[ft] two puzzled function

[luoyi]

ftcommon.c:

*************************************************************************
  void
  FTDemo_Set_Preload( FTDemo_Handle*  handle,
                      int             preload )
  {
    handle->preload = !!preload;
  }

 Q1: why two '!' here ?

  void
  FTDemo_Set_Current_Pointsize( FTDemo_Handle*  handle,
                                int             point_size,
                                int             res )
  {
    FTDemo_Set_Current_Size( handle, ( point_size * res + 36 ) / 72 );
  }

 Q2: what's the mean of: "( pt * res + 36 ) /72" ?
*************************************************************************