labwindows制作特殊图形面板

可以利用labwindows制作特殊图形的面板，比如圆形，椭圆，正方形等等。

制作步骤如下：

1. 获取panel所在窗口句柄
   DWND hwnd;
   GetPanelAttribute（panel，control，ATTR_SYSTEM_HANDLE,(int*)&hwnd）;
2. 获取标题栏高度
   int titleLen=GetsyetemMetrics（SM_CYCAPTION）;
3. 获得窗口大小
   RECT FullRect;
   GetWindowRect(hwnd,FullRect);
4. 获取客户区大小
   RECT ClientRect;
   GetClientRect(hwnd,ClientRect);
5. 制作特殊形状图形
   A：椭圆：CreateEllipticRgn(left,top,right,bottom);
   B:带圆角的长方形：CreateRoundRectRgn(left,top,right,bottom,angle,angle);
   C:多边形区域：CreatePloygonRgn
   D:可重叠多边形区域：CreatePloyPloygonRgn
   D:合并两个区域CombineRgn（Dis，Sor1，Sor2，Mode）；其中MODE有愈多选项，根据 不同选项得到结果不同
   E：删除合并后其他区域的GDI： DeleteObject
6. 制作特殊区域 SetWindowRgn(hwnd,RECT rect，TURE）；

GetPanelAttribute(panel,ATTR_SYSTEM_WINDOW_HANDLE,(int*)&hwnd);
		   GetPanelAttribute(panel,ATTR_TITLEBAR_VISIBLE,&titlebar);
		   if(titlebar)
		   {
			   TitlebarHeight=GetSystemMetrics(SM_CYCAPTION);
		   }
		   GetWindowRect(hwnd,&WindowRect);
		   GetClientRect(hwnd,&ClientRect);															
		   fullheight=WindowRect.bottom-WindowRect.top;
		   fullwidth=WindowRect.right-WindowRect.left;
		   verticalborderwidth =(fullheight-TitlebarHeight-ClientRect.bottom)/2;
		   horizentalborderwidth=(fullwidth-ClientRect.right)/2;
		   ShapeRect.left=horizentalborderwidth;
		   ShapeRect.top=TitlebarHeight+verticalborderwidth;
		   ShapeRect.right=horizentalborderwidth+ClientRect.right;
		   ShapeRect.bottom=horizentalborderwidth+ClientRect.bottom+TitlebarHeight;
			 int arcvalue;
//以下绘制区域重复，实际代码中任选其一
//绘制椭圆区域		 					 winrgn=CreateEllipticRgn(ShapeRect.left,ShapeRect.top,ShapeRect.right,ShapeRect.bottom);  
				 SetWindowRgn(hwnd,winrgn,1);
				
				   
//绘制圆角矩形区域
				   GetCtrlVal(panel,PANEL_NUMERICGAUGE,&arcvalue);
				   winrgn=CreateRoundRectRgn(ShapeRect.left,ShapeRect.top,ShapeRect.right,
										ShapeRect.bottom,arcvalue,arcvalue);
				   SetWindowRgn(hwnd,winrgn,TRUE);
				 
				   
//绘制两个圆合并区域
				   GetCtrlVal(panel,PANEL_NUMERICGAUGE,&arcvalue); 
				   winrgn=CreateEllipticRgn(ShapeRect.left,ShapeRect.top,ShapeRect.bottom,ShapeRect.right);
				   innerrgn=CreateEllipticRgn(ShapeRect.left+arcvalue,ShapeRect.top+arcvalue,
											  ShapeRect.bottom-arcvalue,ShapeRect.right-arcvalue);
				   CombineRgn(winrgn,winrgn,innerrgn,RGN_DIFF);
				   DeleteObject(innerrgn);
				   SetWindowRgn(hwnd,winrgn,TRUE);