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 #include <glm/gtx/vector_angle.hpp>
  23
  24 #include <iostream>
  25 #include <glm/gtx/io.hpp>
  26
  27
  28 namespace blobs {
  29 namespace creature {
  30
  31 Creature::Creature(world::Simulation &sim)
  32 : sim(sim)
  33 , name()
  34 , genome()
  35 , properties()
  36 , cur_prop(0)
  37 , base_color(1.0)
  38 , highlight_color(0.0)
  39 , mass(1.0)
  40 , density(1.0)
  41 , size(1.0)
  42 , birth(sim.Time())
  43 , health(1.0)
  44 , on_death()
  45 , removable(false)
  46 , memory(*this)
  47 , needs()
  48 , goals()
  49 , situation()
  50 , steering()
  51 , vao() {
  52 }
  53
  54 Creature::~Creature() {
  55 }
  56
  57 glm::dvec4 Creature::HighlightColor() const noexcept {
  58         return glm::dvec4(highlight_color, AgeLerp(CurProps().highlight, NextProps().highlight));
  59 }
  60
  61 void Creature::Ingest(int res, double amount) noexcept {
  62         const Genome::Composition *cmp = nullptr;
  63         for (const auto &c : genome.composition) {
  64                 if (c.resource == res) {
  65                         cmp = &c;
  66                         break;
  67                 }
  68         }
  69         if (cmp) {
  70                 const double max_mass = AgeLerp(CurProps().mass, NextProps().mass);
  71                 Mass(std::min(max_mass, mass + amount));
  72         } else {
  73                 // foreign material. poisonous?
  74         }
  75 }
  76
  77 void Creature::Hurt(double dt) noexcept {
  78         health = std::max(0.0, health - dt);
  79         if (health == 0.0) {
  80                 std::cout << "[" << int(sim.Time()) << "s] "
  81                 << name << " died" << std::endl;
  82                 Die();
  83         }
  84 }
  85
  86 void Creature::Die() noexcept {
  87         needs.clear();
  88         goals.clear();
  89         steering.Halt();
  90         if (on_death) {
  91                 on_death(*this);
  92         }
  93         Remove();
  94 }
  95
  96 double Creature::Size() const noexcept {
  97         return size;
  98 }
  99
 100 double Creature::Age() const noexcept {
 101         return sim.Time() - birth;
 102 }
 103
 104 std::string Creature::AgeName() const {
 105         switch (cur_prop) {
 106                 case 0:
 107                         return "Newborn";
 108                 case 1:
 109                         return "Child";
 110                 case 2:
 111                         return "Youth";
 112                 case 3:
 113                         return "Adult";
 114                 case 4:
 115                         return "Elder";
 116                 case 5:
 117                         return "Dead";
 118                 default:
 119                         return "Unknown";
 120         }
 121 }
 122
 123 double Creature::AgeLerp(double from, double to) const noexcept {
 124         return glm::mix(from, to, glm::smoothstep(CurProps().age, NextProps().age, Age()));
 125 }
 126
 127 double Creature::Fertility() const noexcept {
 128         return AgeLerp(CurProps().fertility, NextProps().fertility) / 3600.0;
 129 }
 130
 131 void Creature::AddGoal(std::unique_ptr<Goal> &&g) {
 132         std::cout << "[" << int(sim.Time()) << "s] " << name << " new goal: " << g->Describe() << std::endl;
 133         g->Enable();
 134         goals.emplace_back(std::move(g));
 135 }
 136
 137 namespace {
 138
 139 bool GoalCompare(const std::unique_ptr<Goal> &a, const std::unique_ptr<Goal> &b) {
 140         return b->Urgency() < a->Urgency();
 141 }
 142
 143 }
 144
 145 void Creature::Tick(double dt) {
 146         if (cur_prop < 5 && Age() > NextProps().age) {
 147                 ++cur_prop;
 148                 if (cur_prop == 5) {
 149                         std::cout << "[" << int(sim.Time()) << "s] "
 150                                 << name << " died of old age" << std::endl;
 151                         Die();
 152                 }
 153         }
 154
 155         {
 156                 Situation::State state(situation.GetState());
 157                 Situation::Derivative a(Step(Situation::Derivative(), 0.0));
 158                 Situation::Derivative b(Step(a, dt * 0.5));
 159                 Situation::Derivative c(Step(b, dt * 0.5));
 160                 Situation::Derivative d(Step(c, dt));
 161                 Situation::Derivative f(
 162                         (1.0 / 6.0) * (a.vel + 2.0 * (b.vel + c.vel) + d.vel),
 163                         (1.0 / 6.0) * (a.acc + 2.0 * (b.acc + c.acc) + d.acc),
 164                         (1.0 / 6.0) * (a.turn + 2.0 * (b.turn + c.turn) + d.turn)
 165                 );
 166                 state.pos += f.vel * dt;
 167                 state.vel += f.acc * dt;
 168                 constexpr double turn_speed = 10.0;
 169                 state.dir = glm::normalize(state.dir + f.turn * turn_speed * dt);
 170                 situation.SetState(state);
 171         }
 172
 173         memory.Tick(dt);
 174         for (auto &need : needs) {
 175                 need->Tick(dt);
 176         }
 177         for (auto &goal : goals) {
 178                 goal->Tick(dt);
 179         }
 180         // do background stuff
 181         for (auto &need : needs) {
 182                 need->ApplyEffect(*this, dt);
 183         }
 184         if (goals.empty()) {
 185                 return;
 186         }
 187         // if active goal can be interrupted, check priorities
 188         if (goals.size() > 1 && goals[0]->Interruptible()) {
 189                 std::sort(goals.begin(), goals.end(), GoalCompare);
 190         }
 191         goals[0]->Action();
 192         for (auto goal = goals.begin(); goal != goals.end();) {
 193                 if ((*goal)->Complete()) {
 194                         goals.erase(goal);
 195                 } else {
 196                         ++goal;
 197                 }
 198         }
 199 }
 200
 201 Situation::Derivative Creature::Step(const Situation::Derivative &ds, double dt) const noexcept {
 202         Situation::State s = situation.GetState();
 203         s.pos += ds.vel * dt;
 204         s.vel += ds.acc * dt;
 205         s.dir = normalize(s.dir + ds.turn * dt);
 206         return {
 207                 s.vel,
 208                 steering.Acceleration(s),
 209                 allzero(s.vel) ? glm::dvec3(0.0) : normalize(s.vel) - s.dir
 210         };
 211 }
 212
 213 glm::dmat4 Creature::LocalTransform() noexcept {
 214         // TODO: surface transform
 215         const double half_size = size * 0.5;
 216         const glm::dvec3 &pos = situation.Position();
 217         return glm::translate(glm::dvec3(pos.x, pos.y, pos.z + half_size))
 218                 * glm::dmat4(world::Planet::SurfaceOrientation(situation.Surface()))
 219                 * glm::rotate(glm::orientedAngle(glm::dvec3(0.0, 0.0, -1.0), situation.Heading(), glm::dvec3(0.0, 1.0, 0.0)), glm::dvec3(0.0, 1.0, 0.0))
 220                 * glm::scale(glm::dvec3(half_size, half_size, half_size));
 221 }
 222
 223 void Creature::BuildVAO() {
 224         vao.Bind();
 225         vao.BindAttributes();
 226         vao.EnableAttribute(0);
 227         vao.EnableAttribute(1);
 228         vao.EnableAttribute(2);
 229         vao.AttributePointer<glm::vec3>(0, false, offsetof(Attributes, position));
 230         vao.AttributePointer<glm::vec3>(1, false, offsetof(Attributes, normal));
 231         vao.AttributePointer<glm::vec3>(2, false, offsetof(Attributes, texture));
 232         vao.ReserveAttributes(6 * 4, GL_STATIC_DRAW);
 233         {
 234                 auto attrib = vao.MapAttributes(GL_WRITE_ONLY);
 235                 const float offset = 1.0f;
 236                 for (int surface = 0; surface < 6; ++surface) {
 237                         const float tex_u_begin = surface < 3 ? 1.0f : 0.0f;
 238                         const float tex_u_end = surface < 3 ? 0.0f : 1.0f;
 239
 240                         attrib[4 * surface + 0].position[(surface + 0) % 3] = -offset;
 241                         attrib[4 * surface + 0].position[(surface + 1) % 3] = -offset;
 242                         attrib[4 * surface + 0].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 243                         attrib[4 * surface + 0].normal[(surface + 0) % 3] = 0.0f;
 244                         attrib[4 * surface + 0].normal[(surface + 1) % 3] = 0.0f;
 245                         attrib[4 * surface + 0].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 246                         attrib[4 * surface + 0].texture.x = tex_u_begin;
 247                         attrib[4 * surface + 0].texture.y = 1.0f;
 248                         attrib[4 * surface + 0].texture.z = surface;
 249
 250                         attrib[4 * surface + 1].position[(surface + 0) % 3] = -offset;
 251                         attrib[4 * surface + 1].position[(surface + 1) % 3] =  offset;
 252                         attrib[4 * surface + 1].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 253                         attrib[4 * surface + 1].normal[(surface + 0) % 3] = 0.0f;
 254                         attrib[4 * surface + 1].normal[(surface + 1) % 3] = 0.0f;
 255                         attrib[4 * surface + 1].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 256                         attrib[4 * surface + 1].texture.x = tex_u_end;
 257                         attrib[4 * surface + 1].texture.y = 1.0f;
 258                         attrib[4 * surface + 1].texture.z = surface;
 259
 260                         attrib[4 * surface + 2].position[(surface + 0) % 3] =  offset;
 261                         attrib[4 * surface + 2].position[(surface + 1) % 3] = -offset;
 262                         attrib[4 * surface + 2].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 263                         attrib[4 * surface + 2].normal[(surface + 0) % 3] = 0.0f;
 264                         attrib[4 * surface + 2].normal[(surface + 1) % 3] = 0.0f;
 265                         attrib[4 * surface + 2].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 266                         attrib[4 * surface + 2].texture.x = tex_u_begin;
 267                         attrib[4 * surface + 2].texture.y = 0.0f;
 268                         attrib[4 * surface + 2].texture.z = surface;
 269
 270                         attrib[4 * surface + 3].position[(surface + 0) % 3] = offset;
 271                         attrib[4 * surface + 3].position[(surface + 1) % 3] = offset;
 272                         attrib[4 * surface + 3].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 273                         attrib[4 * surface + 3].normal[(surface + 0) % 3] = 0.0f;
 274                         attrib[4 * surface + 3].normal[(surface + 1) % 3] = 0.0f;
 275                         attrib[4 * surface + 3].normal[(surface + 2) % 3] = surface < 3 ? 1.0f : -1.0f;
 276                         attrib[4 * surface + 3].texture.x = tex_u_end;
 277                         attrib[4 * surface + 3].texture.y = 0.0f;
 278                         attrib[4 * surface + 3].texture.z = surface;
 279                 }
 280         }
 281         vao.BindElements();
 282         vao.ReserveElements(6 * 6, GL_STATIC_DRAW);
 283         {
 284                 auto element = vao.MapElements(GL_WRITE_ONLY);
 285                 for (int surface = 0; surface < 3; ++surface) {
 286                         element[6 * surface + 0] = 4 * surface + 0;
 287                         element[6 * surface + 1] = 4 * surface + 2;
 288                         element[6 * surface + 2] = 4 * surface + 1;
 289                         element[6 * surface + 3] = 4 * surface + 1;
 290                         element[6 * surface + 4] = 4 * surface + 2;
 291                         element[6 * surface + 5] = 4 * surface + 3;
 292                 }
 293                 for (int surface = 3; surface < 6; ++surface) {
 294                         element[6 * surface + 0] = 4 * surface + 0;
 295                         element[6 * surface + 1] = 4 * surface + 1;
 296                         element[6 * surface + 2] = 4 * surface + 2;
 297                         element[6 * surface + 3] = 4 * surface + 2;
 298                         element[6 * surface + 4] = 4 * surface + 1;
 299                         element[6 * surface + 5] = 4 * surface + 3;
 300                 }
 301         }
 302         vao.Unbind();
 303 }
 304
 305 void Creature::Draw(graphics::Viewport &viewport) {
 306         vao.Bind();
 307         vao.DrawTriangles(6 * 6);
 308 }
 309
 310
 311 void Spawn(Creature &c, world::Planet &p) {
 312         p.AddCreature(&c);
 313         c.GetSituation().SetPlanetSurface(p, 0, p.TileCenter(0, p.SideLength() / 2, p.SideLength() / 2));
 314
 315         // probe surrounding area for common resources
 316         int start = p.SideLength() / 2 - 2;
 317         int end = start + 5;
 318         std::map<int, double> yields;
 319         for (int y = start; y < end; ++y) {
 320                 for (int x = start; x < end; ++x) {
 321                         const world::TileType &t = p.TypeAt(0, x, y);
 322                         for (auto yield : t.resources) {
 323                                 yields[yield.resource] += yield.ubiquity;
 324                         }
 325                 }
 326         }
 327         int liquid = -1;
 328         int solid = -1;
 329         for (auto e : yields) {
 330                 if (c.GetSimulation().Resources()[e.first].state == world::Resource::LIQUID) {
 331                         if (liquid < 0 || e.second > yields[liquid]) {
 332                                 liquid = e.first;
 333                         }
 334                 } else if (c.GetSimulation().Resources()[e.first].state == world::Resource::SOLID) {
 335                         if (solid < 0 || e.second > yields[solid]) {
 336                                 solid = e.first;
 337                         }
 338                 }
 339         }
 340
 341         Genome genome;
 342
 343         genome.properties.Birth().age = { 0.0, 0.0 };
 344         genome.properties.Birth().mass = { 0.5, 0.05 };
 345         genome.properties.Birth().fertility = { 0.0, 0.0 };
 346         genome.properties.Birth().highlight = { 0.0, 0.0 };
 347
 348         genome.properties.Child().age = { 30.0, 1.0 };
 349         genome.properties.Child().mass = { 0.7, 0.05 };
 350         genome.properties.Child().fertility = { 0.0, 0.0 };
 351         genome.properties.Child().highlight = { 0.2, 0.05 };
 352
 353         genome.properties.Youth().age = { 60.0, 5.0 };
 354         genome.properties.Youth().mass = { 0.9, 0.1 };
 355         genome.properties.Youth().fertility = { 0.5, 0.03 };
 356         genome.properties.Youth().highlight = { 0.9, 0.1 };
 357
 358         genome.properties.Adult().age = { 120.0, 10.0 };
 359         genome.properties.Adult().mass = { 1.2, 0.1 };
 360         genome.properties.Adult().fertility = { 0.4, 0.01 };
 361         genome.properties.Adult().highlight = { 0.7, 0.1 };
 362
 363         genome.properties.Elder().age = { 360.0, 30.0 };
 364         genome.properties.Elder().mass = { 1.0, 0.05 };
 365         genome.properties.Elder().fertility = { 0.1, 0.01 };
 366         genome.properties.Elder().highlight = { 0.6, 0.1 };
 367
 368         genome.properties.Death().age = { 480.0, 60.0 };
 369         genome.properties.Death().mass = { 0.9, 0.05 };
 370         genome.properties.Death().fertility = { 0.0, 0.0 };
 371         genome.properties.Death().highlight = { 0.5, 0.1 };
 372
 373         genome.properties.strength = { 1.0, 0.1 };
 374         genome.properties.stamina = { 1.0, 0.1 };
 375         genome.properties.dexerty = { 1.0, 0.1 };
 376         genome.properties.intelligence = { 1.0, 0.1 };
 377         genome.properties.mutability = { 1.0, 0.1 };
 378
 379         glm::dvec3 color_avg(0.0);
 380         double color_divisor = 0.0;
 381
 382         if (p.HasAtmosphere()) {
 383                 genome.composition.push_back({
 384                         p.Atmosphere(),    // resource
 385                         { 0.01, 0.00001 }, // mass
 386                         { 0.5,  0.001 },   // intake
 387                         { 0.1,  0.0005 },  // penalty
 388                         { 0.0,  0.0 },     // growth
 389                 });
 390                 color_avg += c.GetSimulation().Resources()[p.Atmosphere()].base_color * 0.1;
 391                 color_divisor += 0.1;
 392         }
 393         if (liquid > -1) {
 394                 genome.composition.push_back({
 395                         liquid,          // resource
 396                         { 0.6,  0.01 },  // mass
 397                         { 0.2,  0.001 }, // intake
 398                         { 0.01, 0.002 }, // penalty
 399                         { 0.1, 0.0 },   // growth
 400                 });
 401                 color_avg += c.GetSimulation().Resources()[liquid].base_color * 0.5;
 402                 color_divisor += 0.5;
 403         }
 404         if (solid > -1) {
 405                 genome.composition.push_back({
 406                         solid,             // resource
 407                         { 0.4,   0.01 },   // mass
 408                         { 0.4,   0.001 },  // intake
 409                         { 0.001, 0.0001 }, // penalty
 410                         { 10.0,  0.002 },   // growth
 411                 });
 412                 color_avg += c.GetSimulation().Resources()[solid].base_color;
 413                 color_divisor += 1.0;
 414         }
 415
 416         if (color_divisor > 0.001) {
 417                 color_avg /= color_divisor;
 418         }
 419         glm::dvec3 hsl = rgb2hsl(color_avg);
 420         genome.base_hue = { hsl.x, 0.01 };
 421         genome.base_saturation = { hsl.y, 0.01 };
 422         genome.base_lightness = { hsl.z, 0.01 };
 423
 424         genome.Configure(c);
 425 }
 426
 427 void Genome::Configure(Creature &c) const {
 428         c.GetGenome() = *this;
 429
 430         math::GaloisLFSR &random = c.GetSimulation().Assets().random;
 431
 432         c.GetProperties() = Instantiate(properties, random);
 433
 434         double mass = 0.0;
 435         double volume = 0.0;
 436         for (const auto &comp : composition) {
 437                 const world::Resource &resource = c.GetSimulation().Resources()[comp.resource];
 438                 double comp_mass = comp.mass.FakeNormal(random.SNorm());
 439                 double intake = comp.intake.FakeNormal(random.SNorm());
 440                 double penalty = comp.penalty.FakeNormal(random.SNorm());
 441
 442                 mass += comp_mass;
 443                 volume += comp_mass / c.GetSimulation().Resources()[comp.resource].density;
 444
 445                 std::unique_ptr<Need> need;
 446                 if (resource.state == world::Resource::SOLID) {
 447                         intake *= std::atan(c.GetProperties().strength);
 448                         need.reset(new IngestNeed(comp.resource, intake, penalty));
 449                         need->gain = intake * 0.05;
 450                 } else if (resource.state == world::Resource::LIQUID) {
 451                         intake *= std::atan(c.GetProperties().stamina);
 452                         need.reset(new IngestNeed(comp.resource, intake, penalty));
 453                         need->gain = intake * 0.1;
 454                 } else {
 455                         need.reset(new InhaleNeed(comp.resource, intake, penalty));
 456                         need->gain = intake * 0.5;
 457                 }
 458                 need->name = c.GetSimulation().Resources()[comp.resource].label;
 459                 need->inconvenient = 0.5;
 460                 need->critical = 0.95;
 461                 c.AddNeed(std::move(need));
 462         }
 463
 464         glm::dvec3 base_color(
 465                 std::fmod(base_hue.FakeNormal(random.SNorm()) + 1.0, 1.0),
 466                 glm::clamp(base_saturation.FakeNormal(random.SNorm()), 0.0, 1.0),
 467                 glm::clamp(base_lightness.FakeNormal(random.SNorm()), 0.0, 1.0)
 468         );
 469         glm::dvec3 highlight_color(
 470                 std::fmod(base_color.x + 0.5, 1.0),
 471                 1.0 - base_color.y,
 472                 1.0 - base_color.z
 473         );
 474         c.BaseColor(hsl2rgb(base_color));
 475         c.HighlightColor(hsl2rgb(highlight_color));
 476
 477         c.Mass(c.GetProperties().props[0].mass);
 478         c.Density(mass / volume);
 479         c.GetSteering().MaxAcceleration(1.4 * std::atan(c.GetProperties().strength));
 480         c.GetSteering().MaxSpeed(4.4 * std::atan(c.GetProperties().dexerty));
 481         c.AddGoal(std::unique_ptr<Goal>(new IdleGoal(c)));
 482 }
 483
 484
 485 void Split(Creature &c) {
 486         Creature *a = new Creature(c.GetSimulation());
 487         const Situation &s = c.GetSituation();
 488         a->Name(c.GetSimulation().Assets().name.Sequential());
 489         // TODO: mutate
 490         c.GetGenome().Configure(*a);
 491         s.GetPlanet().AddCreature(a);
 492         // TODO: duplicate situation somehow
 493         a->GetSituation().SetPlanetSurface(
 494                 s.GetPlanet(), s.Surface(),
 495                 s.Position() + glm::dvec3(0.0, a->Size() * 0.51, 0.0));
 496         a->BuildVAO();
 497
 498         Creature *b = new Creature(c.GetSimulation());
 499         b->Name(c.GetSimulation().Assets().name.Sequential());
 500         c.GetGenome().Configure(*b);
 501         s.GetPlanet().AddCreature(b);
 502         b->GetSituation().SetPlanetSurface(
 503                 s.GetPlanet(), s.Surface(),
 504                 s.Position() + glm::dvec3(0.0, b->Size() * -0.51, 0.0));
 505         b->BuildVAO();
 506
 507         c.Die();
 508 }
 509
 510
 511 Memory::Memory(Creature &c)
 512 : c(c) {
 513 }
 514
 515 Memory::~Memory() {
 516 }
 517
 518 void Memory::Tick(double dt) {
 519         Situation &s = c.GetSituation();
 520         if (s.OnSurface()) {
 521                 TrackStay({ &s.GetPlanet(), s.Surface(), s.SurfacePosition() }, dt);
 522         }
 523 }
 524
 525 void Memory::TrackStay(const Location &l, double t) {
 526         const world::TileType &type = l.planet->TypeAt(l.surface, l.coords.x, l.coords.y);
 527         auto entry = known_types.find(type.id);
 528         if (entry != known_types.end()) {
 529                 entry->second.last_been = c.GetSimulation().Time();
 530                 entry->second.last_loc = l;
 531                 entry->second.time_spent += t;
 532         } else {
 533                 known_types.emplace(type.id, Stay{
 534                         c.GetSimulation().Time(),
 535                         l,
 536                         c.GetSimulation().Time(),
 537                         l,
 538                         t
 539                 });
 540         }
 541 }
 542
 543
 544 NameGenerator::NameGenerator()
 545 : counter(0) {
 546 }
 547
 548 NameGenerator::~NameGenerator() {
 549 }
 550
 551 std::string NameGenerator::Sequential() {
 552         std::stringstream ss;
 553         ss << "Blob " << ++counter;
 554         return ss.str();
 555 }
 556
 557
 558 Situation::Situation()
 559 : planet(nullptr)
 560 , state(glm::dvec3(0.0), glm::dvec3(0.0))
 561 , surface(0)
 562 , type(LOST) {
 563 }
 564
 565 Situation::~Situation() {
 566 }
 567
 568 bool Situation::OnPlanet() const noexcept {
 569         return type == PLANET_SURFACE;
 570 }
 571
 572 bool Situation::OnSurface() const noexcept {
 573         return type == PLANET_SURFACE;
 574 }
 575
 576 bool Situation::OnTile() const noexcept {
 577         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 578         return type == PLANET_SURFACE
 579                 && t.x >= 0 && t.x < planet->SideLength()
 580                 && t.y >= 0 && t.y < planet->SideLength();
 581 }
 582
 583 glm::ivec2 Situation::SurfacePosition() const noexcept {
 584         return planet->SurfacePosition(surface, state.pos);
 585 }
 586
 587 world::Tile &Situation::GetTile() const noexcept {
 588         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 589         return planet->TileAt(surface, t.x, t.y);
 590 }
 591
 592 const world::TileType &Situation::GetTileType() const noexcept {
 593         glm::ivec2 t(planet->SurfacePosition(surface, state.pos));
 594         return planet->TypeAt(surface, t.x, t.y);
 595 }
 596
 597 void Situation::Move(const glm::dvec3 &dp) noexcept {
 598         state.pos += dp;
 599         if (OnSurface()) {
 600                 // enforce ground constraint
 601                 if (Surface() < 3) {
 602                         state.pos[(Surface() + 2) % 3] = std::max(0.0, state.pos[(Surface() + 2) % 3]);
 603                 } else {
 604                         state.pos[(Surface() + 2) % 3] = std::min(0.0, state.pos[(Surface() + 2) % 3]);
 605                 }
 606         }
 607 }
 608
 609 void Situation::SetPlanetSurface(world::Planet &p, int srf, const glm::dvec3 &pos) noexcept {
 610         type = PLANET_SURFACE;
 611         planet = &p;
 612         surface = srf;
 613         state.pos = pos;
 614 }
 615
 616
 617 Steering::Steering()
 618 : target(0.0)
 619 , max_accel(1.0)
 620 , max_speed(1.0)
 621 , halting(false)
 622 , seeking(false)
 623 , arriving(false) {
 624 }
 625
 626 Steering::~Steering() {
 627 }
 628
 629 void Steering::Halt() noexcept {
 630         halting = true;
 631         seeking = false;
 632         arriving = false;
 633 }
 634
 635 void Steering::Pass(const glm::dvec3 &t) noexcept {
 636         target = t;
 637         halting = false;
 638         seeking = true;
 639         arriving = false;
 640 }
 641
 642 void Steering::GoTo(const glm::dvec3 &t) noexcept {
 643         target = t;
 644         halting = false;
 645         seeking = false;
 646         arriving = true;
 647 }
 648
 649 glm::dvec3 Steering::Acceleration(const Situation::State &s) const noexcept {
 650         glm::dvec3 acc(0.0);
 651         if (halting) {
 652                 SumForce(acc, s.vel * -max_accel);
 653         }
 654         if (seeking) {
 655                 glm::dvec3 diff = target - s.pos;
 656                 if (!allzero(diff)) {
 657                         SumForce(acc, TargetVelocity(s, (normalize(diff) * max_speed)));
 658                 }
 659         }
 660         if (arriving) {
 661                 glm::dvec3 diff = target - s.pos;
 662                 double dist = length(diff);
 663                 if (!allzero(diff) && dist > std::numeric_limits<double>::epsilon()) {
 664                         SumForce(acc, TargetVelocity(s, diff * std::min(dist * max_accel, max_speed) / dist));
 665                 }
 666         }
 667         return acc;
 668 }
 669
 670 bool Steering::SumForce(glm::dvec3 &out, const glm::dvec3 &in) const noexcept {
 671         if (allzero(in) || anynan(in)) {
 672                 return false;
 673         }
 674         double cur = allzero(out) ? 0.0 : length(out);
 675         double rem = max_accel - cur;
 676         if (rem < 0.0) {
 677                 return true;
 678         }
 679         double add = length(in);
 680         if (add > rem) {
 681                 // this method is off if in and out are in different
 682                 // directions, but gives okayish results
 683                 out += in * (1.0 / add);
 684                 return true;
 685         } else {
 686                 out += in;
 687                 return false;
 688         }
 689 }
 690
 691 glm::dvec3 Steering::TargetVelocity(const Situation::State &s, const glm::dvec3 &vel) const noexcept {
 692         return (vel - s.vel) * max_accel;
 693 }
 694
 695 }
 696 }