src/world/World.cpp

   1 #include "World.hpp"
   2
   3 #include "EntityCollision.hpp"
   4 #include "WorldCollision.hpp"
   5 #include "../app/Assets.hpp"
   6 #include "../graphics/Format.hpp"
   7 #include "../graphics/Viewport.hpp"
   8
   9 #include <algorithm>
  10 #include <limits>
  11 #include <glm/gtx/io.hpp>
  12 #include <glm/gtx/transform.hpp>
  13
  14
  15 namespace blank {
  16
  17 World::World(const BlockTypeRegistry &types, const Config &config, const WorldSave &save)
  18 : block_type(types)
  19 , generate(config.gen)
  20 , chunks(config.load, types, generate, save)
  21 , player()
  22 , entities()
  23 , light_direction(config.light_direction)
  24 , fog_density(config.fog_density) {
  25         generate.Space(0);
  26         generate.Light(13);
  27         generate.Solids({ 1, 4, 7, 10 });
  28
  29         player = &AddEntity();
  30         player->Name("player");
  31         player->Bounds({ { -0.5f, -0.5f, -0.5f }, { 0.5f, 0.5f, 0.5f } });
  32         player->WorldCollidable(true);
  33         player->Position(config.spawn);
  34
  35         chunks.QueueSurrounding(player->ChunkCoords());
  36 }
  37
  38
  39 namespace {
  40
  41 struct Candidate {
  42         Chunk *chunk;
  43         float dist;
  44 };
  45
  46 bool CandidateLess(const Candidate &a, const Candidate &b) {
  47         return a.dist < b.dist;
  48 }
  49
  50 std::vector<Candidate> candidates;
  51
  52 }
  53
  54 bool World::Intersection(
  55         const Ray &ray,
  56         const glm::mat4 &M,
  57         const Chunk::Pos &reference,
  58         WorldCollision &coll
  59 ) {
  60         candidates.clear();
  61
  62         for (Chunk &cur_chunk : chunks.Loaded()) {
  63                 float cur_dist;
  64                 if (cur_chunk.Intersection(ray, M * cur_chunk.Transform(reference), cur_dist)) {
  65                         candidates.push_back({ &cur_chunk, cur_dist });
  66                 }
  67         }
  68
  69         if (candidates.empty()) return false;
  70
  71         std::sort(candidates.begin(), candidates.end(), CandidateLess);
  72
  73         coll.chunk = nullptr;
  74         coll.block = -1;
  75         coll.depth = std::numeric_limits<float>::infinity();
  76
  77         for (Candidate &cand : candidates) {
  78                 if (cand.dist > coll.depth) continue;
  79                 WorldCollision cur_coll;
  80                 if (cand.chunk->Intersection(ray, M * cand.chunk->Transform(reference), cur_coll)) {
  81                         if (cur_coll.depth < coll.depth) {
  82                                 coll = cur_coll;
  83                         }
  84                 }
  85         }
  86
  87         return coll.chunk;
  88 }
  89
  90 bool World::Intersection(
  91         const Ray &ray,
  92         const glm::mat4 &M,
  93         const Entity &reference,
  94         EntityCollision &coll
  95 ) {
  96         coll.entity = nullptr;
  97         coll.depth = std::numeric_limits<float>::infinity();
  98         for (Entity &cur_entity : entities) {
  99                 if (&cur_entity == &reference) {
 100                         continue;
 101                 }
 102                 float cur_dist;
 103                 glm::vec3 cur_normal;
 104                 if (blank::Intersection(ray, cur_entity.Bounds(), M * cur_entity.Transform(reference.ChunkCoords()), &cur_dist, &cur_normal)) {
 105                         // TODO: fine grained check goes here? maybe?
 106                         if (cur_dist < coll.depth) {
 107                                 coll.entity = &cur_entity;
 108                                 coll.depth = cur_dist;
 109                                 coll.normal = cur_normal;
 110                         }
 111                 }
 112         }
 113
 114         return coll.entity;
 115 }
 116
 117 bool World::Intersection(const Entity &e, std::vector<WorldCollision> &col) {
 118         AABB box = e.Bounds();
 119         Chunk::Pos reference = e.ChunkCoords();
 120         glm::mat4 M = e.Transform(reference);
 121         bool any = false;
 122         for (Chunk &cur_chunk : chunks.Loaded()) {
 123                 if (manhattan_radius(cur_chunk.Position() - e.ChunkCoords()) > 1) {
 124                         // chunk is not one of the 3x3x3 surrounding the entity
 125                         // since there's no entity which can extent over 16 blocks, they can be skipped
 126                         continue;
 127                 }
 128                 if (cur_chunk.Intersection(box, M, cur_chunk.Transform(reference), col)) {
 129                         any = true;
 130                 }
 131         }
 132         return any;
 133 }
 134
 135
 136 Chunk &World::PlayerChunk() {
 137         return chunks.ForceLoad(player->ChunkCoords());
 138 }
 139
 140
 141 namespace {
 142
 143 std::vector<WorldCollision> col;
 144
 145 }
 146
 147 void World::Update(int dt) {
 148         for (Entity &entity : entities) {
 149                 entity.Update(dt);
 150         }
 151         for (Entity &entity : entities) {
 152                 col.clear();
 153                 if (entity.WorldCollidable() && Intersection(entity, col)) {
 154                         // entity collides with the world
 155                         Resolve(entity, col);
 156                 }
 157         }
 158         for (auto iter = entities.begin(), end = entities.end(); iter != end;) {
 159                 if (iter->CanRemove()) {
 160                         iter = entities.erase(iter);
 161                 } else {
 162                         ++iter;
 163                 }
 164         }
 165         chunks.Rebase(player->ChunkCoords());
 166         chunks.Update(dt);
 167 }
 168
 169 void World::Resolve(Entity &e, std::vector<WorldCollision> &col) {
 170         // determine displacement for each cardinal axis and move entity accordingly
 171         glm::vec3 min_disp(0.0f);
 172         glm::vec3 max_disp(0.0f);
 173         for (const WorldCollision &c : col) {
 174                 if (!c.Blocks()) continue;
 175                 glm::vec3 local_disp(c.normal * c.depth);
 176                 // swap if neccessary (normal may point away from the entity)
 177                 if (dot(c.normal, e.Position() - c.BlockCoords()) < 0) {
 178                         local_disp *= -1;
 179                 }
 180                 min_disp = min(min_disp, local_disp);
 181                 max_disp = max(max_disp, local_disp);
 182         }
 183         // for each axis
 184         // if only one direction is set, use that as the final
 185         // if both directions are set, use average
 186         glm::vec3 final_disp(0.0f);
 187         for (int axis = 0; axis < 3; ++axis) {
 188                 if (std::abs(min_disp[axis]) > std::numeric_limits<float>::epsilon()) {
 189                         if (std::abs(max_disp[axis]) > std::numeric_limits<float>::epsilon()) {
 190                                 final_disp[axis] = (min_disp[axis] + max_disp[axis]) * 0.5f;
 191                         } else {
 192                                 final_disp[axis] = min_disp[axis];
 193                         }
 194                 } else if (std::abs(max_disp[axis]) > std::numeric_limits<float>::epsilon()) {
 195                         final_disp[axis] = max_disp[axis];
 196                 }
 197         }
 198         e.Move(final_disp);
 199 }
 200
 201
 202 void World::Render(Viewport &viewport) {
 203         DirectionalLighting &entity_prog = viewport.EntityProgram();
 204         entity_prog.SetLightDirection(light_direction);
 205         entity_prog.SetFogDensity(fog_density);
 206
 207         for (Entity &entity : entities) {
 208                 entity.Render(entity.ChunkTransform(player->ChunkCoords()), entity_prog);
 209         }
 210 }
 211
 212 }