VC画图用到的主要方法

最新推荐文章于 2024-05-17 11:25:46 发布

xpp02

最新推荐文章于 2024-05-17 11:25:46 发布

阅读量199

点赞数

1。鼠标落下，记录鼠标的起始位置

void CMyEasyDrawView::OnLButtonDown(UINT nFlags, CPoint point) { // TODO: 在此添加消息处理程序代码和/或调用默认值 //graph->m_nType=dlg-> m_bStartDraw = true; m_PtPress = m_PtLast = point;

CView::OnLButtonDown(nFlags, point); }

2.鼠标抬起，画图结束，记录下画图的所有参数 oid CMyEasyDrawView::OnLButtonUp(UINT nFlags, CPoint point) { DrawDialog *dlg=CMainFrame::GetDrawTool(); if (m_bStartDraw) { // 创建新图形对象 EasyGraphics* graph = new EasyGraphics; // 对图形属性赋值 graph->m_nType = m_nGraphType; graph->m_clrColor =dlg->m_clrColor; graph->m_nLineType = dlg->m_nType; graph->m_nLineWidth = dlg->m_lineWide; graph->m_PtTopLeft = m_PtPress; graph->m_PtBottomRight = point; // 添加到图形容器中 m_GraphAry.Add(graph); // 一个绘制结束 m_bStartDraw = false; // 让视图重绘 Invalidate(); } CView::OnLButtonUp(nFlags, point); } 3.鼠标移动产生的动感 void CMyEasyDrawView::OnMouseMove(UINT nFlags, CPoint point) { if (m_bStartDraw) { CDC* pDC = GetDC(); int nDrawMode = pDC->SetROP2(R2_NOTXORPEN);// 设置为“异或模式” DrawDialog* dlg = CMainFrame::GetDrawTool(); EasyGraphics* graph = new EasyGraphics;// 临时绘制对象 // 对图形属性赋值; graph->m_nType = m_nGraphType; graph->m_clrColor =dlg->m_clrColor; graph->m_nLineType = dlg->m_nType; graph->m_nLineWidth = dlg->m_lineWide; graph->m_PtTopLeft = m_PtPress; graph->m_PtBottomRight = m_PtLast; DrawGraphics(pDC, graph);// 擦除上次绘制图形 graph->m_PtBottomRight = point; DrawGraphics(pDC, graph);// 绘制新图形 m_PtLast = point;// 保存当前鼠标坐标 pDC->SetROP2(nDrawMode); if(graph!=NULL) { delete graph; graph=NULL; } ReleaseDC(pDC); } CView::OnMouseMove(nFlags, point); } 4.画图操作函数 void CMyEasyDrawView::DrawGraphics(CDC* pDC, EasyGraphics* graph) { LOGBRUSH logBrush; logBrush.lbStyle = BS_SOLID; logBrush.lbColor = graph->m_clrColor; CPen pen(graph->m_nLineType |PS_GEOMETRIC|PS_ENDCAP_ROUND, graph->m_nLineWidth, &logBrush); // 选中新的笔对象 CPen*oldPen = pDC->SelectObject(&pen); // 使用透明画刷 CBrush* oldBrush = (CBrush*)pDC->SelectStockObject(NULL_BRUSH); switch (graph->m_nType) { case EG_RECT: // 绘制矩形 pDC->Rectangle(graph->m_PtTopLeft.x, graph->m_PtTopLeft.y, graph->m_PtBottomRight.x, graph->m_PtBottomRight.y); break; case EG_CIRCLE: // 绘制椭圆 pDC->Ellipse(graph->m_PtTopLeft.x, graph->m_PtTopLeft.y, graph->m_PtBottomRight.x, graph->m_PtBottomRight.y); break; default: // 绘制直线 pDC->MoveTo(graph->m_PtTopLeft); pDC->LineTo(graph->m_PtBottomRight); } pDC->SelectObject(oldPen); pDC->SelectObject(oldBrush); } 5.初始设置 void CMyEasyDrawView::OnDraw(CDC* pDC/*pDC*/) { CMyEasyDrawDoc* pDoc = GetDocument(); ASSERT_VALID(pDoc); if (!pDoc) return; // TODO: 在此处为本机数据添加绘制代码 CRect rect; GetClientRect(rect); CDC memDC; CBitmap MemBitmap; //设备描述表初始话 memDC.CreateCompatibleDC(NULL); //建立与屏幕显示兼容的内存显示设备 MemBitmap.CreateCompatibleBitmap(pDC,rect.Width(),rect.Height()); //选取空白位图 memDC.SelectObject(MemBitmap); memDC.FillSolidRect(100,0,rect.Width(),rect.Height(),RGB(255,0,0)); EasyGraphics* graph=NULL; for(INT_PTR i=0;i<m_GraphAry.GetCount();i++) { graph=(EasyGraphics*)m_GraphAry[i]; DrawGraphics(&memDC,graph); } pDC->BitBlt(0,0,rect.Width(),rect.Height(),&memDC,0,0,SRCCOPY); }