGB(0,0, 255);/ 创建画笔对象CPen* pPenGreen = new CPen;/ 绿色画笔 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(pPe

4、nRed);/ 绘制坐标轴 pDC->MoveTo(m_left,m_top);/ 垂直轴 pDC->LineTo(m_left,m_bottom);/ 水平轴 pDC->LineTo(m_right,m_bottom);/ 写 X 轴刻度值 for(i=0;i<10;i+)/str.Format(_T("%d"),m_Min+i*m_Interval); str.Format(_T("%d"),m_Low+i*m_Interval);pDC->TextOut(m_left+i*m_IntervalPan,m_bottom+

5、3,str); /str.Format(_T("%d"),m_Max); str.Format(_T("%d"),m_High);pDC->TextOut(m_left+10*m_IntervalPan,m_bottom+3,str); / 绘制 X 轴刻度for (i = m_left; i < m_right-20; i += 5)if (i & 1) = 0)/ 10 的倍数 pDC->MoveTo(i + 10, m_bottom);pDC->LineTo(i + 10, m_bottom+4);else/ 10

6、的倍数 pDC->MoveTo(i + 10, m_bottom);pDC->LineTo(i + 10, m_bottom+2);/ 绘制 Y 轴箭头 pDC->MoveTo(m_right-5,m_bottom-5); pDC->LineTo(m_right,m_bottom); pDC->LineTo(m_right-5,m_bottom+5);/ 绘制 X 轴箭头 pDC->MoveTo(m_left-5,m_top+5); pDC->LineTo(m_left,m_top); pDC->LineTo(m_left+5,m_top+5);

7、/ 绘制 Y 轴网格 选择绿色画笔 pDC->SelectObject(pPenGreen);/int iTemp = (m_bottom - m_top)/5;for (i = 1 ;i <= 5 ;i+)pDC->MoveTo(m_left,m_bottom - i*iTemp); pDC->LineTo(m_right,m_bottom - i*iTemp);/数组赋值 if(m_now<1024)m_now+;elsem_now = 0;for(i = m_Low;i<m_High;i+) /m_lCounti=(rand()%10+rand()%1

8、00+rand()%1000)%1024; m_lCounti = (int)(sin(i-m_now)*204);int xTemp;int yTemp;/ 更改成蓝色画笔pDC->SelectObject(pPenBlue);for (i = m_Low; i <= m_High; i=i+3)xTemp = m_left+(i-m_Low)*m_IntervalPan/m_Interval;yTemp = m_bottom/2 - (int) (m_lCounti * m_bottom / 1024); if (yTemp < m_top) yTemp = m_top;

9、if(xTemp >=m_left)&&(xTemp <=m_right)pDC->MoveTo(xTemp, m_bottom/2); pDC->LineTo(xTemp, yTemp);/ 恢复以前的画笔pDC->SelectObject(pOldPen);delete pPenRed;delete pPenBlue;delete pPenGreen;return;void CDrawTest:OnTimer(UINT nIDEvent)/ TODO: Add your message handler code here and/or call

10、 default CRect rect;/ 获取绘制坐标的文本框CWnd* pWnd = GetDlgItem(IDC_COORD); pWnd->GetClientRect(&rect);/ 指针pDC = pWnd->GetDC();pWnd->Invalidate();pWnd->UpdateWindow();/pDC->Rectangle(&rect);/内存绘图CBitmap memBitmap;CBitmap* pOldBmp = NULL; memDC.CreateCompatibleDC(pDC); memBitmap.CreateCompatibleBitmap(pDC,rect.right,rect.bottom);pOldBmp = memDC.SelectObject(&memBitmap); memDC.BitBlt(rect.left,rect.top,rect.right,rect.bottom,pDC,0,0,SRCCOPY); DrawWave(&memDC);pDC->Bit