____                _       __
    / __ )____  _____   | |     / /___ ___________
   / __  / __ \/ ___/   | | /| / / __ `/ ___/ ___/
  / /_/ / /_/ (__  )    | |/ |/ / /_/ / /  (__  )
 /_____/\____/____/     |__/|__/\__,_/_/  /____/

       A futuristic real-time strategy game.
          This file is part of Bos Wars.

(C) Copyright 2001-2007 by the Bos Wars and Stratagus Project. Distributed under the "GNU General Public License"

---

action_follow.cpp

Go to the documentation of this file.

//     ____                _       __               
//    / __ )____  _____   | |     / /___ ___________
//   / __  / __ \/ ___/   | | /| / / __ `/ ___/ ___/
//  / /_/ / /_/ (__  )    | |/ |/ / /_/ / /  (__  ) 
// /_____/\____/____/     |__/|__/\__,_/_/  /____/  
//                                              
//       A futuristic real-time strategy game.
//          This file is part of Bos Wars.
//
//
//      (c) Copyright 2001-2007 by Lutz Sammer and Jimmy Salmon
//
//      This program is free software; you can redistribute it and/or modify
//      it under the terms of the GNU General Public License as published by
//      the Free Software Foundation; only version 2 of the License.
//
//      This program is distributed in the hope that it will be useful,
//      but WITHOUT ANY WARRANTY; without even the implied warranty of
//      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//      GNU General Public License for more details.
//
//      You should have received a copy of the GNU General Public License
//      along with this program; if not, write to the Free Software
//      Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
//      02111-1307, USA.
//


/*----------------------------------------------------------------------------
--  Includes
----------------------------------------------------------------------------*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "stratagus.h"
#include "unit.h"
#include "unittype.h"
#include "pathfinder.h"
#include "map.h"
#include "interface.h"
#include "actions.h"

/*----------------------------------------------------------------------------
--  Variables
----------------------------------------------------------------------------*/

/*----------------------------------------------------------------------------
--  Function
----------------------------------------------------------------------------*/

void HandleActionFollow(CUnit *unit)
{
    CUnit *goal;

    if (unit->Wait) {
        unit->Wait--;
        return;
    }

    //
    // Reached target
    //
    if (unit->SubAction == 128) {
        goal = unit->Orders[0]->Goal;
        if (!goal || !goal->IsVisibleAsGoal(unit->Player)) {
            DebugPrint("Goal gone\n");
            if (goal) {
                goal->RefsDecrease();
            }
            unit->Orders[0]->Goal = NoUnitP;
            unit->ClearAction();
            return;
        }

        if (goal->X == unit->Orders[0]->X && goal->Y == unit->Orders[0]->Y) {
            // Move to the next order
            if (unit->OrderCount > 1) {
                goal->RefsDecrease();
                unit->Orders[0]->Goal = NoUnitP;
                unit->ClearAction();
                return;
            }

            // Reset frame to still frame while we wait
            // FIXME: Unit doesn't animate.
            unit->Frame = unit->Type->StillFrame;
            UnitUpdateHeading(unit);
            unit->Wait = 10;
            if (unit->Orders[0]->Range > 1) {
                unit->Orders[0]->Range = 1;
                unit->SubAction = 0;
            }
            return;
        }

        unit->SubAction = 0;
    }

    if (!unit->SubAction) { // first entry
        unit->SubAction = 1;
        NewResetPath(unit);
        Assert(unit->State == 0);
    }

    switch (DoActionMove(unit)) { // reached end-point?
        case PF_UNREACHABLE:
            //
            // Some tries to reach the goal
            //
            if (unit->Orders[0]->Range <= Map.Info.MapWidth ||
                    unit->Orders[0]->Range <= Map.Info.MapHeight) {
                unit->Orders[0]->Range++;
                break;
            }
            // FALL THROUGH
        case PF_REACHED:
            if (!(goal = unit->Orders[0]->Goal)) { // goal has died
                unit->ClearAction();
                return;
            }
            unit->Orders[0]->X = goal->X;
            unit->Orders[0]->Y = goal->Y;
            unit->SubAction = 128;

            // FALL THROUGH
        default:
            break;
    }

    //
    // Target destroyed?
    //
    if ((goal = unit->Orders[0]->Goal) && !goal->IsVisibleAsGoal(unit->Player)) {
        DebugPrint("Goal gone\n");
        unit->Orders[0]->X = goal->X + goal->Type->TileWidth / 2;
        unit->Orders[0]->Y = goal->Y + goal->Type->TileHeight / 2;
        unit->Orders[0]->Goal = NoUnitP;
        goal->RefsDecrease();
        goal = NoUnitP;
        NewResetPath(unit);
    }

    if (!unit->Anim.Unbreakable) {
        //
        // If our leader is dead or stops or attacks:
        // Attack any enemy in reaction range.
        // If don't set the goal, the unit can than choose a
        //  better goal if moving nearer to enemy.
        //
        if (unit->Type->CanAttack &&
                (!goal || goal->Orders[0]->Action == UnitActionAttack ||
                    goal->Orders[0]->Action == UnitActionStill)) {
            goal = AttackUnitsInReactRange(unit);
            if (goal) {
                CommandAttack(unit, goal->X, goal->Y, NULL, FlushCommands);
                // Save current command to come back.
                unit->SavedOrder = *unit->Orders[0];
                // This stops the follow command and the attack is executed
                unit->ClearAction();
                unit->Orders[0]->Goal = NoUnitP;
            }
        }
    }
}

---