Win32 > Programs

Mouse Press Program

#include<windows.h>
#define MAXPOINTS 1000;

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

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

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

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

   hwnd = CreateWindow(szAppName,TEXT ("Draw a Clover"),
                          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 POINT pt[1000];
     static int   iCount ;
     HDC          hdc ;
     int          i, j ;
     PAINTSTRUCT ps ;

     switch (message)
     {
     case WM_LBUTTONDOWN:
          iCount = 0 ;
          InvalidateRect (hwnd, NULL, TRUE) ;
          return 0 ;

     case WM_MOUSEMOVE:
          if (wParam & MK_LBUTTON && iCount < 1000)
          {
               pt[iCount ].x = LOWORD (lParam) ;
               pt[iCount++].y = HIWORD (lParam) ;
               hdc = GetDC (hwnd) ;
               SetPixel (hdc, LOWORD (lParam), HIWORD (lParam), 0) ;
               ReleaseDC (hwnd, hdc) ;
          }
          return 0 ;

     case WM_LBUTTONUP:
          InvalidateRect (hwnd, NULL, FALSE) ;
          return 0 ;

     case WM_PAINT:
          hdc = BeginPaint (hwnd, &ps) ;
          SetCursor (LoadCursor (NULL, IDC_WAIT)) ;
          ShowCursor (TRUE) ;
          for (i = 0 ; i < iCount - 1 ; i++)
               for (j = i + 1 ; j < iCount ; j++)
               {
                    MoveToEx (hdc, pt[i].x, pt[i].y, NULL) ;
                    LineTo   (hdc, pt[j].x, pt[j].y) ;
               }
          ShowCursor (FALSE) ;
          SetCursor (LoadCursor (NULL, IDC_ARROW)) ;
          EndPaint (hwnd, &ps) ;
          return 0 ;

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