src/world/world.cpp

   1 #include "Body.hpp"
   2 #include "CreatureCreatureCollision.hpp"
   3 #include "Orbit.hpp"
   4 #include "Planet.hpp"
   5 #include "Resource.hpp"
   6 #include "Set.hpp"
   7 #include "Simulation.hpp"
   8 #include "Sun.hpp"
   9 #include "Tile.hpp"
  10 #include "TileType.hpp"
  11
  12 #include "../app/Assets.hpp"
  13 #include "../creature/Composition.hpp"
  14 #include "../creature/Creature.hpp"
  15 #include "../graphics/Viewport.hpp"
  16 #include "../math/const.hpp"
  17 #include "../math/geometry.hpp"
  18 #include "../math/OctaveNoise.hpp"
  19 #include "../math/SimplexNoise.hpp"
  20
  21 #include <algorithm>
  22 #include <cmath>
  23 #include <iostream>
  24 #include <glm/gtc/matrix_transform.hpp>
  25 #include <glm/gtx/euler_angles.hpp>
  26 #include <glm/gtx/io.hpp>
  27 #include <glm/gtx/transform.hpp>
  28
  29 using blobs::G;
  30 using blobs::PI_2p0;
  31
  32 using std::sin;
  33 using std::cos;
  34 using std::pow;
  35 using std::sqrt;
  36
  37
  38 namespace blobs {
  39 namespace world {
  40
  41 Body::Body()
  42 : sim(nullptr)
  43 , parent(nullptr)
  44 , children()
  45 , mass(1.0)
  46 , radius(1.0)
  47 , orbit()
  48 , surface_tilt(0.0, 0.0)
  49 , axis_tilt(0.0, 0.0)
  50 , rotation(0.0)
  51 , angular(0.0)
  52 , orbital(1.0)
  53 , inverse_orbital(1.0)
  54 , local(1.0)
  55 , inverse_local(1.0)
  56 , creatures()
  57 , atmosphere(-1) {
  58 }
  59
  60 Body::~Body() {
  61         for (creature::Creature *c : creatures) {
  62                 delete c;
  63         }
  64 }
  65
  66 void Body::SetSimulation(Simulation &s) noexcept {
  67         sim = &s;
  68         for (auto child : children) {
  69                 child->SetSimulation(s);
  70         }
  71 }
  72
  73 void Body::SetParent(Body &p) {
  74         if (HasParent()) {
  75                 UnsetParent();
  76         }
  77         parent = &p;
  78         parent->AddChild(*this);
  79 }
  80
  81 void Body::UnsetParent() {
  82         if (!HasParent()) return;
  83         parent->RemoveChild(*this);
  84         parent = nullptr;
  85 }
  86
  87 void Body::AddChild(Body &c) {
  88         children.push_back(&c);
  89         c.SetSimulation(*sim);
  90 }
  91
  92 void Body::RemoveChild(Body &c) {
  93         auto entry = std::find(children.begin(), children.end(), &c);
  94         if (entry != children.end()) {
  95                 children.erase(entry);
  96         }
  97 }
  98
  99 double Body::Inertia() const noexcept {
 100         // assume solid sphere for now
 101         return (2.0/5.0) * Mass() * pow(Radius(), 2);
 102 }
 103
 104 double Body::GravitationalParameter() const noexcept {
 105         return G * Mass();
 106 }
 107
 108 double Body::OrbitalPeriod() const noexcept {
 109         if (parent) {
 110                 return PI_2p0 * sqrt(pow(orbit.SemiMajorAxis(), 3) / (G * (parent->Mass() + Mass())));
 111         } else {
 112                 return 0.0;
 113         }
 114 }
 115
 116 double Body::RotationalPeriod() const noexcept {
 117         if (std::abs(angular) < std::numeric_limits<double>::epsilon()) {
 118                 return std::numeric_limits<double>::infinity();
 119         } else {
 120                 return PI_2p0 * Inertia() / angular;
 121         }
 122 }
 123
 124 glm::dmat4 Body::ToUniverse() const noexcept {
 125         glm::dmat4 m(1.0);
 126         const Body *b = this;
 127         while (b->HasParent()) {
 128                 m = b->ToParent() * m;
 129                 b = &b->Parent();
 130         }
 131         return m;
 132 }
 133
 134 glm::dmat4 Body::FromUniverse() const noexcept {
 135         glm::dmat4 m(1.0);
 136         const Body *b = this;
 137         while (b->HasParent()) {
 138                 m *= b->FromParent();
 139                 b = &b->Parent();
 140         }
 141         return m;
 142 }
 143
 144 namespace {
 145 std::vector<creature::Creature *> ccache;
 146 std::vector<CreatureCreatureCollision> collisions;
 147 }
 148
 149 void Body::Tick(double dt) {
 150         rotation += dt * AngularMomentum() / Inertia();
 151         Cache();
 152         ccache = Creatures();
 153         for (creature::Creature *c : ccache) {
 154                 c->Tick(dt);
 155         }
 156         // first remove creatures so they don't collide
 157         for (auto c = Creatures().begin(); c != Creatures().end();) {
 158                 if ((*c)->Removable()) {
 159                         delete *c;
 160                         c = Creatures().erase(c);
 161                 } else {
 162                         ++c;
 163                 }
 164         }
 165         CheckCollision();
 166 }
 167
 168 void Body::Cache() noexcept {
 169         if (parent) {
 170                 orbital =
 171                         orbit.Matrix(PI_2p0 * (GetSimulation().Time() / OrbitalPeriod()))
 172                         * glm::eulerAngleXY(axis_tilt.x, axis_tilt.y);
 173                 inverse_orbital =
 174                         glm::eulerAngleYX(-axis_tilt.y, -axis_tilt.x)
 175                         * orbit.InverseMatrix(PI_2p0 * (GetSimulation().Time() / OrbitalPeriod()));
 176         } else {
 177                 orbital = glm::eulerAngleXY(axis_tilt.x, axis_tilt.y);
 178                 inverse_orbital = glm::eulerAngleYX(-axis_tilt.y, -axis_tilt.x);
 179         }
 180         local =
 181                 glm::eulerAngleY(rotation)
 182                 * glm::eulerAngleXY(surface_tilt.x, surface_tilt.y);
 183         inverse_local =
 184                 glm::eulerAngleYX(-surface_tilt.y, -surface_tilt.x)
 185                 * glm::eulerAngleY(-rotation);
 186 }
 187
 188 void Body::CheckCollision() noexcept {
 189         if (Creatures().size() < 2) return;
 190         collisions.clear();
 191         auto end = Creatures().end();
 192         for (auto i = Creatures().begin(); i != end; ++i) {
 193                 math::AABB i_box((*i)->CollisionBox());
 194                 glm::dmat4 i_mat((*i)->CollisionTransform());
 195                 for (auto j = (i + 1); j != end; ++j) {
 196                         glm::dvec3 diff((*i)->GetSituation().Position() - (*j)->GetSituation().Position());
 197                         double max_dist = ((*i)->Size() + (*j)->Size()) * 1.74;
 198                         if (length2(diff) > max_dist * max_dist) continue;
 199                         math::AABB j_box((*j)->CollisionBox());
 200                         glm::dmat4 j_mat((*j)->CollisionTransform());
 201                         glm::dvec3 normal;
 202                         double depth;
 203                         if (Intersect(i_box, i_mat, j_box, j_mat, normal, depth)) {
 204                                 collisions.push_back({ **i, **j, normal, depth });
 205                         }
 206                 }
 207         }
 208         for (auto &c : collisions) {
 209                 c.A().GetSituation().Move(c.Normal() * (c.Depth() * -0.5));
 210                 c.B().GetSituation().Move(c.Normal() * (c.Depth() * 0.5));
 211                 c.A().GetSituation().Accelerate(c.Normal() * -dot(c.Normal(), c.AVel()));
 212                 c.B().GetSituation().Accelerate(c.Normal() * -dot(c.Normal(), c.BVel()));
 213                 // TODO: notify participants so they can be annoyed
 214         }
 215 }
 216
 217 void Body::AddCreature(creature::Creature *c) {
 218         creatures.push_back(c);
 219 }
 220
 221 void Body::RemoveCreature(creature::Creature *c) {
 222         auto entry = std::find(creatures.begin(), creatures.end(), c);
 223         if (entry != creatures.end()) {
 224                 creatures.erase(entry);
 225         }
 226 }
 227
 228
 229 CreatureCreatureCollision::~CreatureCreatureCollision() {
 230 }
 231
 232 const glm::dvec3 &CreatureCreatureCollision::APos() const noexcept {
 233         return a->GetSituation().Position();
 234 }
 235
 236 const glm::dvec3 &CreatureCreatureCollision::AVel() const noexcept {
 237         return a->GetSituation().Velocity();
 238 }
 239
 240 const glm::dvec3 &CreatureCreatureCollision::BPos() const noexcept {
 241         return b->GetSituation().Position();
 242 }
 243
 244 const glm::dvec3 &CreatureCreatureCollision::BVel() const noexcept {
 245         return b->GetSituation().Velocity();
 246 }
 247
 248
 249 Orbit::Orbit()
 250 : sma(1.0)
 251 , ecc(0.0)
 252 , inc(0.0)
 253 , asc(0.0)
 254 , arg(0.0)
 255 , mna(0.0) {
 256 }
 257
 258 Orbit::~Orbit() {
 259 }
 260
 261 double Orbit::SemiMajorAxis() const noexcept {
 262         return sma;
 263 }
 264
 265 Orbit &Orbit::SemiMajorAxis(double s) noexcept {
 266         sma = s;
 267         return *this;
 268 }
 269
 270 double Orbit::Eccentricity() const noexcept {
 271         return ecc;
 272 }
 273
 274 Orbit &Orbit::Eccentricity(double e) noexcept {
 275         ecc = e;
 276         return *this;
 277 }
 278
 279 double Orbit::Inclination() const noexcept {
 280         return inc;
 281 }
 282
 283 Orbit &Orbit::Inclination(double i) noexcept {
 284         inc = i;
 285         return *this;
 286 }
 287
 288 double Orbit::LongitudeAscending() const noexcept {
 289         return asc;
 290 }
 291
 292 Orbit &Orbit::LongitudeAscending(double l) noexcept {
 293         asc = l;
 294         return *this;
 295 }
 296
 297 double Orbit::ArgumentPeriapsis() const noexcept {
 298         return arg;
 299 }
 300
 301 Orbit &Orbit::ArgumentPeriapsis(double a) noexcept {
 302         arg = a;
 303         return *this;
 304 }
 305
 306 double Orbit::MeanAnomaly() const noexcept {
 307         return mna;
 308 }
 309
 310 Orbit &Orbit::MeanAnomaly(double m) noexcept {
 311         mna = m;
 312         return *this;
 313 }
 314
 315 namespace {
 316
 317 double mean2eccentric(double M, double e) {
 318         double E = M; // eccentric anomaly, solve M = E - e sin E
 319         // limit to 100 steps to prevent deadlocks in impossible situations
 320         for (int i = 0; i < 100; ++i) {
 321                 double dE = (E - e * sin(E) - M) / (1 - e * cos(E));
 322                 E -= dE;
 323                 if (abs(dE) < 1.0e-6) break;
 324         }
 325         return E;
 326 }
 327
 328 }
 329
 330 glm::dmat4 Orbit::Matrix(double t) const noexcept {
 331         double M = mna + t;
 332         double E = mean2eccentric(M, ecc);
 333
 334         // coordinates in orbital plane, P=x, Q=-z
 335         double P = sma * (cos(E) - ecc);
 336         double Q = sma * sin(E) * sqrt(1 - (ecc * ecc));
 337
 338         return glm::yawPitchRoll(asc, inc, arg) * glm::translate(glm::dvec3(P, 0.0, -Q));
 339 }
 340
 341 glm::dmat4 Orbit::InverseMatrix(double t) const noexcept {
 342         double M = mna + t;
 343         double E = mean2eccentric(M, ecc);
 344         double P = sma * (cos(E) - ecc);
 345         double Q = sma * sin(E) * sqrt(1 - (ecc * ecc));
 346         return glm::translate(glm::dvec3(-P, 0.0, Q)) * glm::transpose(glm::yawPitchRoll(asc, inc, arg));
 347 }
 348
 349
 350 Planet::Planet(int sidelength)
 351 : Body()
 352 , sidelength(sidelength)
 353 , tiles(TilesTotal())
 354 , vao() {
 355         Radius(double(sidelength) / 2.0);
 356 }
 357
 358 Planet::~Planet() {
 359 }
 360
 361 const TileType &Planet::TypeAt(int srf, int x, int y) const {
 362         return GetSimulation().TileTypes()[TileAt(srf, x, y).type];
 363 }
 364
 365 glm::ivec2 Planet::SurfacePosition(int srf, const glm::dvec3 &pos) const noexcept {
 366         return glm::ivec2(
 367                 PositionToTile(pos[(srf + 0) % 3]),
 368                 PositionToTile(pos[(srf + 1) % 3]));
 369 }
 370
 371 double Planet::SurfaceElevation(int srf, const glm::dvec3 &pos) const noexcept {
 372         return srf < 3
 373                 ? pos[(srf + 2) % 3] - Radius()
 374                 : -pos[(srf + 2) % 3] - Radius();
 375 }
 376
 377 glm::dvec3 Planet::TileCenter(int srf, int x, int y, double e) const noexcept {
 378         glm::dvec3 center(0.0f);
 379         center[(srf + 0) % 3] = x + 0.5 - Radius();
 380         center[(srf + 1) % 3] = y + 0.5 - Radius();
 381         center[(srf + 2) % 3] = srf < 3 ? (Radius() + e) : -(Radius() + e);
 382         return center;
 383 }
 384
 385 void Planet::BuildVAO(const Set<TileType> &ts) {
 386         vao.reset(new graphics::SimpleVAO<Attributes, unsigned int>);
 387         vao->Bind();
 388         vao->BindAttributes();
 389         vao->EnableAttribute(0);
 390         vao->EnableAttribute(1);
 391         vao->AttributePointer<glm::vec3>(0, false, offsetof(Attributes, position));
 392         vao->AttributePointer<glm::vec3>(1, false, offsetof(Attributes, tex_coord));
 393         vao->ReserveAttributes(TilesTotal() * 4, GL_STATIC_DRAW);
 394         {
 395                 auto attrib = vao->MapAttributes(GL_WRITE_ONLY);
 396                 float offset = Radius();
 397
 398                 // srf  0  1  2  3  4  5
 399                 //  up +Z +X +Y -Z -X -Y
 400
 401                 for (int index = 0, surface = 0; surface < 6; ++surface) {
 402                         for (int y = 0; y < sidelength; ++y) {
 403                                 for (int x = 0; x < sidelength; ++x, ++index) {
 404                                         float tex = ts[TileAt(surface, x, y).type].texture;
 405                                         const float tex_v_begin = surface < 3 ? 1.0f : 0.0f;
 406                                         const float tex_v_end = surface < 3 ? 0.0f : 1.0f;
 407                                         attrib[4 * index + 0].position[(surface + 0) % 3] = x + 0 - offset;
 408                                         attrib[4 * index + 0].position[(surface + 1) % 3] = y + 0 - offset;
 409                                         attrib[4 * index + 0].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 410                                         attrib[4 * index + 0].tex_coord[0] = 0.0f;
 411                                         attrib[4 * index + 0].tex_coord[1] = tex_v_begin;
 412                                         attrib[4 * index + 0].tex_coord[2] = tex;
 413
 414                                         attrib[4 * index + 1].position[(surface + 0) % 3] = x + 0 - offset;
 415                                         attrib[4 * index + 1].position[(surface + 1) % 3] = y + 1 - offset;
 416                                         attrib[4 * index + 1].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 417                                         attrib[4 * index + 1].tex_coord[0] = 0.0f;
 418                                         attrib[4 * index + 1].tex_coord[1] = tex_v_end;
 419                                         attrib[4 * index + 1].tex_coord[2] = tex;
 420
 421                                         attrib[4 * index + 2].position[(surface + 0) % 3] = x + 1 - offset;
 422                                         attrib[4 * index + 2].position[(surface + 1) % 3] = y + 0 - offset;
 423                                         attrib[4 * index + 2].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 424                                         attrib[4 * index + 2].tex_coord[0] = 1.0f;
 425                                         attrib[4 * index + 2].tex_coord[1] = tex_v_begin;
 426                                         attrib[4 * index + 2].tex_coord[2] = tex;
 427
 428                                         attrib[4 * index + 3].position[(surface + 0) % 3] = x + 1 - offset;
 429                                         attrib[4 * index + 3].position[(surface + 1) % 3] = y + 1 - offset;
 430                                         attrib[4 * index + 3].position[(surface + 2) % 3] = surface < 3 ? offset : -offset;
 431                                         attrib[4 * index + 3].tex_coord[0] = 1.0f;
 432                                         attrib[4 * index + 3].tex_coord[1] = tex_v_end;
 433                                         attrib[4 * index + 3].tex_coord[2] = tex;
 434                                 }
 435                         }
 436                 }
 437         }
 438         vao->BindElements();
 439         vao->ReserveElements(TilesTotal() * 6, GL_STATIC_DRAW);
 440         {
 441                 auto element = vao->MapElements(GL_WRITE_ONLY);
 442                 int index = 0;
 443                 for (int surface = 0; surface < 3; ++surface) {
 444                         for (int y = 0; y < sidelength; ++y) {
 445                                 for (int x = 0; x < sidelength; ++x, ++index) {
 446                                         element[6 * index + 0] = 4 * index + 0;
 447                                         element[6 * index + 1] = 4 * index + 2;
 448                                         element[6 * index + 2] = 4 * index + 1;
 449                                         element[6 * index + 3] = 4 * index + 1;
 450                                         element[6 * index + 4] = 4 * index + 2;
 451                                         element[6 * index + 5] = 4 * index + 3;
 452                                 }
 453                         }
 454                 }
 455                 for (int surface = 3; surface < 6; ++surface) {
 456                         for (int y = 0; y < sidelength; ++y) {
 457                                 for (int x = 0; x < sidelength; ++x, ++index) {
 458                                         element[6 * index + 0] = 4 * index + 0;
 459                                         element[6 * index + 1] = 4 * index + 1;
 460                                         element[6 * index + 2] = 4 * index + 2;
 461                                         element[6 * index + 3] = 4 * index + 2;
 462                                         element[6 * index + 4] = 4 * index + 1;
 463                                         element[6 * index + 5] = 4 * index + 3;
 464                                 }
 465                         }
 466                 }
 467         }
 468         vao->Unbind();
 469 }
 470
 471 void Planet::Draw(app::Assets &assets, graphics::Viewport &viewport) {
 472         if (!vao) return;
 473
 474         vao->Bind();
 475         const glm::mat4 &MV = assets.shaders.planet_surface.MV();
 476         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(0.0f, 0.0f, 1.0f, 0.0f)));
 477         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 0);
 478         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(1.0f, 0.0f, 0.0f, 0.0f)));
 479         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 1);
 480         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(0.0f, 1.0f, 0.0f, 0.0f)));
 481         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 2);
 482         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(0.0f, 0.0f, -1.0f, 0.0f)));
 483         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 3);
 484         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(-1.0f, 0.0f, 0.0f, 0.0f)));
 485         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 4);
 486         assets.shaders.planet_surface.SetNormal(glm::vec3(MV * glm::vec4(0.0f, -1.0f, 0.0f, 0.0f)));
 487         vao->DrawTriangles(TilesPerSurface() * 6, TilesPerSurface() * 6 * 5);
 488 }
 489
 490
 491 void GenerateEarthlike(const Set<TileType> &tiles, Planet &p) noexcept {
 492         math::SimplexNoise elevation_gen(0);
 493         math::SimplexNoise variation_gen(45623752346);
 494
 495         const int ice = tiles["ice"].id;
 496         const int ocean = tiles["ocean"].id;
 497         const int water = tiles["water"].id;
 498         const int sand = tiles["sand"].id;
 499         const int grass = tiles["grass"].id;
 500         const int tundra = tiles["tundra"].id;
 501         const int taiga = tiles["taiga"].id;
 502         const int desert = tiles["desert"].id;
 503         const int mntn = tiles["mountain"].id;
 504         const int algae = tiles["algae"].id;
 505         const int forest = tiles["forest"].id;
 506         const int jungle = tiles["jungle"].id;
 507         const int rock = tiles["rock"].id;
 508         const int wheat = tiles["wheat"].id;
 509
 510         constexpr double ocean_thresh = -0.2;
 511         constexpr double water_thresh = 0.0;
 512         constexpr double beach_thresh = 0.05;
 513         constexpr double highland_thresh = 0.4;
 514         constexpr double mountain_thresh = 0.5;
 515
 516         const glm::dvec3 axis(glm::dvec4(0.0, 1.0, 0.0, 0.0) * glm::eulerAngleXY(p.SurfaceTilt().x, p.SurfaceTilt().y));
 517         const double cap_thresh = std::abs(std::cos(p.AxialTilt().x));
 518         const double equ_thresh = std::abs(std::sin(p.AxialTilt().x)) / 2.0;
 519         const double fzone_start = equ_thresh - (equ_thresh - cap_thresh) / 3.0;
 520         const double fzone_end = cap_thresh + (equ_thresh - cap_thresh) / 3.0;
 521
 522         for (int surface = 0; surface <= 5; ++surface) {
 523                 for (int y = 0; y < p.SideLength(); ++y) {
 524                         for (int x = 0; x < p.SideLength(); ++x) {
 525                                 glm::dvec3 to_tile = p.TileCenter(surface, x, y);
 526                                 double near_axis = std::abs(glm::dot(glm::normalize(to_tile), axis));
 527                                 if (near_axis > cap_thresh) {
 528                                         p.TileAt(surface, x, y).type = ice;
 529                                         continue;
 530                                 }
 531                                 float elevation = math::OctaveNoise(
 532                                         elevation_gen,
 533                                         to_tile / p.Radius(),
 534                                         3,   // octaves
 535                                         0.5, // persistence
 536                                         5 / p.Radius(), // frequency
 537                                         2,   // amplitude
 538                                         2    // growth
 539                                 );
 540                                 float variation = math::OctaveNoise(
 541                                         variation_gen,
 542                                         to_tile / p.Radius(),
 543                                         3,   // octaves
 544                                         0.5, // persistence
 545                                         16 / p.Radius(), // frequency
 546                                         2,   // amplitude
 547                                         2    // growth
 548                                 );
 549                                 if (elevation < ocean_thresh) {
 550                                         p.TileAt(surface, x, y).type = ocean;
 551                                 } else if (elevation < water_thresh) {
 552                                         if (variation > 0.3) {
 553                                                 p.TileAt(surface, x, y).type = algae;
 554                                         } else {
 555                                                 p.TileAt(surface, x, y).type = water;
 556                                         }
 557                                 } else if (elevation < beach_thresh) {
 558                                         p.TileAt(surface, x, y).type = sand;
 559                                 } else if (elevation < highland_thresh) {
 560                                         if (near_axis < equ_thresh) {
 561                                                 if (variation > 0.6) {
 562                                                         p.TileAt(surface, x, y).type = grass;
 563                                                 } else if (variation > 0.2) {
 564                                                         p.TileAt(surface, x, y).type = sand;
 565                                                 } else {
 566                                                         p.TileAt(surface, x, y).type = desert;
 567                                                 }
 568                                         } else if (near_axis < fzone_start) {
 569                                                 if (variation > 0.4) {
 570                                                         p.TileAt(surface, x, y).type = forest;
 571                                                 } else if (variation < -0.5) {
 572                                                         p.TileAt(surface, x, y).type = jungle;
 573                                                 } else if (variation > -0.02 && variation < 0.02) {
 574                                                         p.TileAt(surface, x, y).type = wheat;
 575                                                 } else {
 576                                                         p.TileAt(surface, x, y).type = grass;
 577                                                 }
 578                                         } else if (near_axis < fzone_end) {
 579                                                 p.TileAt(surface, x, y).type = tundra;
 580                                         } else {
 581                                                 p.TileAt(surface, x, y).type = taiga;
 582                                         }
 583                                 } else if (elevation < mountain_thresh) {
 584                                         if (variation > 0.3) {
 585                                                 p.TileAt(surface, x, y).type = mntn;
 586                                         } else {
 587                                                 p.TileAt(surface, x, y).type = rock;
 588                                         }
 589                                 } else {
 590                                         p.TileAt(surface, x, y).type = mntn;
 591                                 }
 592                         }
 593                 }
 594         }
 595         p.BuildVAO(tiles);
 596 }
 597
 598 void GenerateTest(const Set<TileType> &tiles, Planet &p) noexcept {
 599         for (int surface = 0; surface <= 5; ++surface) {
 600                 for (int y = 0; y < p.SideLength(); ++y) {
 601                         for (int x = 0; x < p.SideLength(); ++x) {
 602                                 if (x == p.SideLength() / 2 && y == p.SideLength() / 2) {
 603                                         p.TileAt(surface, x, y).type = surface;
 604                                 } else {
 605                                         p.TileAt(surface, x, y).type = (x == p.SideLength()/2) + (y == p.SideLength()/2) + 6;
 606                                 }
 607                         }
 608                 }
 609         }
 610         p.BuildVAO(tiles);
 611 }
 612
 613
 614 Sun::Sun()
 615 : Body() {
 616 }
 617
 618 Sun::~Sun() {
 619 }
 620
 621
 622 std::vector<TileType::Yield>::const_iterator TileType::FindResource(int r) const {
 623         auto yield = resources.cbegin();
 624         for (; yield != resources.cend(); ++yield) {
 625                 if (yield->resource == r) {
 626                         break;
 627                 }
 628         }
 629         return yield;
 630 }
 631
 632 std::vector<TileType::Yield>::const_iterator TileType::FindBestResource(const creature::Composition &comp) const {
 633         auto best = resources.cend();
 634         double best_value = 0.0;
 635         for (auto yield = resources.cbegin(); yield != resources.cend(); ++yield) {
 636                 double value = comp.Get(yield->resource);
 637                 if (value > best_value) {
 638                         best = yield;
 639                         best_value = value;
 640                 }
 641         }
 642         return best;
 643 }
 644
 645 }
 646 }