src/creature/creature.cpp

   1 #include "Creature.hpp"
   2 #include "Genome.hpp"
   3 #include "Memory.hpp"
   4 #include "NameGenerator.hpp"
   5 #include "Situation.hpp"
   6 #include "Steering.hpp"
   7
   8 #include "Goal.hpp"
   9 #include "IdleGoal.hpp"
  10 #include "InhaleNeed.hpp"
  11 #include "IngestNeed.hpp"
  12 #include "Need.hpp"
  13 #include "../app/Assets.hpp"
  14 #include "../world/Body.hpp"
  15 #include "../world/Planet.hpp"
  16 #include "../world/Simulation.hpp"
  17 #include "../world/TileType.hpp"
  18
  19 #include <algorithm>
  20 #include <sstream>
  21 #include <glm/gtx/transform.hpp>
  22
  23 #include <iostream>
  24 #include <glm/gtx/io.hpp>
  25
  26
  27 namespace blobs {
  28 namespace creature {
  29
  30 Creature::Creature(world::Simulation &sim)
  31 : sim(sim)
  32 , name()
  33 , genome()
  34 , properties()
  35 , cur_prop(0)
  36 , base_color(1.0)
  37 , highlight_color(0.0)
  38 , mass(1.0)
  39 , density(1.0)
  40 , size(1.0)
  41 , birth(sim.Time())
  42 , health(1.0)
  43 , on_death()
  44 , removable(false)
  45 , memory(*this)
  46 , needs()
  47 , goals()
  48 , situation()
  49 , steering()
  50 , vao() {
  51 }
  52
  53 Creature::~Creature() {
  54 }
  55
  56 glm::dvec4 Creature::HighlightColor() const noexcept {
  57         return glm::dvec4(highlight_color, AgeLerp(CurProps().highlight, NextProps().highlight));
  58 }
  59
  60 void Creature::Grow(double amount) noexcept {
  61         const double max_mass = AgeLerp(CurProps().mass, NextProps().mass);
  62         Mass(std::min(max_mass, mass + amount));
  63 }
  64
  65 void Creature::Hurt(double dt) noexcept {
  66         health = std::max(0.0, health - dt);
  67         if (health == 0.0) {
  68                 std::cout << "[" << int(sim.Time()) << "s] "
  69                 << name << " died" << std::endl;
  70                 Die();
  71         }
  72 }
  73
  74 void Creature::Die() noexcept {
  75         needs.clear();
  76         goals.clear();
  77         steering.Halt();
  78         if (on_death) {
  79                 on_death(*this);
  80         }
  81         Remove();
  82 }
  83
  84 double Creature::Size() const noexcept {
  85         return size;
  86 }
  87
  88 double Creature::Age() const noexcept {
  89         return sim.Time() - birth;
  90 }
  91
  92 double Creature::AgeLerp(double from, double to) const noexcept {
  93         return glm::mix(from, to, glm::smoothstep(CurProps().age, NextProps().age, Age()));
  94 }
  95
  96 double Creature::Fertility() const noexcept {
  97         return AgeLerp(CurProps().fertility, NextProps().fertility) / 3600.0;
  98 }
  99
 100 void Creature::AddGoal(std::unique_ptr<Goal> &&g) {
 101         std::cout << "[" << int(sim.Time()) << "s] " << name << " new goal: " << g->Describe() << std::endl;
 102         g->Enable();
 103         goals.emplace_back(std::move(g));
 104 }
 105
 106 namespace {
 107
 108 bool GoalCompare(const std::unique_ptr<Goal> &a, const std::unique_ptr<Goal> &b) {
 109         return b->Urgency() < a->Urgency();
 110 }
 111
 112 }
 113
 114 void Creature::Tick(double dt) {
 115         if (cur_prop < 5 && Age() > properties.props[cur_prop + 1].age) {
 116                 if (cur_prop == 4) {
 117                         std::cout << "[" << int(sim.Time()) << "s] "
 118                                 << name << " died of old age" << std::endl;
 119                         Die();
 120                 } else {
 121                         ++cur_prop;
 122                 }
 123         }
 124
 125         {
 126                 Situation::State state(situation.GetState());
 127                 Situation::Derivative a(Step(Situation::Derivative(), 0.0));
 128                 Situation::Derivative b(Step(a, dt * 0.5));
 129                 Situation::Derivative c(Step(b, dt * 0.5));
 130                 Situation::Derivative d(Step(c, dt));
 131                 Situation::Derivative f(
 132                         (1.0 / 6.0) * (a.vel + 2.0 * (b.vel + c.vel) + d.vel),
 133                         (1.0 / 6.0) * (a.acc + 2.0 * (b.acc + c.acc) + d.acc)
 134                 );
 135                 state.pos += f.vel * dt;
 136                 state.vel += f.acc * dt;
 137                 situation.SetState(state);
 138         }
 139
 140         memory.Tick(dt);
 141         for (auto &need : needs) {
 142                 need->Tick(dt);
 143         }
 144         for (auto &goal : goals) {
 145                 goal->Tick(dt);
 146         }
 147         // do background stuff
 148         for (auto &need : needs) {
 149                 need->ApplyEffect(*this, dt);
 150         }
 151         if (goals.empty()) {
 152                 return;
 153         }
 154         // if active goal can be interrupted, check priorities
 155         if (goals.size() > 1 && goals[0]->Interruptible()) {
 156                 Goal *old_top = &*goals[0];
 157                 std::sort(goals.begin(), goals.end(), GoalCompare);
 158                 Goal *new_top = &*goals[0];
 159                 if (new_top != old_top) {
 160                         std::cout << "[" << int(sim.Time()) << "s] " << name
 161                                 << " changing goal from " << old_top->Describe()
 162                                 << " to " << new_top->Describe() << std::endl;
 163                 }
 164         }
 165         goals[0]->Action();
 166         for (auto goal = goals.begin(); goal != goals.end();) {
 167                 if ((*goal)->Complete()) {
 168                         std::cout << "[" << int(sim.Time()) << "s] " << name
 169                                 << " complete goal: " << (*goal)->Describe() << std::endl;
 170                         goals.erase(goal);
 171                 } else {
 172                         ++goal;
 173                 }
 174         }
 175 }
 176
 177 Situation::Derivative Creature::Step(const Situation::Derivative &ds, double dt) const noexcept {
 178         Situation::State s = situation.GetState();
 179         s.pos += ds.vel * dt;
 180         s.vel += ds.acc * dt;
 181         return { s.vel, steering.Acceleration(s) };
 182 }
 183
 184 glm::dmat4 Creature::LocalTransform() noexcept {
 185         // TODO: surface transform
 186         const double half_size = size * 0.5;
 187         const glm::dvec3 &pos = situation.Position();
 188         return glm::translate(glm::dvec3(pos.x, pos.y, pos.z + half_size))
 189                 * glm::scale(glm::dvec3(half_size, half_size, half_size));
 190 }
 191
 192 void Creature::BuildVAO() {
 193         vao.Bind();
 194         vao.BindAttributes();
 195         vao.EnableAttribute(0);
 196         vao.EnableAttribute(1);
 197         vao.EnableAttribute(2);
 198         vao.AttributePointer<glm::vec3>(0, false, offsetof(Attributes, position));
 199         vao.AttributePointer<glm::vec3>(1, false, offsetof(Attributes, normal));
 200         vao.AttributePointer<glm::vec3>(2, false, offsetof(Attributes, texture));
 201         vao.ReserveAttributes(6 * 4, GL_STATIC_DRAW);
 202         {
 203                 auto attrib = vao.MapAttributes(GL_WRITE_ONLY);
 204                 const float offset = 1.0f;
 205                 for (int surface = 0; surface < 6; ++surface) {
 206                         const float tex_u_begin = surface < 3 ? 1.0f : 0.0f;
 207                         const float tex_u_end = surface < 3 ? 0.0f : 1.0f;
 208
 209                         attrib[4 * surface + 0].position[(surface + 0) % 3] = -offset;
 210                         attrib[4 * surface + 0].position[(surface + 1) % 3] = -offset;
 211                         attrib[4 * surface + 0].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 212                         attrib[4 * surface + 0].normal[(surface + 0) % 3] = 0.0f;
 213                         attrib[4 * surface + 0].normal[(surface + 1) % 3] = 0.0f;
 214                         attrib[4 * surface + 0].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 215                         attrib[4 * surface + 0].texture.x = tex_u_begin;
 216                         attrib[4 * surface + 0].texture.y = 1.0f;
 217                         attrib[4 * surface + 0].texture.z = surface;
 218
 219                         attrib[4 * surface + 1].position[(surface + 0) % 3] = -offset;
 220                         attrib[4 * surface + 1].position[(surface + 1) % 3] =  offset;
 221                         attrib[4 * surface + 1].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 222                         attrib[4 * surface + 1].normal[(surface + 0) % 3] = 0.0f;
 223                         attrib[4 * surface + 1].normal[(surface + 1) % 3] = 0.0f;
 224                         attrib[4 * surface + 1].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 225                         attrib[4 * surface + 1].texture.x = tex_u_end;
 226                         attrib[4 * surface + 1].texture.y = 1.0f;
 227                         attrib[4 * surface + 1].texture.z = surface;
 228
 229                         attrib[4 * surface + 2].position[(surface + 0) % 3] =  offset;
 230                         attrib[4 * surface + 2].position[(surface + 1) % 3] = -offset;
 231                         attrib[4 * surface + 2].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 232                         attrib[4 * surface + 2].normal[(surface + 0) % 3] = 0.0f;
 233                         attrib[4 * surface + 2].normal[(surface + 1) % 3] = 0.0f;
 234                         attrib[4 * surface + 2].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 235                         attrib[4 * surface + 2].texture.x = tex_u_begin;
 236                         attrib[4 * surface + 2].texture.y = 0.0f;
 237                         attrib[4 * surface + 2].texture.z = surface;
 238
 239                         attrib[4 * surface + 3].position[(surface + 0) % 3] = offset;
 240                         attrib[4 * surface + 3].position[(surface + 1) % 3] = offset;
 241                         attrib[4 * surface + 3].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 242                         attrib[4 * surface + 3].normal[(surface + 0) % 3] = 0.0f;
 243                         attrib[4 * surface + 3].normal[(surface + 1) % 3] = 0.0f;
 244                         attrib[4 * surface + 3].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 245                         attrib[4 * surface + 3].texture.x = tex_u_end;
 246                         attrib[4 * surface + 3].texture.y = 0.0f;
 247                         attrib[4 * surface + 3].texture.z = surface;
 248                 }
 249         }
 250         vao.BindElements();
 251         vao.ReserveElements(6 * 6, GL_STATIC_DRAW);
 252         {
 253                 auto element = vao.MapElements(GL_WRITE_ONLY);
 254                 for (int surface = 0; surface < 3; ++surface) {
 255                         element[6 * surface + 0] = 4 * surface + 0;
 256                         element[6 * surface + 1] = 4 * surface + 2;
 257                         element[6 * surface + 2] = 4 * surface + 1;
 258                         element[6 * surface + 3] = 4 * surface + 1;
 259                         element[6 * surface + 4] = 4 * surface + 2;
 260                         element[6 * surface + 5] = 4 * surface + 3;
 261                 }
 262                 for (int surface = 3; surface < 6; ++surface) {
 263                         element[6 * surface + 0] = 4 * surface + 0;
 264                         element[6 * surface + 1] = 4 * surface + 1;
 265                         element[6 * surface + 2] = 4 * surface + 2;
 266                         element[6 * surface + 3] = 4 * surface + 2;
 267                         element[6 * surface + 4] = 4 * surface + 1;
 268                         element[6 * surface + 5] = 4 * surface + 3;
 269                 }
 270         }
 271         vao.Unbind();
 272 }
 273
 274 void Creature::Draw(graphics::Viewport &viewport) {
 275         vao.Bind();
 276         vao.DrawTriangles(6 * 6);
 277 }
 278
 279
 280 void Spawn(Creature &c, world::Planet &p) {
 281         p.AddCreature(&c);
 282         c.GetSituation().SetPlanetSurface(p, 0, p.TileCenter(0, p.SideLength() / 2, p.SideLength() / 2));
 283
 284         // probe surrounding area for common resources
 285         int start = p.SideLength() / 2 - 2;
 286         int end = start + 5;
 287         std::map<int, double> yields;
 288         for (int y = start; y < end; ++y) {
 289                 for (int x = start; x < end; ++x) {
 290                         const world::TileType &t = p.TypeAt(0, x, y);
 291                         for (auto yield : t.resources) {
 292                                 yields[yield.resource] += yield.ubiquity;
 293                         }
 294                 }
 295         }
 296         int liquid = -1;
 297         int solid = -1;
 298         for (auto e : yields) {
 299                 if (c.GetSimulation().Resources()[e.first].state == world::Resource::LIQUID) {
 300                         if (liquid < 0 || e.second > yields[liquid]) {
 301                                 liquid = e.first;
 302                         }
 303                 } else if (c.GetSimulation().Resources()[e.first].state == world::Resource::SOLID) {
 304                         if (solid < 0 || e.second > yields[solid]) {
 305                                 solid = e.first;
 306                         }
 307                 }
 308         }
 309
 310         Genome genome;
 311
 312         genome.properties.Birth().age = { 0.0, 0.0 };
 313         genome.properties.Birth().mass = { 0.5, 0.05 };
 314         genome.properties.Birth().fertility = { 0.0, 0.0 };
 315         genome.properties.Birth().highlight = { 0.0, 0.0 };
 316
 317         genome.properties.Child().age = { 30.0, 1.0 };
 318         genome.properties.Child().mass = { 0.7, 0.05 };
 319         genome.properties.Child().fertility = { 0.0, 0.0 };
 320         genome.properties.Child().highlight = { 0.2, 0.05 };
 321
 322         genome.properties.Youth().age = { 60.0, 5.0 };
 323         genome.properties.Youth().mass = { 0.9, 0.1 };
 324         genome.properties.Youth().fertility = { 0.5, 0.03 };
 325         genome.properties.Youth().highlight = { 0.9, 0.1 };
 326
 327         genome.properties.Adult().age = { 120.0, 10.0 };
 328         genome.properties.Adult().mass = { 1.2, 0.1 };
 329         genome.properties.Adult().fertility = { 0.4, 0.01 };
 330         genome.properties.Adult().highlight = { 0.7, 0.1 };
 331
 332         genome.properties.Elder().age = { 360.0, 30.0 };
 333         genome.properties.Elder().mass = { 1.0, 0.05 };
 334         genome.properties.Elder().fertility = { 0.1, 0.01 };
 335         genome.properties.Elder().highlight = { 0.6, 0.1 };
 336
 337         genome.properties.Death().age = { 480.0, 60.0 };
 338         genome.properties.Death().mass = { 0.9, 0.05 };
 339         genome.properties.Death().fertility = { 0.0, 0.0 };
 340         genome.properties.Death().highlight = { 0.5, 0.1 };
 341
 342         glm::dvec3 color_avg(0.0);
 343         double color_divisor = 0.0;
 344
 345         if (p.HasAtmosphere()) {
 346                 genome.composition.push_back({
 347                         p.Atmosphere(),    // resource
 348                         { 0.01, 0.00001 }, // mass
 349                         { 0.5,  0.001 },   // intake
 350                         { 0.1,  0.0005 },  // penalty
 351                         { 0.0,  0.0 },     // growth
 352                 });
 353                 color_avg += c.GetSimulation().Resources()[p.Atmosphere()].base_color * 0.1;
 354                 color_divisor += 0.1;
 355         }
 356         if (liquid > -1) {
 357                 genome.composition.push_back({
 358                         liquid,          // resource
 359                         { 0.6,  0.01 },  // mass
 360                         { 0.2,  0.001 }, // intake
 361                         { 0.01, 0.002 }, // penalty
 362                         { 0.1, 0.0 },   // growth
 363                 });
 364                 color_avg += c.GetSimulation().Resources()[liquid].base_color * 0.5;
 365                 color_divisor += 0.5;
 366         }
 367         if (solid > -1) {
 368                 genome.composition.push_back({
 369                         solid,             // resource
 370                         { 0.4,   0.01 },   // mass
 371                         { 0.4,   0.001 },  // intake
 372                         { 0.001, 0.0001 }, // penalty
 373                         { 10.0,  0.002 },   // growth
 374                 });
 375                 color_avg += c.GetSimulation().Resources()[solid].base_color;
 376                 color_divisor += 1.0;
 377         }
 378
 379         if (color_divisor > 0.001) {
 380                 color_avg /= color_divisor;
 381         }
 382         glm::dvec3 hsl = rgb2hsl(color_avg);
 383         genome.base_hue = { hsl.x, 0.01 };
 384         genome.base_saturation = { hsl.y, 0.01 };
 385         genome.base_lightness = { hsl.z, 0.01 };
 386
 387         genome.Configure(c);
 388 }
 389
 390 void Genome::Configure(Creature &c) const {
 391         c.GetGenome() = *this;
 392
 393         math::GaloisLFSR &random = c.GetSimulation().Assets().random;
 394
 395         c.GetProperties() = Instantiate(properties, random);
 396
 397         double mass = 0.0;
 398         double volume = 0.0;
 399         for (const auto &comp : composition) {
 400                 double comp_mass = comp.mass.FakeNormal(random.SNorm());
 401                 double intake = comp.intake.FakeNormal(random.SNorm());
 402                 double penalty = comp.penalty.FakeNormal(random.SNorm());
 403
 404                 mass += comp_mass;
 405                 volume += comp_mass / c.GetSimulation().Resources()[comp.resource].density;
 406
 407                 std::unique_ptr<Need> need;
 408                 if (c.GetSimulation().Resources()[comp.resource].state == world::Resource::SOLID) {
 409                         need.reset(new IngestNeed(comp.resource, intake, penalty));
 410                         need->gain = intake * 0.05;
 411                 } else if (c.GetSimulation().Resources()[comp.resource].state == world::Resource::LIQUID) {
 412                         need.reset(new IngestNeed(comp.resource, intake, penalty));
 413                         need->gain = intake * 0.1;
 414                 } else {
 415                         need.reset(new InhaleNeed(comp.resource, intake, penalty));
 416                         need->gain = intake * 0.5;
 417                 }
 418                 need->name = c.GetSimulation().Resources()[comp.resource].label;
 419                 need->growth = comp.growth.FakeNormal(random.SNorm());
 420                 need->inconvenient = 0.5;
 421                 need->critical = 0.95;
 422                 c.AddNeed(std::move(need));
 423         }
 424
 425         glm::dvec3 base_color(
 426                 std::fmod(base_hue.FakeNormal(random.SNorm()) + 1.0, 1.0),
 427                 glm::clamp(base_saturation.FakeNormal(random.SNorm()), 0.0, 1.0),
 428                 glm::clamp(base_lightness.FakeNormal(random.SNorm()), 0.0, 1.0)
 429         );
 430         glm::dvec3 highlight_color(
 431                 std::fmod(base_color.x + 0.5, 1.0),
 432                 1.0 - base_color.y,
 433                 1.0 - base_color.z
 434         );
 435         c.BaseColor(hsl2rgb(base_color));
 436         c.HighlightColor(hsl2rgb(highlight_color));
 437
 438         c.Mass(c.GetProperties().props[0].mass);
 439         c.Density(mass / volume);
 440         c.GetSteering().MaxAcceleration(1.4);
 441         c.GetSteering().MaxSpeed(4.4);
 442         c.AddGoal(std::unique_ptr<Goal>(new IdleGoal(c)));
 443 }
 444
 445
 446 void Split(Creature &c) {
 447         Creature *a = new Creature(c.GetSimulation());
 448         const Situation &s = c.GetSituation();
 449         a->Name(c.GetSimulation().Assets().name.Sequential());
 450         // TODO: mutate
 451         c.GetGenome().Configure(*a);
 452         s.GetPlanet().AddCreature(a);
 453         // TODO: duplicate situation somehow
 454         a->GetSituation().SetPlanetSurface(
 455                 s.GetPlanet(), s.Surface(),
 456                 s.Position() + glm::dvec3(0.0, a->Size() * 0.51, 0.0));
 457         a->BuildVAO();
 458
 459         Creature *b = new Creature(c.GetSimulation());
 460         b->Name(c.GetSimulation().Assets().name.Sequential());
 461         c.GetGenome().Configure(*b);
 462         s.GetPlanet().AddCreature(b);
 463         b->GetSituation().SetPlanetSurface(
 464                 s.GetPlanet(), s.Surface(),
 465                 s.Position() + glm::dvec3(0.0, b->Size() * -0.51, 0.0));
 466         b->BuildVAO();
 467
 468         c.Die();
 469 }
 470
 471
 472 Memory::Memory(Creature &c)
 473 : c(c) {
 474 }
 475
 476 Memory::~Memory() {
 477 }
 478
 479 void Memory::Tick(double dt) {
 480         Situation &s = c.GetSituation();
 481         if (s.OnSurface()) {
 482                 TrackStay({ &s.GetPlanet(), s.Surface(), s.SurfacePosition() }, dt);
 483         }
 484 }
 485
 486 void Memory::TrackStay(const Location &l, double t) {
 487         const world::TileType &type = l.planet->TypeAt(l.surface, l.coords.x, l.coords.y);
 488         auto entry = known_types.find(type.id);
 489         if (entry != known_types.end()) {
 490                 entry->second.last_been = c.GetSimulation().Time();
 491                 entry->second.last_loc = l;
 492                 entry->second.time_spent += t;
 493         } else {
 494                 known_types.emplace(type.id, Stay{
 495                         c.GetSimulation().Time(),
 496                         l,
 497                         c.GetSimulation().Time(),
 498                         l,
 499                         t
 500                 });
 501         }
 502 }
 503
 504
 505 NameGenerator::NameGenerator()
 506 : counter(0) {
 507 }
 508
 509 NameGenerator::~NameGenerator() {
 510 }
 511
 512 std::string NameGenerator::Sequential() {
 513         std::stringstream ss;
 514         ss << "Blob " << ++counter;
 515         return ss.str();
 516 }
 517
 518
 519 Situation::Situation()
 520 : planet(nullptr)
 521 , state(glm::dvec3(0.0), glm::dvec3(0.0))
 522 , surface(0)
 523 , type(LOST) {
 524 }
 525
 526 Situation::~Situation() {
 527 }
 528
 529 bool Situation::OnPlanet() const noexcept {
 530         return type == PLANET_SURFACE;
 531 }
 532
 533 bool Situation::OnSurface() const noexcept {
 534         return type == PLANET_SURFACE;
 535 }
 536
 537 bool Situation::OnTile() const noexcept {
 538         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 539         return type == PLANET_SURFACE
 540                 && t.x >= 0 && t.x < planet->SideLength()
 541                 && t.y >= 0 && t.y < planet->SideLength();
 542 }
 543
 544 glm::ivec2 Situation::SurfacePosition() const noexcept {
 545         return planet->SurfacePosition(surface, state.pos);
 546 }
 547
 548 world::Tile &Situation::GetTile() const noexcept {
 549         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 550         return planet->TileAt(surface, t.x, t.y);
 551 }
 552
 553 const world::TileType &Situation::GetTileType() const noexcept {
 554         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 555         return planet->TypeAt(surface, t.x, t.y);
 556 }
 557
 558 void Situation::Move(const glm::dvec3 &dp) noexcept {
 559         state.pos += dp;
 560         if (OnSurface()) {
 561                 // enforce ground constraint
 562                 if (Surface() < 3) {
 563                         state.pos[(Surface() + 2) % 3] = std::max(0.0, state.pos[(Surface() + 2) % 3]);
 564                 } else {
 565                         state.pos[(Surface() + 2) % 3] = std::min(0.0, state.pos[(Surface() + 2) % 3]);
 566                 }
 567         }
 568 }
 569
 570 void Situation::SetPlanetSurface(world::Planet &p, int srf, const glm::dvec3 &pos) noexcept {
 571         type = PLANET_SURFACE;
 572         planet = &p;
 573         surface = srf;
 574         state.pos = pos;
 575 }
 576
 577
 578 Steering::Steering()
 579 : seek_target(0.0)
 580 , max_accel(1.0)
 581 , max_speed(1.0)
 582 , halting(false)
 583 , seeking(false) {
 584 }
 585
 586 Steering::~Steering() {
 587 }
 588
 589 void Steering::Halt() noexcept {
 590         halting = true;
 591         seeking = false;
 592 }
 593
 594 void Steering::GoTo(const glm::dvec3 &t) noexcept {
 595         seek_target = t;
 596         halting = false;
 597         seeking = true;
 598 }
 599
 600 glm::dvec3 Steering::Acceleration(const Situation::State &s) const noexcept {
 601         glm::dvec3 acc(0.0);
 602         if (halting) {
 603                 SumForce(acc, s.vel * -max_accel);
 604         }
 605         if (seeking) {
 606                 glm::dvec3 diff = seek_target - s.pos;
 607                 if (!allzero(diff)) {
 608                         SumForce(acc, ((normalize(diff) * max_speed) - s.vel) * max_accel);
 609                 }
 610         }
 611         return acc;
 612 }
 613
 614 bool Steering::SumForce(glm::dvec3 &out, const glm::dvec3 &in) const noexcept {
 615         if (allzero(in) || anynan(in)) {
 616                 return false;
 617         }
 618         double cur = allzero(out) ? 0.0 : length(out);
 619         double rem = max_accel - cur;
 620         if (rem < 0.0) {
 621                 return true;
 622         }
 623         double add = length(in);
 624         if (add > rem) {
 625                 // this method is off if in and out are in different
 626                 // directions, but gives okayish results
 627                 out += in * (1.0 / add);
 628                 return true;
 629         } else {
 630                 out += in;
 631                 return false;
 632         }
 633 }
 634
 635 }
 636 }