src/world/chunk.cpp

   1 #include "BlockLookup.hpp"
   2 #include "Chunk.hpp"
   3 #include "ChunkIndex.hpp"
   4 #include "ChunkLoader.hpp"
   5 #include "ChunkRenderer.hpp"
   6 #include "ChunkStore.hpp"
   7
   8 #include "Generator.hpp"
   9 #include "WorldCollision.hpp"
  10 #include "../app/Assets.hpp"
  11 #include "../geometry/distance.hpp"
  12 #include "../graphics/BlockLighting.hpp"
  13 #include "../graphics/BlockMesh.hpp"
  14 #include "../graphics/Viewport.hpp"
  15 #include "../io/WorldSave.hpp"
  16
  17 #include <algorithm>
  18 #include <limits>
  19 #include <ostream>
  20 #include <queue>
  21
  22
  23 namespace blank {
  24
  25 constexpr int Chunk::side;
  26 constexpr int Chunk::size;
  27
  28
  29 Chunk::Chunk(const BlockTypeRegistry &types) noexcept
  30 : types(&types)
  31 , neighbor{0}
  32 , blocks{}
  33 , light{0}
  34 , generated(false)
  35 , lighted(false)
  36 , position(0, 0, 0)
  37 , ref_count(0)
  38 , dirty_mesh(false)
  39 , dirty_save(false) {
  40
  41 }
  42
  43 Chunk::Chunk(Chunk &&other) noexcept
  44 : types(other.types)
  45 , generated(other.generated)
  46 , lighted(other.lighted)
  47 , position(other.position)
  48 , ref_count(other.ref_count)
  49 , dirty_mesh(other.dirty_mesh)
  50 , dirty_save(other.dirty_save) {
  51         std::copy(other.neighbor, other.neighbor + sizeof(neighbor), neighbor);
  52         std::copy(other.blocks, other.blocks + sizeof(blocks), blocks);
  53         std::copy(other.light, other.light + sizeof(light), light);
  54         other.ref_count = 0;
  55 }
  56
  57 Chunk &Chunk::operator =(Chunk &&other) noexcept {
  58         types = other.types;
  59         std::copy(other.neighbor, other.neighbor + sizeof(neighbor), neighbor);
  60         std::copy(other.blocks, other.blocks + sizeof(blocks), blocks);
  61         std::copy(other.light, other.light + sizeof(light), light);
  62         generated = other.generated;
  63         lighted = other.lighted;
  64         position = other.position;
  65         std::swap(ref_count, other.ref_count);
  66         dirty_mesh = other.dirty_save;
  67         dirty_save = other.dirty_save;
  68         return *this;
  69 }
  70
  71
  72 namespace {
  73
  74 struct SetNode {
  75
  76         Chunk *chunk;
  77         RoughLocation::Fine pos;
  78
  79         SetNode(Chunk *chunk, RoughLocation::Fine pos)
  80         : chunk(chunk), pos(pos) { }
  81
  82         int Get() const noexcept { return chunk->GetLight(pos); }
  83         void Set(int level) noexcept { chunk->SetLight(pos, level); }
  84
  85         const BlockType &GetType() const noexcept { return chunk->Type(Chunk::ToIndex(pos)); }
  86
  87         bool HasNext(Block::Face face) noexcept {
  88                 const BlockType &type = GetType();
  89                 if (type.block_light && !type.luminosity) return false;
  90                 const BlockLookup next(chunk, pos, face);
  91                 return next;
  92         }
  93         SetNode GetNext(Block::Face face) noexcept {
  94                 const BlockLookup next(chunk, pos, face);
  95                 return SetNode(&next.GetChunk(), next.GetBlockPos());
  96         }
  97
  98 };
  99
 100 struct UnsetNode
 101 : public SetNode {
 102
 103         int level;
 104
 105         UnsetNode(Chunk *chunk, RoughLocation::Fine pos)
 106         : SetNode(chunk, pos), level(Get()) { }
 107
 108         UnsetNode(const SetNode &set)
 109         : SetNode(set), level(Get()) { }
 110
 111
 112         bool HasNext(Block::Face face) noexcept {
 113                 const BlockLookup next(chunk, pos, face);
 114                 return next;
 115         }
 116         UnsetNode GetNext(Block::Face face) noexcept { return UnsetNode(SetNode::GetNext(face)); }
 117
 118 };
 119
 120 std::queue<SetNode> light_queue;
 121 std::queue<UnsetNode> dark_queue;
 122
 123 void work_light() noexcept {
 124         while (!light_queue.empty()) {
 125                 SetNode node = light_queue.front();
 126                 light_queue.pop();
 127
 128                 int level = node.Get() - 1;
 129                 for (int face = 0; face < Block::FACE_COUNT; ++face) {
 130                         if (node.HasNext(Block::Face(face))) {
 131                                 SetNode other = node.GetNext(Block::Face(face));
 132                                 if (other.Get() < level) {
 133                                         other.Set(level);
 134                                         light_queue.emplace(other);
 135                                 }
 136                         }
 137                 }
 138         }
 139 }
 140
 141 void work_dark() noexcept {
 142         while (!dark_queue.empty()) {
 143                 UnsetNode node = dark_queue.front();
 144                 dark_queue.pop();
 145
 146                 for (int face = 0; face < Block::FACE_COUNT; ++face) {
 147                         if (node.HasNext(Block::Face(face))) {
 148                                 UnsetNode other = node.GetNext(Block::Face(face));
 149                                 // TODO: if there a light source here with the same level this will err
 150                                 if (other.Get() != 0 && other.Get() < node.level) {
 151                                         other.Set(0);
 152                                         dark_queue.emplace(other);
 153                                 } else {
 154                                         light_queue.emplace(other);
 155                                 }
 156                         }
 157                 }
 158         }
 159 }
 160
 161 }
 162
 163 void Chunk::SetBlock(int index, const Block &block) noexcept {
 164         const BlockType &old_type = Type(blocks[index]);
 165         const BlockType &new_type = Type(block);
 166
 167         blocks[index] = block;
 168         Invalidate();
 169
 170         if (!lighted || &old_type == &new_type) return;
 171
 172         if (new_type.luminosity > old_type.luminosity) {
 173                 // light added
 174                 SetLight(index, new_type.luminosity);
 175                 light_queue.emplace(this, ToPos(index));
 176                 work_light();
 177         } else if (new_type.luminosity < old_type.luminosity) {
 178                 // light removed
 179                 dark_queue.emplace(this, ToPos(index));
 180                 SetLight(index, 0);
 181                 work_dark();
 182                 SetLight(index, new_type.luminosity);
 183                 light_queue.emplace(this, ToPos(index));
 184                 work_light();
 185         } else if (new_type.block_light && !old_type.block_light) {
 186                 // obstacle added
 187                 if (GetLight(index) > 0) {
 188                         dark_queue.emplace(this, ToPos(index));
 189                         SetLight(index, 0);
 190                         work_dark();
 191                         work_light();
 192                 }
 193         } else if (!new_type.block_light && old_type.block_light) {
 194                 // obstacle removed
 195                 int level = 0;
 196                 RoughLocation::Fine pos(ToPos(index));
 197                 for (int face = 0; face < Block::FACE_COUNT; ++face) {
 198                         BlockLookup next_block(this, pos, Block::Face(face));
 199                         if (next_block) {
 200                                 level = std::max(level, next_block.GetLight());
 201                         }
 202                 }
 203                 if (level > 1) {
 204                         SetLight(index, level - 1);
 205                         light_queue.emplace(this, pos);
 206                         work_light();
 207                 }
 208         }
 209 }
 210
 211 void Chunk::ScanLights() {
 212         int idx = 0;
 213         RoughLocation::Fine pos(0, 0, 0);
 214         for (; pos.z < side; ++pos.z) {
 215                 for (pos.y = 0; pos.y < side; ++pos.y) {
 216                         for (pos.x = 0; pos.x < side; ++pos.x, ++idx) {
 217                                 const BlockType &type = Type(blocks[idx]);
 218                                 if (type.luminosity) {
 219                                         SetLight(idx, type.luminosity);
 220                                         light_queue.emplace(this, pos);
 221                                 }
 222                         }
 223                 }
 224         }
 225         work_light();
 226         lighted = true;
 227 }
 228
 229 void Chunk::SetNeighbor(Block::Face face, Chunk &other) noexcept {
 230         neighbor[face] = &other;
 231         other.neighbor[Block::Opposite(face)] = this;
 232 }
 233
 234 void Chunk::Unlink() noexcept {
 235         for (int face = 0; face < Block::FACE_COUNT; ++face) {
 236                 if (neighbor[face]) {
 237                         neighbor[face]->neighbor[Block::Opposite(Block::Face(face))] = nullptr;
 238                         neighbor[face] = nullptr;
 239                 }
 240         }
 241 }
 242
 243
 244 void Chunk::SetLight(int index, int level) noexcept {
 245         if (light[index] != level) {
 246                 light[index] = level;
 247                 Invalidate();
 248         }
 249 }
 250
 251 int Chunk::GetLight(int index) const noexcept {
 252         return light[index];
 253 }
 254
 255 float Chunk::GetVertexLight(const RoughLocation::Fine &pos, const BlockMesh::Position &vtx, const EntityMesh::Normal &norm) const noexcept {
 256         int index = ToIndex(pos);
 257         float light = GetLight(index);
 258
 259         Block::Face direct_face(Block::NormalFace(norm));
 260         // tis okay
 261         BlockLookup direct(const_cast<Chunk *>(this), pos, Block::NormalFace(norm));
 262         if (direct) {
 263                 float direct_light = direct.GetLight();
 264                 if (direct_light > light) {
 265                         light = direct_light;
 266                 }
 267         } else {
 268                 return light;
 269         }
 270
 271         if (Type(BlockAt(index)).luminosity > 0 || direct.GetType().block_light) {
 272                 return light;
 273         }
 274
 275         Block::Face edge[2];
 276         switch (Block::Axis(direct_face)) {
 277                 case 0: // X
 278                         edge[0] = (vtx.y - pos.y) > 0.5f ? Block::FACE_UP : Block::FACE_DOWN;
 279                         edge[1] = (vtx.z - pos.z) > 0.5f ? Block::FACE_FRONT : Block::FACE_BACK;
 280                         break;
 281                 case 1: // Y
 282                         edge[0] = (vtx.z - pos.z) > 0.5f ? Block::FACE_FRONT : Block::FACE_BACK;
 283                         edge[1] = (vtx.x - pos.x) > 0.5f ? Block::FACE_RIGHT : Block::FACE_LEFT;
 284                         break;
 285                 case 2: // Z
 286                         edge[0] = (vtx.x - pos.x) > 0.5f ? Block::FACE_RIGHT : Block::FACE_LEFT;
 287                         edge[1] = (vtx.y - pos.y) > 0.5f ? Block::FACE_UP : Block::FACE_DOWN;
 288                         break;
 289         }
 290
 291         int num = 1;
 292         int occlusion = 0;
 293
 294         BlockLookup next[2] = {
 295                 direct.Next(edge[0]),
 296                 direct.Next(edge[1]),
 297         };
 298
 299         if (next[0]) {
 300                 if (next[0].GetType().block_light) {
 301                         ++occlusion;
 302                 } else {
 303                         light += next[0].GetLight();
 304                         ++num;
 305                 }
 306         }
 307         if (next[1]) {
 308                 if (next[1].GetType().block_light) {
 309                         ++occlusion;
 310                 } else {
 311                         light += next[1].GetLight();
 312                         ++num;
 313                 }
 314         }
 315         if (occlusion < 2) {
 316                 if (next[0]) {
 317                         BlockLookup corner = next[0].Next(edge[1]);
 318                         if (corner) {
 319                                 if (corner.GetType().block_light) {
 320                                         ++occlusion;
 321                                 } else {
 322                                         light += corner.GetLight();
 323                                         ++num;
 324                                 }
 325                         }
 326                 } else if (next[1]) {
 327                         BlockLookup corner = next[1].Next(edge[0]);
 328                         if (corner) {
 329                                 if (corner.GetType().block_light) {
 330                                         ++occlusion;
 331                                 } else {
 332                                         light += corner.GetLight();
 333                                         ++num;
 334                                 }
 335                         }
 336                 }
 337         } else {
 338                 ++occlusion;
 339         }
 340
 341         return (light / num) - (occlusion * 0.8f);
 342 }
 343
 344
 345 bool Chunk::IsSurface(const RoughLocation::Fine &pos) const noexcept {
 346         const Block &block = BlockAt(pos);
 347         if (!Type(block).visible) {
 348                 return false;
 349         }
 350         for (int face = 0; face < Block::FACE_COUNT; ++face) {
 351                 BlockLookup next = BlockLookup(const_cast<Chunk *>(this), pos, Block::Face(face));
 352                 if (!next || !next.GetType().visible) {
 353                         return true;
 354                 }
 355         }
 356         return false;
 357 }
 358
 359
 360 bool Chunk::Intersection(
 361         const Ray &ray,
 362         const glm::mat4 &M,
 363         WorldCollision &coll
 364 ) noexcept {
 365         int idx = 0;
 366         coll.chunk = this;
 367         coll.block = -1;
 368         coll.depth = std::numeric_limits<float>::infinity();
 369         for (int z = 0; z < side; ++z) {
 370                 for (int y = 0; y < side; ++y) {
 371                         for (int x = 0; x < side; ++x, ++idx) {
 372                                 const BlockType &type = Type(idx);
 373                                 if (!type.collision || !type.shape) {
 374                                         continue;
 375                                 }
 376                                 float cur_dist;
 377                                 glm::vec3 cur_norm;
 378                                 if (type.shape->Intersects(ray, M * ToTransform(RoughLocation::Fine(x, y, z), idx), cur_dist, cur_norm)) {
 379                                         if (cur_dist < coll.depth) {
 380                                                 coll.block = idx;
 381                                                 coll.depth = cur_dist;
 382                                                 coll.normal = cur_norm;
 383                                         }
 384                                 }
 385                         }
 386                 }
 387         }
 388
 389         if (coll.block < 0) {
 390                 return false;
 391         } else {
 392                 coll.normal = glm::vec3(BlockAt(coll.block).Transform() * glm::vec4(coll.normal, 0.0f));
 393                 return true;
 394         }
 395 }
 396
 397 bool Chunk::Intersection(
 398         const AABB &box,
 399         const glm::mat4 &Mbox,
 400         const glm::mat4 &Mchunk,
 401         std::vector<WorldCollision> &col
 402 ) noexcept {
 403         // box's origin relative to the chunk
 404         const glm::vec3 box_coords(Mbox[3] - Mchunk[3]);
 405         const float box_rad = box.OriginRadius();
 406
 407         if (distance_squared(box_coords, Center()) > (box_rad + Radius()) * (box_rad + Radius())) {
 408                 return false;
 409         }
 410
 411         bool any = false;
 412         float penetration;
 413         glm::vec3 normal;
 414
 415         // assume a bounding radius of 2 for blocks
 416         constexpr float block_rad = 2.0f;
 417         for (int idx = 0, z = 0; z < side; ++z) {
 418                 for (int y = 0; y < side; ++y) {
 419                         for (int x = 0; x < side; ++x, ++idx) {
 420                                 const BlockType &type = Type(idx);
 421                                 if (!type.collision || !type.shape) {
 422                                         continue;
 423                                 }
 424                                 const RoughLocation::Fine block_pos(x, y, z);
 425                                 const ExactLocation::Fine block_coords(ToCoords(block_pos));
 426                                 if (distance_squared(box_coords, block_coords) <= (box_rad + block_rad) * (box_rad + block_rad)
 427                                         && type.shape->Intersects(Mchunk * ToTransform(block_pos, idx), box, Mbox, penetration, normal)
 428                                 ) {
 429                                         col.emplace_back(this, idx, penetration, normal);
 430                                         any = true;
 431                                 }
 432                         }
 433                 }
 434         }
 435         return any;
 436 }
 437
 438
 439 namespace {
 440
 441 BlockMesh::Buffer buf;
 442
 443 }
 444
 445 void Chunk::Update(BlockMesh &model) noexcept {
 446         int vtx_count = 0, idx_count = 0;
 447         for (const auto &block : blocks) {
 448                 const BlockType &type = Type(block);
 449                 if (type.visible && type.shape) {
 450                         vtx_count += type.shape->VertexCount();
 451                         idx_count += type.shape->IndexCount();
 452                 }
 453         }
 454         buf.Clear();
 455         buf.Reserve(vtx_count, idx_count);
 456
 457         if (idx_count > 0) {
 458                 int idx = 0;
 459                 BlockMesh::Index vtx_counter = 0;
 460                 for (size_t z = 0; z < side; ++z) {
 461                         for (size_t y = 0; y < side; ++y) {
 462                                 for (size_t x = 0; x < side; ++x, ++idx) {
 463                                         const BlockType &type = Type(BlockAt(idx));
 464                                         const RoughLocation::Fine pos(x, y, z);
 465
 466                                         if (!type.visible || !type.shape || Obstructed(pos).All()) continue;
 467
 468                                         type.FillBlockMesh(buf, ToTransform(pos, idx), vtx_counter);
 469                                         size_t vtx_begin = vtx_counter;
 470                                         vtx_counter += type.shape->VertexCount();
 471
 472                                         for (size_t vtx = vtx_begin; vtx < vtx_counter; ++vtx) {
 473                                                 buf.lights.emplace_back(GetVertexLight(
 474                                                         pos,
 475                                                         buf.vertices[vtx],
 476                                                         type.shape->VertexNormal(vtx - vtx_begin, BlockAt(idx).Transform())
 477                                                 ));
 478                                         }
 479                                 }
 480                         }
 481                 }
 482         }
 483
 484         model.Update(buf);
 485         ClearMesh();
 486 }
 487
 488 Block::FaceSet Chunk::Obstructed(const RoughLocation::Fine &pos) const noexcept {
 489         Block::FaceSet result;
 490
 491         for (int f = 0; f < Block::FACE_COUNT; ++f) {
 492                 Block::Face face = Block::Face(f);
 493                 BlockLookup next(const_cast<Chunk *>(this), pos, face);
 494                 if (next && next.GetType().FaceFilled(next.GetBlock(), Block::Opposite(face))) {
 495                         result.Set(face);
 496                 }
 497         }
 498
 499         return result;
 500 }
 501
 502 glm::mat4 Chunk::ToTransform(const RoughLocation::Fine &pos, int idx) const noexcept {
 503         return glm::translate(ToCoords(pos)) * BlockAt(idx).Transform();
 504 }
 505
 506
 507 BlockLookup::BlockLookup(Chunk *c, const RoughLocation::Fine &p) noexcept
 508 : chunk(c), pos(p) {
 509         while (pos.x >= Chunk::side) {
 510                 if (chunk->HasNeighbor(Block::FACE_RIGHT)) {
 511                         chunk = &chunk->GetNeighbor(Block::FACE_RIGHT);
 512                         pos.x -= Chunk::side;
 513                 } else {
 514                         chunk = nullptr;
 515                         return;
 516                 }
 517         }
 518         while (pos.x < 0) {
 519                 if (chunk->HasNeighbor(Block::FACE_LEFT)) {
 520                         chunk = &chunk->GetNeighbor(Block::FACE_LEFT);
 521                         pos.x += Chunk::side;
 522                 } else {
 523                         chunk = nullptr;
 524                         return;
 525                 }
 526         }
 527         while (pos.y >= Chunk::side) {
 528                 if (chunk->HasNeighbor(Block::FACE_UP)) {
 529                         chunk = &chunk->GetNeighbor(Block::FACE_UP);
 530                         pos.y -= Chunk::side;
 531                 } else {
 532                         chunk = nullptr;
 533                         return;
 534                 }
 535         }
 536         while (pos.y < 0) {
 537                 if (chunk->HasNeighbor(Block::FACE_DOWN)) {
 538                         chunk = &chunk->GetNeighbor(Block::FACE_DOWN);
 539                         pos.y += Chunk::side;
 540                 } else {
 541                         chunk = nullptr;
 542                         return;
 543                 }
 544         }
 545         while (pos.z >= Chunk::side) {
 546                 if (chunk->HasNeighbor(Block::FACE_FRONT)) {
 547                         chunk = &chunk->GetNeighbor(Block::FACE_FRONT);
 548                         pos.z -= Chunk::side;
 549                 } else {
 550                         chunk = nullptr;
 551                         return;
 552                 }
 553         }
 554         while (pos.z < 0) {
 555                 if (chunk->HasNeighbor(Block::FACE_BACK)) {
 556                         chunk = &chunk->GetNeighbor(Block::FACE_BACK);
 557                         pos.z += Chunk::side;
 558                 } else {
 559                         chunk = nullptr;
 560                         return;
 561                 }
 562         }
 563 }
 564
 565 BlockLookup::BlockLookup(Chunk *c, const RoughLocation::Fine &p, Block::Face face) noexcept
 566 : chunk(c), pos(p) {
 567         pos += Block::FaceNormal(face);
 568         if (!Chunk::InBounds(pos)) {
 569                 pos -= Block::FaceNormal(face) * ExactLocation::Extent();
 570                 chunk = &chunk->GetNeighbor(face);
 571         }
 572 }
 573
 574
 575 ChunkLoader::ChunkLoader(
 576         ChunkStore &store,
 577         const Generator &gen,
 578         const WorldSave &save
 579 ) noexcept
 580 : store(store)
 581 , gen(gen)
 582 , save(save) {
 583
 584 }
 585
 586 void ChunkLoader::Update(int dt) {
 587         // check if there's chunks waiting to be loaded
 588         // load until one of load or generation limits was hit
 589         constexpr int max_load = 10;
 590         constexpr int max_gen = 1;
 591         int loaded = 0;
 592         int generated = 0;
 593         while (loaded < max_load && generated < max_gen && store.HasMissing()) {
 594                 if (LoadOne()) {
 595                         ++generated;
 596                 } else {
 597                         ++loaded;
 598                 }
 599         }
 600
 601         // store a few chunks as well
 602         constexpr int max_save = 10;
 603         int saved = 0;
 604         for (Chunk &chunk : store) {
 605                 if (chunk.ShouldUpdateSave()) {
 606                         save.Write(chunk);
 607                         ++saved;
 608                         if (saved >= max_save) {
 609                                 break;
 610                         }
 611                 }
 612         }
 613 }
 614
 615 int ChunkLoader::ToLoad() const noexcept {
 616         return store.EstimateMissing();
 617 }
 618
 619 bool ChunkLoader::LoadOne() {
 620         if (!store.HasMissing()) return false;
 621
 622         ExactLocation::Coarse pos = store.NextMissing();
 623         Chunk *chunk = store.Allocate(pos);
 624         if (!chunk) {
 625                 // chunk store corrupted?
 626                 return false;
 627         }
 628
 629         bool generated = false;
 630         if (save.Exists(pos)) {
 631                 save.Read(*chunk);
 632         } else {
 633                 gen(*chunk);
 634                 generated = true;
 635         }
 636
 637         ChunkIndex *index = store.ClosestIndex(pos);
 638         if (!index) {
 639                 return generated;
 640         }
 641
 642         ExactLocation::Coarse begin(pos - ExactLocation::Coarse(1));
 643         ExactLocation::Coarse end(pos + ExactLocation::Coarse(2));
 644         for (ExactLocation::Coarse iter(begin); iter.z < end.z; ++iter.z) {
 645                 for (iter.y = begin.y; iter.y < end.y; ++iter.y) {
 646                         for (iter.x = begin.x; iter.x < end.x; ++iter.x) {
 647                                 if (index->IsBorder(iter)) continue;
 648                                 Chunk *light_chunk = index->Get(iter);
 649                                 if (!light_chunk) continue;
 650                                 if (index->HasAllSurrounding(iter)) {
 651                                         if (!light_chunk->Lighted()) {
 652                                                 light_chunk->ScanLights();
 653                                         } else {
 654                                                 light_chunk->InvalidateMesh();
 655                                         }
 656                                 }
 657                         }
 658                 }
 659         }
 660
 661         return generated;
 662 }
 663
 664 void ChunkLoader::LoadN(std::size_t n) {
 665         std::size_t end = std::min(n, std::size_t(ToLoad()));
 666         for (std::size_t i = 0; i < end && store.HasMissing(); ++i) {
 667                 LoadOne();
 668         }
 669 }
 670
 671
 672 ChunkRenderer::ChunkRenderer(ChunkIndex &index)
 673 : index(index)
 674 , models(index.TotalChunks())
 675 , block_tex()
 676 , fog_density(0.0f) {
 677
 678 }
 679
 680 ChunkRenderer::~ChunkRenderer() {
 681
 682 }
 683
 684 int ChunkRenderer::MissingChunks() const noexcept {
 685         return index.MissingChunks();
 686 }
 687
 688 void ChunkRenderer::LoadTextures(const AssetLoader &loader, const ResourceIndex &tex_index) {
 689         block_tex.Bind();
 690         loader.LoadTextures(tex_index, block_tex);
 691         block_tex.FilterNearest();
 692 }
 693
 694 void ChunkRenderer::Update(int dt) {
 695         for (int i = 0, updates = 0; updates < dt && i < index.TotalChunks(); ++i) {
 696                 if (!index[i]) continue;
 697                 if (!index[i]->Lighted() && index.HasAllSurrounding(index[i]->Position())) {
 698                         index[i]->ScanLights();
 699                 }
 700                 if (index[i]->ShouldUpdateMesh()) {
 701                         index[i]->Update(models[i]);
 702                         ++updates;
 703                 }
 704         }
 705 }
 706
 707 void ChunkRenderer::Render(Viewport &viewport) {
 708         BlockLighting &chunk_prog = viewport.ChunkProgram();
 709         chunk_prog.SetTexture(block_tex);
 710         chunk_prog.SetFogDensity(fog_density);
 711
 712         for (int i = 0; i < index.TotalChunks(); ++i) {
 713                 if (!index[i]) continue;
 714                 glm::mat4 m(index[i]->Transform(index.Base()));
 715                 glm::mat4 mvp(chunk_prog.GetVP() * m);
 716                 if (!CullTest(Chunk::Bounds(), mvp)) {
 717                         if (index[i]->ShouldUpdateMesh()) {
 718                                 index[i]->Update(models[i]);
 719                         }
 720                         chunk_prog.SetM(m);
 721                         models[i].Draw();
 722                 }
 723         }
 724 }
 725
 726
 727 ChunkIndex::ChunkIndex(ChunkStore &store, const ExactLocation::Coarse &base, int extent)
 728 : store(store)
 729 , base(base)
 730 , extent(extent)
 731 , side_length(2 * extent + 1)
 732 , total_length(side_length * side_length * side_length)
 733 , total_indexed(0)
 734 , last_missing(0)
 735 , stride(1, side_length, side_length * side_length)
 736 , chunks(total_length, nullptr) {
 737         Scan();
 738 }
 739
 740 ChunkIndex::~ChunkIndex() {
 741         Clear();
 742 }
 743
 744 bool ChunkIndex::InRange(const ExactLocation::Coarse &pos) const noexcept {
 745         return Distance(pos) <= extent;
 746 }
 747
 748 bool ChunkIndex::IsBorder(const ExactLocation::Coarse &pos) const noexcept {
 749         return Distance(pos) == extent;
 750 }
 751
 752 int ChunkIndex::Distance(const ExactLocation::Coarse &pos) const noexcept {
 753         return manhattan_radius(pos - base);
 754 }
 755
 756 bool ChunkIndex::HasAllSurrounding(const ExactLocation::Coarse &pos) const noexcept {
 757         ExactLocation::Coarse begin(pos - ExactLocation::Coarse(1));
 758         ExactLocation::Coarse end(pos + ExactLocation::Coarse(2));
 759         for (ExactLocation::Coarse iter(begin); iter.z < end.z; ++iter.z) {
 760                 for (iter.y = begin.y; iter.y < end.y; ++iter.y) {
 761                         for (iter.x = begin.x; iter.x < end.x; ++iter.x) {
 762                                 if (!Get(iter)) return false;
 763                         }
 764                 }
 765         }
 766         return true;
 767 }
 768
 769 int ChunkIndex::IndexOf(const ExactLocation::Coarse &pos) const noexcept {
 770         ExactLocation::Coarse mod_pos(
 771                 GetCol(pos.x),
 772                 GetCol(pos.y),
 773                 GetCol(pos.z)
 774         );
 775         return mod_pos.x * stride.x
 776                 +  mod_pos.y * stride.y
 777                 +  mod_pos.z * stride.z;
 778 }
 779
 780 ExactLocation::Coarse ChunkIndex::PositionOf(int i) const noexcept {
 781         ExactLocation::Coarse zero_pos(
 782                 (i / stride.x) % side_length,
 783                 (i / stride.y) % side_length,
 784                 (i / stride.z) % side_length
 785         );
 786         ExactLocation::Coarse zero_base(
 787                 GetCol(base.x),
 788                 GetCol(base.y),
 789                 GetCol(base.z)
 790         );
 791         ExactLocation::Coarse base_relative(zero_pos - zero_base);
 792         if (base_relative.x > extent) base_relative.x -= side_length;
 793         else if (base_relative.x < -extent) base_relative.x += side_length;
 794         if (base_relative.y > extent) base_relative.y -= side_length;
 795         else if (base_relative.y < -extent) base_relative.y += side_length;
 796         if (base_relative.z > extent) base_relative.z -= side_length;
 797         else if (base_relative.z < -extent) base_relative.z += side_length;
 798         return base + base_relative;
 799 }
 800
 801 Chunk *ChunkIndex::Get(const ExactLocation::Coarse &pos) noexcept {
 802         if (InRange(pos)) {
 803                 return chunks[IndexOf(pos)];
 804         } else {
 805                 return nullptr;
 806         }
 807 }
 808
 809 const Chunk *ChunkIndex::Get(const ExactLocation::Coarse &pos) const noexcept {
 810         if (InRange(pos)) {
 811                 return chunks[IndexOf(pos)];
 812         } else {
 813                 return nullptr;
 814         }
 815 }
 816
 817 void ChunkIndex::Rebase(const ExactLocation::Coarse &new_base) {
 818         if (new_base == base) return;
 819
 820         ExactLocation::Coarse diff(new_base - base);
 821
 822         if (manhattan_radius(diff) > extent) {
 823                 // that's more than half, so probably not worth shifting
 824                 base = new_base;
 825                 Clear();
 826                 Scan();
 827                 store.Clean();
 828                 return;
 829         }
 830
 831         while (diff.x > 0) {
 832                 Shift(Block::FACE_RIGHT);
 833                 --diff.x;
 834         }
 835         while (diff.x < 0) {
 836                 Shift(Block::FACE_LEFT);
 837                 ++diff.x;
 838         }
 839         while (diff.y > 0) {
 840                 Shift(Block::FACE_UP);
 841                 --diff.y;
 842         }
 843         while (diff.y < 0) {
 844                 Shift(Block::FACE_DOWN);
 845                 ++diff.y;
 846         }
 847         while (diff.z > 0) {
 848                 Shift(Block::FACE_FRONT);
 849                 --diff.z;
 850         }
 851         while (diff.z < 0) {
 852                 Shift(Block::FACE_BACK);
 853                 ++diff.z;
 854         }
 855         store.Clean();
 856 }
 857
 858 int ChunkIndex::GetCol(int c) const noexcept {
 859         c %= side_length;
 860         if (c < 0) c += side_length;
 861         return c;
 862 }
 863
 864 void ChunkIndex::Shift(Block::Face f) {
 865         int a_axis = Block::Axis(f);
 866         int b_axis = (a_axis + 1) % 3;
 867         int c_axis = (a_axis + 2) % 3;
 868         int dir = Block::Direction(f);
 869         base[a_axis] += dir;
 870         int a = GetCol(base[a_axis] + (extent * dir));
 871         int a_stride = a * stride[a_axis];
 872         for (int b = 0; b < side_length; ++b) {
 873                 int b_stride = b * stride[b_axis];
 874                 for (int c = 0; c < side_length; ++c) {
 875                         int bc_stride = b_stride + c * stride[c_axis];
 876                         int index = a_stride + bc_stride;
 877                         Unset(index);
 878                         int neighbor = ((a - dir + side_length) % side_length) * stride[a_axis] + bc_stride;
 879                         if (chunks[neighbor] && chunks[neighbor]->HasNeighbor(f)) {
 880                                 Set(index, chunks[neighbor]->GetNeighbor(f));
 881                         }
 882                 }
 883         }
 884 }
 885
 886 void ChunkIndex::Clear() noexcept {
 887         for (int i = 0; i < total_length && total_indexed > 0; ++i) {
 888                 Unset(i);
 889         }
 890 }
 891
 892 void ChunkIndex::Scan() noexcept {
 893         for (Chunk &chunk : store) {
 894                 Register(chunk);
 895         }
 896 }
 897
 898 void ChunkIndex::Register(Chunk &chunk) noexcept {
 899         if (InRange(chunk.Position())) {
 900                 Set(IndexOf(chunk.Position()), chunk);
 901         }
 902 }
 903
 904 void ChunkIndex::Set(int index, Chunk &chunk) noexcept {
 905         Unset(index);
 906         chunks[index] = &chunk;
 907         chunk.Ref();
 908         ++total_indexed;
 909 }
 910
 911 void ChunkIndex::Unset(int index) noexcept {
 912         if (chunks[index]) {
 913                 chunks[index]->UnRef();
 914                 chunks[index] = nullptr;
 915                 --total_indexed;
 916         }
 917 }
 918
 919 ExactLocation::Coarse ChunkIndex::NextMissing() noexcept {
 920         if (MissingChunks() > 0) {
 921                 int roundtrip = last_missing;
 922                 last_missing = (last_missing + 1) % total_length;
 923                 while (chunks[last_missing]) {
 924                         last_missing = (last_missing + 1) % total_length;
 925                         if (last_missing == roundtrip) {
 926                                 break;
 927                         }
 928                 }
 929         }
 930         return PositionOf(last_missing);
 931 }
 932
 933
 934 ChunkStore::ChunkStore(const BlockTypeRegistry &types)
 935 : types(types)
 936 , loaded()
 937 , free()
 938 , indices() {
 939
 940 }
 941
 942 ChunkStore::~ChunkStore() {
 943
 944 }
 945
 946 ChunkIndex &ChunkStore::MakeIndex(const ExactLocation::Coarse &pos, int extent) {
 947         indices.emplace_back(*this, pos, extent);
 948         return indices.back();
 949 }
 950
 951 void ChunkStore::UnregisterIndex(ChunkIndex &index) {
 952         for (auto i = indices.begin(), end = indices.end(); i != end; ++i) {
 953                 if (&*i == &index) {
 954                         indices.erase(i);
 955                         return;
 956                 } else {
 957                         ++i;
 958                 }
 959         }
 960 }
 961
 962 ChunkIndex *ChunkStore::ClosestIndex(const ExactLocation::Coarse &pos) {
 963         ChunkIndex *closest_index = nullptr;
 964         int closest_distance = std::numeric_limits<int>::max();
 965
 966         for (ChunkIndex &index : indices) {
 967                 int distance = index.Distance(pos);
 968                 if (distance < closest_distance) {
 969                         closest_index = &index;
 970                         closest_distance = distance;
 971                 }
 972         }
 973
 974         return closest_index;
 975 }
 976
 977 Chunk *ChunkStore::Get(const ExactLocation::Coarse &pos) {
 978         for (ChunkIndex &index : indices) {
 979                 Chunk *chunk = index.Get(pos);
 980                 if (chunk) {
 981                         return chunk;
 982                 }
 983         }
 984         return nullptr;
 985 }
 986
 987 Chunk *ChunkStore::Allocate(const ExactLocation::Coarse &pos) {
 988         Chunk *chunk = Get(pos);
 989         if (chunk) {
 990                 return chunk;
 991         }
 992         if (free.empty()) {
 993                 loaded.emplace(loaded.begin(), types);
 994         } else {
 995                 loaded.splice(loaded.begin(), free, free.begin());
 996                 loaded.front().Unlink();
 997         }
 998         chunk = &loaded.front();
 999         chunk->Position(pos);
1000         for (ChunkIndex &index : indices) {
1001                 if (index.InRange(pos)) {
1002                         index.Register(*chunk);
1003                 }
1004         }
1005         for (int i = 0; i < Block::FACE_COUNT; ++i) {
1006                 Block::Face face = Block::Face(i);
1007                 ExactLocation::Coarse neighbor_pos(pos + Block::FaceNormal(face));
1008                 Chunk *neighbor = Get(neighbor_pos);
1009                 if (neighbor) {
1010                         chunk->SetNeighbor(face, *neighbor);
1011                 }
1012         }
1013         return chunk;
1014 }
1015
1016 bool ChunkStore::HasMissing() const noexcept {
1017         for (const ChunkIndex &index : indices) {
1018                 if (index.MissingChunks() > 0) {
1019                         return true;
1020                 }
1021         }
1022         return false;
1023 }
1024
1025 int ChunkStore::EstimateMissing() const noexcept {
1026         int missing = 0;
1027         for (const ChunkIndex &index : indices) {
1028                 missing += index.MissingChunks();
1029         }
1030         return missing;
1031 }
1032
1033 ExactLocation::Coarse ChunkStore::NextMissing() noexcept {
1034         for (ChunkIndex &index : indices) {
1035                 if (index.MissingChunks()) {
1036                         return index.NextMissing();
1037                 }
1038         }
1039         return ExactLocation::Coarse(0, 0, 0);
1040 }
1041
1042 void ChunkStore::Clean() {
1043         for (auto i = loaded.begin(), end = loaded.end(); i != end;) {
1044                 if (i->Referenced() || i->ShouldUpdateSave()) {
1045                         ++i;
1046                 } else {
1047                         auto chunk = i;
1048                         ++i;
1049                         free.splice(free.end(), loaded, chunk);
1050                         chunk->Unlink();
1051                         chunk->InvalidateMesh();
1052                 }
1053         }
1054 }
1055
1056 }