win32 连接图片

         win32连接图片原理:

                             将图片1写入到一个 内存位置,将图片2写到另一个内存位置,然后新建一个新的足以容纳这2张图片的内存,分别将2个图片,依次拷贝到较大的新的内存位置.

先来看看代码:

       

/*----------------------------------------
BRICKS1.C -- LoadBitmap Demonstration
(c) Charles Petzold, 1998
----------------------------------------*/

#include <windows.h>

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
					PSTR szCmdLine, int iCmdShow)
{
	static TCHAR szAppName [] = TEXT ("Bricks1") ;
	HWND         hwnd ;
	MSG          msg ;
	WNDCLASS     wndclass ;

	wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
	wndclass.lpfnWndProc   = WndProc ;
	wndclass.cbClsExtra    = 0 ;
	wndclass.cbWndExtra    = 0 ;
	wndclass.hInstance     = hInstance ;
	wndclass.hIcon         = LoadIcon (NULL, IDI_APPLICATION) ;
	wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;
	//	wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
	wndclass.hbrBackground = NULL ;
	wndclass.lpszMenuName  = NULL ;
	wndclass.lpszClassName = szAppName ;

	if (!RegisterClass (&wndclass))
	{
		MessageBox (NULL, TEXT ("This program requires Windows NT!"),
			szAppName, MB_ICONERROR) ;
		return 0 ;
	}

	hwnd = CreateWindow (szAppName, TEXT ("LoadBitmap Demo"), 
		WS_OVERLAPPEDWINDOW, 
		CW_USEDEFAULT, CW_USEDEFAULT,
		CW_USEDEFAULT, CW_USEDEFAULT,
		NULL, NULL, hInstance, NULL) ;

	ShowWindow (hwnd, iCmdShow) ;
	UpdateWindow (hwnd) ;

	while (GetMessage (&msg, NULL, 0, 0))
	{
		TranslateMessage (&msg) ;
		DispatchMessage (&msg) ;
	}
	return msg.wParam ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	static HBITMAP hBitmap,hBitmap2,memBM ;
	static int     cxClient, cyClient, cxSource, cySource,cxSource2, cySource2 ;
	BITMAP         bitmap,bitmap2 ;
	static HDC            hdc, hdcMem = NULL,hdcMem2 ,hdcMem3;
	static HINSTANCE      hInstance ;
	//	 HBITMAP memBM;
	//	 Getwindows
	static int            x = -10, y = 0,x2 = 0,m_x = 0;
	static int            xfirst ;
	static int            xsecond;
	PAINTSTRUCT    ps ;
	POINT          MousePointFirst;
	POINT          MousePointSecond;
	RECT           ClientRect;
	static BOOL    sign = TRUE;
    static BOOL    Isfirst = TRUE;
	switch (message)
	{
	case WM_CREATE:
		hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;

		hBitmap = LoadBitmap (hInstance, TEXT ("IDB_BITMAP5")) ;
		hBitmap2 = LoadBitmap (hInstance,TEXT("IDB_BITMAP3"));
		//      hdcMem = CreateCompatibleDC (hdc) ;
		//hdcMem2 = CreateCompatibleDC (hdc) ;
		//hdcMem3 = CreateCompatibleDC (hdc) ;
		//SelectObject(hdcMem,hBitmap);
		//SelectObject(hdcMem2,hBitmap2);


		//      GetObject (hBitmap, sizeof (BITMAP), &bitmap) ;
		//GetObject (hBitmap2, sizeof (BITMAP), &bitmap2) ;

		//      cxSource = bitmap.bmWidth ;
		//      cySource = bitmap.bmHeight ;

		//cxSource2 = bitmap2.bmWidth ;
		//cySource2 = bitmap2.bmHeight ;

		//memBM   = CreateCompatibleBitmap(hdc,cxSource*2,cySource);
		//SelectObject(hdcMem3,memBM);

		//BitBlt(hdcMem3,0,0,cxSource,cySource,hdcMem,0,0,SRCCOPY);
		//DeleteDC(hdcMem);

		//BitBlt(hdcMem3,cxSource,0,cxSource2,cySource2,hdcMem2,0,0,SRCCOPY);
		//DeleteDC(hdcMem2);



		return 0 ;

	case WM_SIZE:
		cxClient = LOWORD (lParam) ;
		cyClient = HIWORD (lParam) ;
		//	  x2       = 0;
		return 0 ;

	case WM_PAINT:
		hdc = BeginPaint (hwnd, &ps) ;

		if(sign == TRUE)
		{



			hdcMem = CreateCompatibleDC (hdc) ;
			hdcMem2 = CreateCompatibleDC (hdc) ;
			hdcMem3 = CreateCompatibleDC (hdc) ;
			SelectObject(hdcMem,hBitmap);
			SelectObject(hdcMem2,hBitmap2);


			GetObject (hBitmap, sizeof (BITMAP), &bitmap) ;
			GetObject (hBitmap2, sizeof (BITMAP), &bitmap2) ;

			cxSource = bitmap.bmWidth ;
			cySource = bitmap.bmHeight ;

			cxSource2 = bitmap2.bmWidth ;
			cySource2 = bitmap2.bmHeight ;

			memBM   = CreateCompatibleBitmap(hdc,cxSource+cxSource2,cySource);
			SelectObject(hdcMem3,memBM);

			BitBlt(hdcMem3,0,0,cxSource,cySource,hdcMem,0,0,SRCCOPY);
			DeleteDC(hdcMem);

			BitBlt(hdcMem3,cxSource,0,cxSource2,cySource2,hdcMem2,0,0,SRCCOPY);
			DeleteDC(hdcMem2);


			BitBlt(hdc,0,0,cxSource+cxSource2,cySource,hdcMem3,cxSource,0,SRCCOPY);
		}
		else
		{
			m_x += 100;
			hdcMem = CreateCompatibleDC (hdc) ;
			hdcMem2 = CreateCompatibleDC (hdc) ;
			hdcMem3 = CreateCompatibleDC (hdc) ;
			SelectObject(hdcMem,hBitmap);
			SelectObject(hdcMem2,hBitmap2);


			GetObject (hBitmap, sizeof (BITMAP), &bitmap) ;
			GetObject (hBitmap2, sizeof (BITMAP), &bitmap2) ;

			cxSource = bitmap.bmWidth ;
			cySource = bitmap.bmHeight ;

			cxSource2 = bitmap2.bmWidth ;
			cySource2 = bitmap2.bmHeight ;

			memBM   = CreateCompatibleBitmap(hdc,cxSource+cxSource2,cySource);
			SelectObject(hdcMem3,memBM);

			BitBlt(hdcMem3,0,0,cxSource,cySource,hdcMem,0,0,SRCCOPY);
			DeleteDC(hdcMem);

			BitBlt(hdcMem3,cxSource,0,cxSource2,cySource2,hdcMem2,0,0,SRCCOPY);
			DeleteDC(hdcMem2);
			if(x >= cxSource )
			{			
				BitBlt(hdc,0,0,cxSource+cxSource2,cySource,hdcMem3,cxSource,0,SRCCOPY);
			}
			else
			{
				BitBlt(hdc,0,0,cxSource+cxSource2,cySource,hdcMem3,m_x,0,SRCCOPY);

			}
		}
		

		DeleteDC (hdcMem3) ;
		EndPaint (hwnd, &ps) ;
		return 0 ;


	case WM_MOUSEMOVE:
		if(wParam & MK_LBUTTON)
		{
			sign = FALSE;

			//GetObject (hBitmap, sizeof (BITMAP), &bitmap) ;

			//cxSource = bitmap.bmWidth ;
			//cySource = bitmap.bmHeight ;

			if(Isfirst == TRUE)
			{

				x = 0;
				Isfirst = FALSE;
			}
			else
			{
				
				xfirst = xsecond;  		   
				GetCursorPos(&MousePointSecond);
				xsecond = MousePointSecond.x;
				x=xsecond - xfirst;	


			}
		
            
			InvalidateRect(hwnd,NULL,TRUE);
		}
		return 0;

	case WM_LBUTTONUP:

		sign = FALSE;
		//if(x2 > 500)
		//{
		// x = x2 = 0;
		// SelectObject (hdcMem, hBitmap2) ;
		//  // BitBlt (hdc, 0, 0, cxSource, cySource, hdcMem, 0, 0, SRCCOPY) ;
		//}
		//else
		//{

		//          x = x2 = 0;  
		//  	    SelectObject (hdcMem, hBitmap); 
		//}

		InvalidateRect(hwnd,NULL,TRUE);
		return 0;

	case WM_DESTROY:
		DeleteObject (hBitmap) ;
		PostQuitMessage (0) ;
		return 0 ;
	}
	return DefWindowProc (hwnd, message, wParam, lParam) ;
}

   图片连接的实现,主要是 WM_PAINT里的代码,我们具体来分析一下:

   (1)创建一个与指定设备兼容的内存设备上下文环境（DC）     

hdcMem = CreateCompatibleDC (hdc) ;

hdcMem2 = CreateCompatibleDC (hdc) ;

   hdcMem3 = CreateCompatibleDC (hdc) ;

  (2)将hdcMem,hdcMem2,分别关联要进行连接的图片   

   SelectObject(hdcMem,hBitmap);
   SelectObject(hdcMem2,hBitmap2);

(3)创建一个内存兼容图片,图片的大小应该是2张图片的2倍(看水平,还是垂直),并将兼容图片和hdcMem3关联

    memBM   = CreateCompatibleBitmap(hdc,cxSource+cxSource2,cySource);
    SelectObject(hdcMem3,memBM);

(4)将hdcMem1 hdcMem2,依次拷贝到hdcMem3中,注意,第二次的起始位置,应该是第一次图片的长度

    BitBlt(hdcMem3,0,0,cxSource,cySource,hdcMem,0,0,SRCCOPY);
    DeleteDC(hdcMem);
    BitBlt(hdcMem3,cxSource,0,cxSource2,cySource2,hdcMem2,0,0,SRCCOPY);
    DeleteDC(hdcMem2);

(5)最后将hdcMem3写到窗口的dc,便可以显示出来了哦

BitBlt(hdc,0,0,cxSource+cxSource2,cySource,hdcMem3,0,0,SRCCOPY);