summaryrefslogtreecommitdiffhomepage
path: root/Stars45/FighterTacticalAI.cpp
blob: 9463a92ed1e98522a4c74a6729811e8c19a74796 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
/*  Starshatter OpenSource Distribution
    Copyright (c) 1997-2004, Destroyer Studios LLC.
    All Rights Reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    * Neither the name "Destroyer Studios" nor the names of its contributors
      may be used to endorse or promote products derived from this software
      without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.

    SUBSYSTEM:    Stars.exe
    FILE:         FighterTacticalAI.cpp
    AUTHOR:       John DiCamillo


    OVERVIEW
    ========
    Fighter-specific mid-level (tactical) AI class
*/

#include "MemDebug.h"
#include "FighterTacticalAI.h"
#include "ShipAI.h"
#include "Ship.h"
#include "ShipDesign.h"
#include "Shot.h"
#include "Element.h"
#include "Instruction.h"
#include "RadioMessage.h"
#include "Sensor.h"
#include "Contact.h"
#include "WeaponGroup.h"
#include "Drive.h"
#include "Sim.h"
#include "StarSystem.h"

#include "Game.h"

// +----------------------------------------------------------------------+

const int WINCHESTER_FIGHTER = 0;
const int WINCHESTER_ASSAULT = 1;
const int WINCHESTER_STRIKE  = 2;
const int WINCHESTER_STATIC  = 3;

// +----------------------------------------------------------------------+

FighterTacticalAI::FighterTacticalAI(ShipAI* ai)
: TacticalAI(ai), secondary_selection_time(0)
{
    for (int i = 0; i < 4; i++)
    winchester[i] = false;

    ai_level = ai->GetAILevel();

    switch (ai_level) {
    default:
    case 2:  THREAT_REACTION_TIME =  1000; break;
    case 1:  THREAT_REACTION_TIME =  3000; break;
    case 0:  THREAT_REACTION_TIME =  6000; break;
    }
}


// +--------------------------------------------------------------------+

FighterTacticalAI::~FighterTacticalAI()
{ }

// +--------------------------------------------------------------------+

bool
FighterTacticalAI::CheckFlightPlan()
{
    navpt = ship->GetNextNavPoint();

    int order = Instruction::PATROL;
    roe       = FLEXIBLE;

    if (navpt) {
        order = navpt->Action();

        switch (order)  {
        case Instruction::LAUNCH:
        case Instruction::DOCK:
        case Instruction::RTB:     roe = NONE;
            break;

        case Instruction::VECTOR:
            roe = SELF_DEFENSIVE;
            if (element_index > 1)
            roe = DEFENSIVE;
            break;

        case Instruction::DEFEND:
        case Instruction::ESCORT:  roe = DEFENSIVE;
            break;

        case Instruction::INTERCEPT:
            if (element_index > 1)
            roe = DEFENSIVE;
            else
            roe = DIRECTED;
            break;

        case Instruction::RECON:
        case Instruction::STRIKE:
        case Instruction::ASSAULT: roe = DIRECTED;
            break;

        case Instruction::PATROL:
        case Instruction::SWEEP:   roe = FLEXIBLE;
            break;

        default: break;
        }

        if (order == Instruction::STRIKE) {
            ship->SetSensorMode(Sensor::GM);

            if (IsStrikeComplete(navpt)) {
                ship->SetNavptStatus(navpt, Instruction::COMPLETE);
            }
        }

        else if (order == Instruction::ASSAULT) {
            if (ship->GetSensorMode() == Sensor::GM)
            ship->SetSensorMode(Sensor::STD);

            if (IsStrikeComplete(navpt)) {
                ship->SetNavptStatus(navpt, Instruction::COMPLETE);
            }
        }

        else {
            if (ship->GetSensorMode() == Sensor::GM)
            ship->SetSensorMode(Sensor::STD);
        }
    }

    switch (roe) {
    case NONE:              ship->SetDirectorInfo(Game::GetText("ai.none"));            break;
    case SELF_DEFENSIVE:    ship->SetDirectorInfo(Game::GetText("ai.self-defensive"));  break;
    case DEFENSIVE:         ship->SetDirectorInfo(Game::GetText("ai.defensive"));       break;
    case DIRECTED:          ship->SetDirectorInfo(Game::GetText("ai.directed"));        break;
    case FLEXIBLE:          ship->SetDirectorInfo(Game::GetText("ai.flexible"));        break;
    default:                ship->SetDirectorInfo(Game::GetText("ai.default"));         break;
    }

    return (navpt != 0);
}

// +--------------------------------------------------------------------+

void
FighterTacticalAI::SelectTarget()
{
    TacticalAI::SelectTarget();

    SimObject* target = ship_ai->GetTarget();

    if (target && (target->Type() == SimObject::SIM_SHIP) &&
            (Game::GameTime() - secondary_selection_time) > THREAT_REACTION_TIME) {
        SelectSecondaryForTarget((Ship*) target);
        secondary_selection_time = Game::GameTime();
    }
}

// +--------------------------------------------------------------------+

void
FighterTacticalAI::SelectTargetDirected(Ship* tgt)
{
    Ship* potential_target = tgt;

    if (!tgt) {
        // try to target one of the element's objectives
        // (if it shows up in the contact list)

        Element* elem = ship->GetElement();

        if (elem) {
            Instruction* objective = elem->GetTargetObjective();

            if (objective) {
                SimObject* obj_sim_obj = objective->GetTarget();
                Ship*      obj_tgt     = 0;

                if (obj_sim_obj && obj_sim_obj->Type() == SimObject::SIM_SHIP)
                obj_tgt = (Ship*) obj_sim_obj;

                if (obj_tgt && ship->FindContact(obj_tgt))
                potential_target = obj_tgt;
            }
        }
    }

    if (!CanTarget(potential_target))
    potential_target = 0;

    ship_ai->SetTarget(potential_target);
    SelectSecondaryForTarget(potential_target);
}

// +--------------------------------------------------------------------+

void
FighterTacticalAI::SelectTargetOpportunity()
{
    // NON-COMBATANTS do not pick targets of opportunity:
    if (ship->GetIFF() == 0)
    return;

    Ship* potential_target    = 0;
    Shot* current_shot_target = 0;

    // pick the closest combatant ship with a different IFF code:
    double target_dist = 1.0e15;
    double min_dist    = 5.0e3;

    // FIGHTERS are primarily anti-air platforms, but may
    // also attack smaller starships:

    Ship* ward = 0;
    if (element_index > 1)
    ward = ship->GetLeader();

    // commit range for patrol/sweep is 80 Km
    // (about 2 minutes for a fighter at max speed)
    if (roe == FLEXIBLE || roe == AGRESSIVE)
    target_dist = ship->Design()->commit_range;

    if (roe < FLEXIBLE)
    target_dist = 0.5 * ship->Design()->commit_range;

    int class_limit = Ship::LCA;

    if (ship->Class() == Ship::ATTACK)
    class_limit = Ship::DESTROYER;

    ListIter<Contact> c_iter = ship->ContactList();
    while (++c_iter) {
        Contact* contact = c_iter.value();
        Ship*    c_ship  = contact->GetShip();
        Shot*    c_shot  = contact->GetShot();
        int      c_iff   = contact->GetIFF(ship);
        bool     rogue   = false;

        if (c_ship)
        rogue = c_ship->IsRogue();

        if (!rogue && (c_iff <= 0 || c_iff == ship->GetIFF() || c_iff == 1000))
        continue;

        // reasonable target?
        if (c_ship && c_ship->Class() <= class_limit && !c_ship->InTransition()) {
            if (!rogue) {
                SimObject* ttgt = c_ship->GetTarget();

                // if we are self-defensive, is this contact engaging us?
                if (roe == SELF_DEFENSIVE && ttgt != ship)
                continue;

                // if we are defending, is this contact engaging us or our ward?
                if (roe == DEFENSIVE && ttgt != ship && ttgt != ward)
                continue;
            }

            // found an enemy, check distance:
            double dist = (ship->Location() - c_ship->Location()).length();

            if (dist < 0.75 * target_dist) {

                // if on patrol, check target distance from navpoint:
                if (roe == FLEXIBLE && navpt) {
                    double ndist = (navpt->Location().OtherHand() - c_ship->Location()).length();
                    if (ndist > 80e3)
                    continue;
                }

                potential_target = c_ship;
                target_dist = dist;
            }
        }

        else if (c_shot && c_shot->IsDrone()) {
            // found an enemy shot, do we have enough time to engage?
            if (c_shot->GetEta() < 10)
            continue;

            // found an enemy shot, check distance:
            double dist = (ship->Location() - c_shot->Location()).length();

            if (!current_shot_target) {
                current_shot_target = c_shot;
                target_dist = dist;
            }

            // is this shot a better target than the one we've found?
            else {
                Ship* ward = ship_ai->GetWard();

                if ((c_shot->IsTracking(ward) && !current_shot_target->IsTracking(ward)) ||
                        (dist < target_dist)) {
                    current_shot_target = c_shot;
                    target_dist = dist;
                }
            }
        }
    }

    if (current_shot_target) {
        ship_ai->SetTarget(current_shot_target);
    }
    else {
        ship_ai->SetTarget(potential_target);
        SelectSecondaryForTarget(potential_target);
    }
}

// +--------------------------------------------------------------------+

int
FighterTacticalAI::ListSecondariesForTarget(Ship* tgt, List<WeaponGroup>& weps)
{
    weps.clear();

    if (tgt) {
        ListIter<WeaponGroup> iter = ship->Weapons();
        while (++iter) {
            WeaponGroup* w = iter.value();

            if (w->Ammo() && w->CanTarget(tgt->Class()))
            weps.append(w);
        }
    }

    return weps.size();
}

void
FighterTacticalAI::SelectSecondaryForTarget(Ship* tgt)
{
    if (tgt) {
        int wix = WINCHESTER_FIGHTER;

        if (tgt->IsGroundUnit())      wix = WINCHESTER_STRIKE;
        else if (tgt->IsStatic())     wix = WINCHESTER_STATIC;
        else if (tgt->IsStarship())   wix = WINCHESTER_ASSAULT;

        WeaponGroup*      best = 0;
        List<WeaponGroup> weps;

        if (ListSecondariesForTarget(tgt, weps)) {
            winchester[wix] = false;

            // select best weapon for the job:
            double range       = (ship->Location() - tgt->Location()).length();
            double best_range  = 0;
            double best_damage = 0;

            ListIter<WeaponGroup> iter  = weps;
            while (++iter) {
                WeaponGroup* w = iter.value();

                if (!best) {
                    best = w;

                    WeaponDesign* d = best->GetDesign();
                    best_range  = d->max_range;
                    best_damage = d->damage * d->ripple_count;

                    if (best_range < range)
                    best = 0;
                }

                else {
                    WeaponDesign* d = w->GetDesign();
                    double w_range  = d->max_range;
                    double w_damage = d->damage * d->ripple_count;

                    if (w_range > range) {
                        if (w_range < best_range || w_damage > best_damage)
                        best = w;
                    }
                }
            }

            // now cycle weapons until you pick the best one:
            WeaponGroup* current_missile = ship->GetSecondaryGroup();

            if (current_missile && best && current_missile != best) {
                ship->CycleSecondary();
                WeaponGroup* m = ship->GetSecondaryGroup();

                while (m != current_missile && m != best) {
                    ship->CycleSecondary();
                    m = ship->GetSecondaryGroup();
                }
            }
        }

        else {
            winchester[wix] = true;

            // if we have NO weapons that can hit this target,
            // just drop it:

            Weapon* primary = ship->GetPrimary();
            if (!primary || !primary->CanTarget(tgt->Class())) {
                ship_ai->DropTarget(3);
                ship->DropTarget();
            }
        }

        if (tgt->IsGroundUnit())
        ship->SetSensorMode(Sensor::GM);

        else if (ship->GetSensorMode() == Sensor::GM)
        ship->SetSensorMode(Sensor::STD);
    }
}

// +--------------------------------------------------------------------+

void
FighterTacticalAI::FindFormationSlot(int formation)
{
    // find the formation delta:
    int s = element_index - 1;
    Point delta(5*s, 0, -5*s);

    // diamond:
    if (formation == Instruction::DIAMOND) {
        switch (element_index) {
        case 2:  delta = Point( 12, -1, -10); break;
        case 3:  delta = Point(-12, -1, -10); break;
        case 4:  delta = Point(  0, -2, -20); break;
        }
    }

    // spread:
    if (formation == Instruction::SPREAD) {
        switch (element_index) {
        case 2:  delta = Point( 15, 0, 0); break;
        case 3:  delta = Point(-15, 0, 0); break;
        case 4:  delta = Point(-30, 0, 0); break;
        }
    }

    // box:
    if (formation == Instruction::BOX) {
        switch (element_index) {
        case 2:  delta = Point(15,  0,   0); break;
        case 3:  delta = Point( 0, -2, -20); break;
        case 4:  delta = Point(15, -2, -20); break;
        }
    }

    // trail:
    if (formation == Instruction::TRAIL) {
        delta = Point(0, s, -20*s);
    }

    ship_ai->SetFormationDelta(delta * ship->Radius() * 2);
}

// +--------------------------------------------------------------------+

void
FighterTacticalAI::FindThreat()
{
    // pick the closest contact on Threat Warning System:
    Ship*       threat_ship          = 0;
    Shot*       threat_missile       = 0;
    double      threat_dist          = 1e9;

    ListIter<Contact> c_iter = ship->ContactList();

    while (++c_iter) {
        Contact* contact = c_iter.value();

        if (contact->Threat(ship) &&
                (Game::GameTime() - contact->AcquisitionTime()) > THREAT_REACTION_TIME) {

            double rng = contact->Range(ship);

            if (contact->GetShot()) {
                threat_missile = contact->GetShot();
            }

            else if (rng < threat_dist && contact->GetShip()) {
                Ship* candidate = contact->GetShip();

                if (candidate->InTransition())
                continue;

                if (candidate->IsStarship() && rng < 50e3) {
                    threat_ship = candidate;
                    threat_dist = rng;
                }

                else if (candidate->IsDropship() && rng < 25e3) {
                    threat_ship = candidate;
                    threat_dist = rng;
                }

                // static and ground units:
                else if (rng < 30e3) {
                    threat_ship = candidate;
                    threat_dist = rng;
                }
            }
        }
    }

    ship_ai->SetThreat(threat_ship);
    ship_ai->SetThreatMissile(threat_missile);
}

// +--------------------------------------------------------------------+

bool
FighterTacticalAI::IsStrikeComplete(Instruction* instr)
{
    // wingmen can not call a halt to a strike:
    if (!ship || element_index > 1)
    return false;

    // if there's nothing to shoot at, we must be done:
    if (!instr || !instr->GetTarget() || instr->GetTarget()->Life() == 0 ||
            instr->GetTarget()->Type() != SimObject::SIM_SHIP)
    return true;

    // break off strike only when ALL weapons are expended:
    // (remember to check all relevant wingmen)
    Element*    element = ship->GetElement();
    Ship*       target  = (Ship*) instr->GetTarget();

    if (!element)
    return true;

    for (int i = 0; i < element->NumShips(); i++) {
        Ship* s = element->GetShip(i+1);

        if (!s || s->Integrity() < 25) // || (s->Location() - target->Location()).length() > 250e3)
        continue;

        ListIter<WeaponGroup> g_iter = s->Weapons();
        while (++g_iter) {
            WeaponGroup* w = g_iter.value();

            if (w->Ammo() && w->CanTarget(target->Class())) {
                ListIter<Weapon> w_iter = w->GetWeapons();

                while (++w_iter) {
                    Weapon* weapon = w_iter.value();

                    if (weapon->Status() > System::CRITICAL)
                    return false;
                }
            }
        }
    }

    // still here?  we must be done!
    return true;
}