[API] 타이머

LRESULT CALLBACK WndProc(HWND hWnd,UINT iMessage,WPARAM wParam,LPARAM lParam)
{
 HDC hdc;
 PAINTSTRUCT ps;
 int i;
 switch (iMessage)
 {
 case WM_CREATE:
  SetTimer(hWnd,1,50,NULL);
  return 0;
 case WM_TIMER:
  hdc = GetDC(hWnd);
  for(i = 0 ;i <1000; i++)
  {
   SetPixel(hdc,rand()%500,rand()%400,RGB(rand()%256,rand()%256,rand()%256));
  }
  return 0;
 case WM_LBUTTONDOWN:
  hdc = GetDC(hWnd);
  Ellipse(hdc,LOWORD(lParam)-10,HIWORD(lParam)-10,LOWORD(lParam)+10,HIWORD(lParam)+10);
  ReleaseDC(hWnd,hdc);
  return 0;
 case WM_PAINT:
  hdc=BeginPaint(hWnd,&ps);
  EndPaint(hWnd,&ps);
  return 0;
 case WM_DESTROY:
  PostQuitMessage(0);
  return 0;
 }
 return(DefWindowProc(hWnd,iMessage,wParam,lParam));
}