//This is a drawing program

public U0 SpeedLineDemo()
{
  I64 msg_code,cnt,x1,y1,x2,y2,arg1,arg2,color=BLACK;
  CDC *dc=DCAlias;
  dc->color=color;
  SettingsPush; //See SettingsPush
  Fs->win_inhibit=WIG_TASK_DFT-WIF_SELF_FOCUS-WIF_SELF_BORDER;
  AutoComplete;
  WinBorder;
  WinMax;
  DocClear;
  DCFill;
  do
  {
    msg_code=GetMsg(&arg1,&arg2,
                    1<<MSG_KEY_DOWN+1<<MSG_MS_L_DOWN+1<<MSG_MS_R_UP);
    switch (msg_code)
    {
    case MSG_MS_R_UP:
      color=PopUpColor;
      if (color>=0)
        dc->color=color;
      break;
    case MSG_MS_L_DOWN:
      x1=arg1;
      y1=arg2;
      x2=arg1;
      y2=arg2;
      cnt=0;
      while (msg_code!=MSG_MS_L_UP)
      {
        dc->thick=0.04*ms.speed;
        GrLine3(dc,x1,y1,0,x2,y2,0);
        msg_code=GetMsg(&arg1,&arg2,
                        1<<MSG_MS_L_UP+1<<MSG_MS_MOVE);
        x1=x2;
        y1=y2;
        x2=arg1;
        y2=arg2;
      }
      GrLine3(dc,x1,y1,0,x2,y2,0);
      break;
    case MSG_KEY_DOWN:
      break;
    }
  }
  while (msg_code!=MSG_KEY_DOWN || !arg1);
  GetMsg(,,1<<MSG_KEY_UP);
  DCFill;
  DCDel(dc);
  SettingsPop;
}

SpeedLineDemo;  //Execute when #included