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         bool any = false;
 404         float penetration;
 405         glm::vec3 normal;
 406
 407         if (!blank::Intersection(box, Mbox, Bounds(), Mchunk, penetration, normal)) {
 408                 return false;
 409         }
 410         for (int idx = 0, z = 0; z < side; ++z) {
 411                 for (int y = 0; y < side; ++y) {
 412                         for (int x = 0; x < side; ++x, ++idx) {
 413                                 const BlockType &type = Type(idx);
 414                                 if (!type.collision || !type.shape) {
 415                                         continue;
 416                                 }
 417                                 if (type.shape->Intersects(Mchunk * ToTransform(RoughLocation::Fine(x, y, z), idx), box, Mbox, penetration, normal)) {
 418                                         col.emplace_back(this, idx, penetration, normal);
 419                                         any = true;
 420                                 }
 421                         }
 422                 }
 423         }
 424         return any;
 425 }
 426
 427
 428 namespace {
 429
 430 BlockMesh::Buffer buf;
 431
 432 }
 433
 434 void Chunk::Update(BlockMesh &model) noexcept {
 435         int vtx_count = 0, idx_count = 0;
 436         for (const auto &block : blocks) {
 437                 const BlockType &type = Type(block);
 438                 if (type.visible && type.shape) {
 439                         vtx_count += type.shape->VertexCount();
 440                         idx_count += type.shape->IndexCount();
 441                 }
 442         }
 443         buf.Clear();
 444         buf.Reserve(vtx_count, idx_count);
 445
 446         if (idx_count > 0) {
 447                 int idx = 0;
 448                 BlockMesh::Index vtx_counter = 0;
 449                 for (size_t z = 0; z < side; ++z) {
 450                         for (size_t y = 0; y < side; ++y) {
 451                                 for (size_t x = 0; x < side; ++x, ++idx) {
 452                                         const BlockType &type = Type(BlockAt(idx));
 453                                         const RoughLocation::Fine pos(x, y, z);
 454
 455                                         if (!type.visible || !type.shape || Obstructed(pos).All()) continue;
 456
 457                                         type.FillBlockMesh(buf, ToTransform(pos, idx), vtx_counter);
 458                                         size_t vtx_begin = vtx_counter;
 459                                         vtx_counter += type.shape->VertexCount();
 460
 461                                         for (size_t vtx = vtx_begin; vtx < vtx_counter; ++vtx) {
 462                                                 buf.lights.emplace_back(GetVertexLight(
 463                                                         pos,
 464                                                         buf.vertices[vtx],
 465                                                         type.shape->VertexNormal(vtx - vtx_begin, BlockAt(idx).Transform())
 466                                                 ));
 467                                         }
 468                                 }
 469                         }
 470                 }
 471         }
 472
 473         model.Update(buf);
 474         ClearMesh();
 475 }
 476
 477 Block::FaceSet Chunk::Obstructed(const RoughLocation::Fine &pos) const noexcept {
 478         Block::FaceSet result;
 479
 480         for (int f = 0; f < Block::FACE_COUNT; ++f) {
 481                 Block::Face face = Block::Face(f);
 482                 BlockLookup next(const_cast<Chunk *>(this), pos, face);
 483                 if (next && next.GetType().FaceFilled(next.GetBlock(), Block::Opposite(face))) {
 484                         result.Set(face);
 485                 }
 486         }
 487
 488         return result;
 489 }
 490
 491 glm::mat4 Chunk::ToTransform(const RoughLocation::Fine &pos, int idx) const noexcept {
 492         return glm::translate(ToCoords(pos)) * BlockAt(idx).Transform();
 493 }
 494
 495
 496 BlockLookup::BlockLookup(Chunk *c, const RoughLocation::Fine &p) noexcept
 497 : chunk(c), pos(p) {
 498         while (pos.x >= Chunk::side) {
 499                 if (chunk->HasNeighbor(Block::FACE_RIGHT)) {
 500                         chunk = &chunk->GetNeighbor(Block::FACE_RIGHT);
 501                         pos.x -= Chunk::side;
 502                 } else {
 503                         chunk = nullptr;
 504                         return;
 505                 }
 506         }
 507         while (pos.x < 0) {
 508                 if (chunk->HasNeighbor(Block::FACE_LEFT)) {
 509                         chunk = &chunk->GetNeighbor(Block::FACE_LEFT);
 510                         pos.x += Chunk::side;
 511                 } else {
 512                         chunk = nullptr;
 513                         return;
 514                 }
 515         }
 516         while (pos.y >= Chunk::side) {
 517                 if (chunk->HasNeighbor(Block::FACE_UP)) {
 518                         chunk = &chunk->GetNeighbor(Block::FACE_UP);
 519                         pos.y -= Chunk::side;
 520                 } else {
 521                         chunk = nullptr;
 522                         return;
 523                 }
 524         }
 525         while (pos.y < 0) {
 526                 if (chunk->HasNeighbor(Block::FACE_DOWN)) {
 527                         chunk = &chunk->GetNeighbor(Block::FACE_DOWN);
 528                         pos.y += Chunk::side;
 529                 } else {
 530                         chunk = nullptr;
 531                         return;
 532                 }
 533         }
 534         while (pos.z >= Chunk::side) {
 535                 if (chunk->HasNeighbor(Block::FACE_FRONT)) {
 536                         chunk = &chunk->GetNeighbor(Block::FACE_FRONT);
 537                         pos.z -= Chunk::side;
 538                 } else {
 539                         chunk = nullptr;
 540                         return;
 541                 }
 542         }
 543         while (pos.z < 0) {
 544                 if (chunk->HasNeighbor(Block::FACE_BACK)) {
 545                         chunk = &chunk->GetNeighbor(Block::FACE_BACK);
 546                         pos.z += Chunk::side;
 547                 } else {
 548                         chunk = nullptr;
 549                         return;
 550                 }
 551         }
 552 }
 553
 554 BlockLookup::BlockLookup(Chunk *c, const RoughLocation::Fine &p, Block::Face face) noexcept
 555 : chunk(c), pos(p) {
 556         pos += Block::FaceNormal(face);
 557         if (!Chunk::InBounds(pos)) {
 558                 pos -= Block::FaceNormal(face) * ExactLocation::Extent();
 559                 chunk = &chunk->GetNeighbor(face);
 560         }
 561 }
 562
 563
 564 ChunkLoader::ChunkLoader(
 565         ChunkStore &store,
 566         const Generator &gen,
 567         const WorldSave &save
 568 ) noexcept
 569 : store(store)
 570 , gen(gen)
 571 , save(save) {
 572
 573 }
 574
 575 void ChunkLoader::Update(int dt) {
 576         // check if there's chunks waiting to be loaded
 577         // load until one of load or generation limits was hit
 578         constexpr int max_load = 10;
 579         constexpr int max_gen = 1;
 580         int loaded = 0;
 581         int generated = 0;
 582         while (loaded < max_load && generated < max_gen && store.HasMissing()) {
 583                 if (LoadOne()) {
 584                         ++generated;
 585                 } else {
 586                         ++loaded;
 587                 }
 588         }
 589
 590         // store a few chunks as well
 591         constexpr int max_save = 10;
 592         int saved = 0;
 593         for (Chunk &chunk : store) {
 594                 if (chunk.ShouldUpdateSave()) {
 595                         save.Write(chunk);
 596                         ++saved;
 597                         if (saved >= max_save) {
 598                                 break;
 599                         }
 600                 }
 601         }
 602 }
 603
 604 int ChunkLoader::ToLoad() const noexcept {
 605         return store.EstimateMissing();
 606 }
 607
 608 bool ChunkLoader::LoadOne() {
 609         if (!store.HasMissing()) return false;
 610
 611         ExactLocation::Coarse pos = store.NextMissing();
 612         Chunk *chunk = store.Allocate(pos);
 613         if (!chunk) {
 614                 // chunk store corrupted?
 615                 return false;
 616         }
 617
 618         bool generated = false;
 619         if (save.Exists(pos)) {
 620                 save.Read(*chunk);
 621         } else {
 622                 gen(*chunk);
 623                 generated = true;
 624         }
 625
 626         ChunkIndex *index = store.ClosestIndex(pos);
 627         if (!index) {
 628                 return generated;
 629         }
 630
 631         ExactLocation::Coarse begin(pos - ExactLocation::Coarse(1));
 632         ExactLocation::Coarse end(pos + ExactLocation::Coarse(2));
 633         for (ExactLocation::Coarse iter(begin); iter.z < end.z; ++iter.z) {
 634                 for (iter.y = begin.y; iter.y < end.y; ++iter.y) {
 635                         for (iter.x = begin.x; iter.x < end.x; ++iter.x) {
 636                                 if (index->IsBorder(iter)) continue;
 637                                 Chunk *light_chunk = index->Get(iter);
 638                                 if (!light_chunk) continue;
 639                                 if (index->HasAllSurrounding(iter)) {
 640                                         if (!light_chunk->Lighted()) {
 641                                                 light_chunk->ScanLights();
 642                                         } else {
 643                                                 light_chunk->InvalidateMesh();
 644                                         }
 645                                 }
 646                         }
 647                 }
 648         }
 649
 650         return generated;
 651 }
 652
 653 void ChunkLoader::LoadN(std::size_t n) {
 654         std::size_t end = std::min(n, std::size_t(ToLoad()));
 655         for (std::size_t i = 0; i < end && store.HasMissing(); ++i) {
 656                 LoadOne();
 657         }
 658 }
 659
 660
 661 ChunkRenderer::ChunkRenderer(ChunkIndex &index)
 662 : index(index)
 663 , models(index.TotalChunks())
 664 , block_tex()
 665 , fog_density(0.0f) {
 666
 667 }
 668
 669 ChunkRenderer::~ChunkRenderer() {
 670
 671 }
 672
 673 int ChunkRenderer::MissingChunks() const noexcept {
 674         return index.MissingChunks();
 675 }
 676
 677 void ChunkRenderer::LoadTextures(const AssetLoader &loader, const ResourceIndex &tex_index) {
 678         block_tex.Bind();
 679         loader.LoadTextures(tex_index, block_tex);
 680         block_tex.FilterNearest();
 681 }
 682
 683 void ChunkRenderer::Update(int dt) {
 684         for (int i = 0, updates = 0; updates < dt && i < index.TotalChunks(); ++i) {
 685                 if (!index[i]) continue;
 686                 if (!index[i]->Lighted() && index.HasAllSurrounding(index[i]->Position())) {
 687                         index[i]->ScanLights();
 688                 }
 689                 if (index[i]->ShouldUpdateMesh()) {
 690                         index[i]->Update(models[i]);
 691                         ++updates;
 692                 }
 693         }
 694 }
 695
 696 void ChunkRenderer::Render(Viewport &viewport) {
 697         BlockLighting &chunk_prog = viewport.ChunkProgram();
 698         chunk_prog.SetTexture(block_tex);
 699         chunk_prog.SetFogDensity(fog_density);
 700
 701         for (int i = 0; i < index.TotalChunks(); ++i) {
 702                 if (!index[i]) continue;
 703                 glm::mat4 m(index[i]->Transform(index.Base()));
 704                 glm::mat4 mvp(chunk_prog.GetVP() * m);
 705                 if (!CullTest(Chunk::Bounds(), mvp)) {
 706                         if (index[i]->ShouldUpdateMesh()) {
 707                                 index[i]->Update(models[i]);
 708                         }
 709                         chunk_prog.SetM(m);
 710                         models[i].Draw();
 711                 }
 712         }
 713 }
 714
 715
 716 ChunkIndex::ChunkIndex(ChunkStore &store, const ExactLocation::Coarse &base, int extent)
 717 : store(store)
 718 , base(base)
 719 , extent(extent)
 720 , side_length(2 * extent + 1)
 721 , total_length(side_length * side_length * side_length)
 722 , total_indexed(0)
 723 , last_missing(0)
 724 , stride(1, side_length, side_length * side_length)
 725 , chunks(total_length, nullptr) {
 726         Scan();
 727 }
 728
 729 ChunkIndex::~ChunkIndex() {
 730         Clear();
 731 }
 732
 733 bool ChunkIndex::InRange(const ExactLocation::Coarse &pos) const noexcept {
 734         return Distance(pos) <= extent;
 735 }
 736
 737 bool ChunkIndex::IsBorder(const ExactLocation::Coarse &pos) const noexcept {
 738         return Distance(pos) == extent;
 739 }
 740
 741 int ChunkIndex::Distance(const ExactLocation::Coarse &pos) const noexcept {
 742         return manhattan_radius(pos - base);
 743 }
 744
 745 bool ChunkIndex::HasAllSurrounding(const ExactLocation::Coarse &pos) const noexcept {
 746         ExactLocation::Coarse begin(pos - ExactLocation::Coarse(1));
 747         ExactLocation::Coarse end(pos + ExactLocation::Coarse(2));
 748         for (ExactLocation::Coarse iter(begin); iter.z < end.z; ++iter.z) {
 749                 for (iter.y = begin.y; iter.y < end.y; ++iter.y) {
 750                         for (iter.x = begin.x; iter.x < end.x; ++iter.x) {
 751                                 if (!Get(iter)) return false;
 752                         }
 753                 }
 754         }
 755         return true;
 756 }
 757
 758 int ChunkIndex::IndexOf(const ExactLocation::Coarse &pos) const noexcept {
 759         ExactLocation::Coarse mod_pos(
 760                 GetCol(pos.x),
 761                 GetCol(pos.y),
 762                 GetCol(pos.z)
 763         );
 764         return mod_pos.x * stride.x
 765                 +  mod_pos.y * stride.y
 766                 +  mod_pos.z * stride.z;
 767 }
 768
 769 ExactLocation::Coarse ChunkIndex::PositionOf(int i) const noexcept {
 770         ExactLocation::Coarse zero_pos(
 771                 (i / stride.x) % side_length,
 772                 (i / stride.y) % side_length,
 773                 (i / stride.z) % side_length
 774         );
 775         ExactLocation::Coarse zero_base(
 776                 GetCol(base.x),
 777                 GetCol(base.y),
 778                 GetCol(base.z)
 779         );
 780         ExactLocation::Coarse base_relative(zero_pos - zero_base);
 781         if (base_relative.x > extent) base_relative.x -= side_length;
 782         else if (base_relative.x < -extent) base_relative.x += side_length;
 783         if (base_relative.y > extent) base_relative.y -= side_length;
 784         else if (base_relative.y < -extent) base_relative.y += side_length;
 785         if (base_relative.z > extent) base_relative.z -= side_length;
 786         else if (base_relative.z < -extent) base_relative.z += side_length;
 787         return base + base_relative;
 788 }
 789
 790 Chunk *ChunkIndex::Get(const ExactLocation::Coarse &pos) noexcept {
 791         if (InRange(pos)) {
 792                 return chunks[IndexOf(pos)];
 793         } else {
 794                 return nullptr;
 795         }
 796 }
 797
 798 const Chunk *ChunkIndex::Get(const ExactLocation::Coarse &pos) const noexcept {
 799         if (InRange(pos)) {
 800                 return chunks[IndexOf(pos)];
 801         } else {
 802                 return nullptr;
 803         }
 804 }
 805
 806 void ChunkIndex::Rebase(const ExactLocation::Coarse &new_base) {
 807         if (new_base == base) return;
 808
 809         ExactLocation::Coarse diff(new_base - base);
 810
 811         if (manhattan_radius(diff) > extent) {
 812                 // that's more than half, so probably not worth shifting
 813                 base = new_base;
 814                 Clear();
 815                 Scan();
 816                 store.Clean();
 817                 return;
 818         }
 819
 820         while (diff.x > 0) {
 821                 Shift(Block::FACE_RIGHT);
 822                 --diff.x;
 823         }
 824         while (diff.x < 0) {
 825                 Shift(Block::FACE_LEFT);
 826                 ++diff.x;
 827         }
 828         while (diff.y > 0) {
 829                 Shift(Block::FACE_UP);
 830                 --diff.y;
 831         }
 832         while (diff.y < 0) {
 833                 Shift(Block::FACE_DOWN);
 834                 ++diff.y;
 835         }
 836         while (diff.z > 0) {
 837                 Shift(Block::FACE_FRONT);
 838                 --diff.z;
 839         }
 840         while (diff.z < 0) {
 841                 Shift(Block::FACE_BACK);
 842                 ++diff.z;
 843         }
 844         store.Clean();
 845 }
 846
 847 int ChunkIndex::GetCol(int c) const noexcept {
 848         c %= side_length;
 849         if (c < 0) c += side_length;
 850         return c;
 851 }
 852
 853 void ChunkIndex::Shift(Block::Face f) {
 854         int a_axis = Block::Axis(f);
 855         int b_axis = (a_axis + 1) % 3;
 856         int c_axis = (a_axis + 2) % 3;
 857         int dir = Block::Direction(f);
 858         base[a_axis] += dir;
 859         int a = GetCol(base[a_axis] + (extent * dir));
 860         int a_stride = a * stride[a_axis];
 861         for (int b = 0; b < side_length; ++b) {
 862                 int b_stride = b * stride[b_axis];
 863                 for (int c = 0; c < side_length; ++c) {
 864                         int bc_stride = b_stride + c * stride[c_axis];
 865                         int index = a_stride + bc_stride;
 866                         Unset(index);
 867                         int neighbor = ((a - dir + side_length) % side_length) * stride[a_axis] + bc_stride;
 868                         if (chunks[neighbor] && chunks[neighbor]->HasNeighbor(f)) {
 869                                 Set(index, chunks[neighbor]->GetNeighbor(f));
 870                         }
 871                 }
 872         }
 873 }
 874
 875 void ChunkIndex::Clear() noexcept {
 876         for (int i = 0; i < total_length && total_indexed > 0; ++i) {
 877                 Unset(i);
 878         }
 879 }
 880
 881 void ChunkIndex::Scan() noexcept {
 882         for (Chunk &chunk : store) {
 883                 Register(chunk);
 884         }
 885 }
 886
 887 void ChunkIndex::Register(Chunk &chunk) noexcept {
 888         if (InRange(chunk.Position())) {
 889                 Set(IndexOf(chunk.Position()), chunk);
 890         }
 891 }
 892
 893 void ChunkIndex::Set(int index, Chunk &chunk) noexcept {
 894         Unset(index);
 895         chunks[index] = &chunk;
 896         chunk.Ref();
 897         ++total_indexed;
 898 }
 899
 900 void ChunkIndex::Unset(int index) noexcept {
 901         if (chunks[index]) {
 902                 chunks[index]->UnRef();
 903                 chunks[index] = nullptr;
 904                 --total_indexed;
 905         }
 906 }
 907
 908 ExactLocation::Coarse ChunkIndex::NextMissing() noexcept {
 909         if (MissingChunks() > 0) {
 910                 int roundtrip = last_missing;
 911                 last_missing = (last_missing + 1) % total_length;
 912                 while (chunks[last_missing]) {
 913                         last_missing = (last_missing + 1) % total_length;
 914                         if (last_missing == roundtrip) {
 915                                 break;
 916                         }
 917                 }
 918         }
 919         return PositionOf(last_missing);
 920 }
 921
 922
 923 ChunkStore::ChunkStore(const BlockTypeRegistry &types)
 924 : types(types)
 925 , loaded()
 926 , free()
 927 , indices() {
 928
 929 }
 930
 931 ChunkStore::~ChunkStore() {
 932
 933 }
 934
 935 ChunkIndex &ChunkStore::MakeIndex(const ExactLocation::Coarse &pos, int extent) {
 936         indices.emplace_back(*this, pos, extent);
 937         return indices.back();
 938 }
 939
 940 void ChunkStore::UnregisterIndex(ChunkIndex &index) {
 941         for (auto i = indices.begin(), end = indices.end(); i != end; ++i) {
 942                 if (&*i == &index) {
 943                         indices.erase(i);
 944                         return;
 945                 } else {
 946                         ++i;
 947                 }
 948         }
 949 }
 950
 951 ChunkIndex *ChunkStore::ClosestIndex(const ExactLocation::Coarse &pos) {
 952         ChunkIndex *closest_index = nullptr;
 953         int closest_distance = std::numeric_limits<int>::max();
 954
 955         for (ChunkIndex &index : indices) {
 956                 int distance = index.Distance(pos);
 957                 if (distance < closest_distance) {
 958                         closest_index = &index;
 959                         closest_distance = distance;
 960                 }
 961         }
 962
 963         return closest_index;
 964 }
 965
 966 Chunk *ChunkStore::Get(const ExactLocation::Coarse &pos) {
 967         for (ChunkIndex &index : indices) {
 968                 Chunk *chunk = index.Get(pos);
 969                 if (chunk) {
 970                         return chunk;
 971                 }
 972         }
 973         return nullptr;
 974 }
 975
 976 Chunk *ChunkStore::Allocate(const ExactLocation::Coarse &pos) {
 977         Chunk *chunk = Get(pos);
 978         if (chunk) {
 979                 return chunk;
 980         }
 981         if (free.empty()) {
 982                 loaded.emplace(loaded.begin(), types);
 983         } else {
 984                 loaded.splice(loaded.begin(), free, free.begin());
 985                 loaded.front().Unlink();
 986         }
 987         chunk = &loaded.front();
 988         chunk->Position(pos);
 989         for (ChunkIndex &index : indices) {
 990                 if (index.InRange(pos)) {
 991                         index.Register(*chunk);
 992                 }
 993         }
 994         for (int i = 0; i < Block::FACE_COUNT; ++i) {
 995                 Block::Face face = Block::Face(i);
 996                 ExactLocation::Coarse neighbor_pos(pos + Block::FaceNormal(face));
 997                 Chunk *neighbor = Get(neighbor_pos);
 998                 if (neighbor) {
 999                         chunk->SetNeighbor(face, *neighbor);
1000                 }
1001         }
1002         return chunk;
1003 }
1004
1005 bool ChunkStore::HasMissing() const noexcept {
1006         for (const ChunkIndex &index : indices) {
1007                 if (index.MissingChunks() > 0) {
1008                         return true;
1009                 }
1010         }
1011         return false;
1012 }
1013
1014 int ChunkStore::EstimateMissing() const noexcept {
1015         int missing = 0;
1016         for (const ChunkIndex &index : indices) {
1017                 missing += index.MissingChunks();
1018         }
1019         return missing;
1020 }
1021
1022 ExactLocation::Coarse ChunkStore::NextMissing() noexcept {
1023         for (ChunkIndex &index : indices) {
1024                 if (index.MissingChunks()) {
1025                         return index.NextMissing();
1026                 }
1027         }
1028         return ExactLocation::Coarse(0, 0, 0);
1029 }
1030
1031 void ChunkStore::Clean() {
1032         for (auto i = loaded.begin(), end = loaded.end(); i != end;) {
1033                 if (i->Referenced() || i->ShouldUpdateSave()) {
1034                         ++i;
1035                 } else {
1036                         auto chunk = i;
1037                         ++i;
1038                         free.splice(free.end(), loaded, chunk);
1039                         chunk->Unlink();
1040                         chunk->InvalidateMesh();
1041                 }
1042         }
1043 }
1044
1045 }