]> git.localhorst.tv Git - blank.git/blobdiff - src/chunk.cpp
slight lighting improvement
[blank.git] / src / chunk.cpp
index 66b049f00366e1ea4a91cb2f0f69d7b200c3d48b..a0415fd4f8f735072cf92174eb530d6a7c2423eb 100644 (file)
 
 #include "generator.hpp"
 
+#include <algorithm>
 #include <limits>
 #include <queue>
-#include <glm/gtx/transform.hpp>
 
 
 namespace blank {
 
-Chunk::Chunk(const BlockTypeRegistry &types)
+Chunk::Chunk(const BlockTypeRegistry &types) noexcept
 : types(&types)
-, neighbor{ 0, 0, 0, 0, 0, 0 }
-, blocks()
+, neighbor{0}
+, blocks{}
+, light{0}
 , model()
 , position(0, 0, 0)
 , dirty(false) {
 
 }
 
-Chunk::Chunk(Chunk &&other)
+Chunk::Chunk(Chunk &&other) noexcept
 : types(other.types)
-, blocks(std::move(other.blocks))
 , model(std::move(other.model))
+, position(other.position)
 , dirty(other.dirty) {
-       for (size_t i = 0; i < Block::FACE_COUNT; ++i) {
-               neighbor[i] = other.neighbor[i];
-       }
+       std::copy(other.neighbor, other.neighbor + sizeof(neighbor), neighbor);
+       std::copy(other.blocks, other.blocks + sizeof(blocks), blocks);
+       std::copy(other.light, other.light + sizeof(light), light);
 }
 
-Chunk &Chunk::operator =(Chunk &&other) {
+Chunk &Chunk::operator =(Chunk &&other) noexcept {
        types = other.types;
-       for (size_t i = 0; i < Block::FACE_COUNT; ++i) {
-               neighbor[i] = other.neighbor[i];
-       }
-       blocks = std::move(other.blocks);
+       std::copy(other.neighbor, other.neighbor + sizeof(neighbor), neighbor);
+       std::copy(other.blocks, other.blocks + sizeof(blocks), blocks);
+       std::copy(other.light, other.light + sizeof(light), light);
        model = std::move(other.model);
+       position = other.position;
        dirty = other.dirty;
        return *this;
 }
 
 
-void Chunk::SetNeighbor(Chunk &other) {
-       if (other.position == position - Pos(-1, 0, 0)) {
-               neighbor[Block::FACE_LEFT] = &other;
-               other.neighbor[Block::FACE_RIGHT] = this;
-       } else if (other.position == position - Pos(1, 0, 0)) {
-               neighbor[Block::FACE_RIGHT] = &other;
-               other.neighbor[Block::FACE_LEFT] = this;
-       } else if (other.position == position - Pos(0, -1, 0)) {
-               neighbor[Block::FACE_DOWN] = &other;
-               other.neighbor[Block::FACE_UP] = this;
-       } else if (other.position == position - Pos(0, 1, 0)) {
-               neighbor[Block::FACE_UP] = &other;
-               other.neighbor[Block::FACE_DOWN] = this;
-       } else if (other.position == position - Pos(0, 0, -1)) {
-               neighbor[Block::FACE_BACK] = &other;
-               other.neighbor[Block::FACE_FRONT] = this;
-       } else if (other.position == position - Pos(0, 0, 1)) {
-               neighbor[Block::FACE_FRONT] = &other;
-               other.neighbor[Block::FACE_BACK] = this;
-       }
-}
-
-void Chunk::ClearNeighbors() {
-       for (int i = 0; i < Block::FACE_COUNT; ++i) {
-               neighbor[i] = nullptr;
-       }
-}
-
-void Chunk::Unlink() {
-       if (neighbor[Block::FACE_UP]) {
-               neighbor[Block::FACE_UP]->neighbor[Block::FACE_DOWN] = nullptr;
-       }
-       if (neighbor[Block::FACE_DOWN]) {
-               neighbor[Block::FACE_DOWN]->neighbor[Block::FACE_UP] = nullptr;
-       }
-       if (neighbor[Block::FACE_LEFT]) {
-               neighbor[Block::FACE_LEFT]->neighbor[Block::FACE_RIGHT] = nullptr;
-       }
-       if (neighbor[Block::FACE_RIGHT]) {
-               neighbor[Block::FACE_RIGHT]->neighbor[Block::FACE_LEFT] = nullptr;
-       }
-       if (neighbor[Block::FACE_FRONT]) {
-               neighbor[Block::FACE_FRONT]->neighbor[Block::FACE_BACK] = nullptr;
-       }
-       if (neighbor[Block::FACE_BACK]) {
-               neighbor[Block::FACE_BACK]->neighbor[Block::FACE_FRONT] = nullptr;
-       }
-}
-
-void Chunk::Relink() {
-       if (neighbor[Block::FACE_UP]) {
-               neighbor[Block::FACE_UP]->neighbor[Block::FACE_DOWN] = this;
-       }
-       if (neighbor[Block::FACE_DOWN]) {
-               neighbor[Block::FACE_DOWN]->neighbor[Block::FACE_UP] = this;
-       }
-       if (neighbor[Block::FACE_LEFT]) {
-               neighbor[Block::FACE_LEFT]->neighbor[Block::FACE_RIGHT] = this;
-       }
-       if (neighbor[Block::FACE_RIGHT]) {
-               neighbor[Block::FACE_RIGHT]->neighbor[Block::FACE_LEFT] = this;
-       }
-       if (neighbor[Block::FACE_FRONT]) {
-               neighbor[Block::FACE_FRONT]->neighbor[Block::FACE_BACK] = this;
-       }
-       if (neighbor[Block::FACE_BACK]) {
-               neighbor[Block::FACE_BACK]->neighbor[Block::FACE_FRONT] = this;
-       }
-}
-
-
 namespace {
 
 struct SetNode {
@@ -122,20 +52,16 @@ struct SetNode {
        SetNode(Chunk *chunk, Chunk::Pos pos)
        : chunk(chunk), pos(pos) { }
 
-       int Get() const { return chunk->GetLight(pos); }
-       void Set(int level) { chunk->SetLight(pos, level); }
+       int Get() const noexcept { return chunk->GetLight(pos); }
+       void Set(int level) noexcept { chunk->SetLight(pos, level); }
 
-       bool HasNext(Block::Face face) {
-               const Block *next = chunk->FindNext(pos, face);
-               return next && !chunk->Type(*next).block_light;
+       bool HasNext(Block::Face face) noexcept {
+               const BlockLookup next(chunk, pos, face);
+               return next && !next.GetType().block_light;
        }
-       SetNode GetNext(Block::Face face) {
-               Chunk::Pos next_pos(pos + Block::FaceNormal(face));
-               if (Chunk::InBounds(next_pos)) {
-                       return SetNode(chunk, next_pos);
-               } else {
-                       return SetNode(&chunk->GetNeighbor(face), next_pos - (Block::FaceNormal(face) * Chunk::Extent()));
-               }
+       SetNode GetNext(Block::Face face) noexcept {
+               const BlockLookup next(chunk, pos, face);
+               return SetNode(&next.GetChunk(), next.GetBlockPos());
        }
 
 };
@@ -151,14 +77,19 @@ struct UnsetNode
        UnsetNode(const SetNode &set)
        : SetNode(set), level(Get()) { }
 
-       UnsetNode GetNext(Block::Face face) { return UnsetNode(SetNode::GetNext(face)); }
+
+       bool HasNext(Block::Face face) noexcept {
+               const BlockLookup next(chunk, pos, face);
+               return next;
+       }
+       UnsetNode GetNext(Block::Face face) noexcept { return UnsetNode(SetNode::GetNext(face)); }
 
 };
 
 std::queue<SetNode> light_queue;
 std::queue<UnsetNode> dark_queue;
 
-void work_light() {
+void work_light() noexcept {
        while (!light_queue.empty()) {
                SetNode node = light_queue.front();
                light_queue.pop();
@@ -176,7 +107,7 @@ void work_light() {
        }
 }
 
-void work_dark() {
+void work_dark() noexcept {
        while (!dark_queue.empty()) {
                UnsetNode node = dark_queue.front();
                dark_queue.pop();
@@ -194,12 +125,11 @@ void work_dark() {
                        }
                }
        }
-       work_light();
 }
 
 }
 
-void Chunk::SetBlock(int index, const Block &block) {
+void Chunk::SetBlock(int index, const Block &block) noexcept {
        const BlockType &old_type = Type(blocks[index]);
        const BlockType &new_type = Type(block);
 
@@ -207,31 +137,34 @@ void Chunk::SetBlock(int index, const Block &block) {
 
        if (&old_type == &new_type) return;
 
-       if (new_type.luminosity > 0) {
-               if (GetLight(index) < new_type.luminosity) {
-                       SetLight(index, new_type.luminosity);
-                       light_queue.emplace(this, ToPos(index));
-                       work_light();
-               }
-       } else if (new_type.block_light && GetLight(index) != 0) {
-               SetLight(index, 0);
+       if (new_type.luminosity > old_type.luminosity) {
+               // light added
+               SetLight(index, new_type.luminosity);
+               light_queue.emplace(this, ToPos(index));
+               work_light();
+       } else if (new_type.luminosity < old_type.luminosity) {
+               // light removed
                dark_queue.emplace(this, ToPos(index));
+               SetLight(index, 0);
                work_dark();
-       } else if (old_type.block_light && !new_type.block_light) {
+               SetLight(index, new_type.luminosity);
+               light_queue.emplace(this, ToPos(index));
+               work_light();
+       } else if (new_type.block_light && !old_type.block_light) {
+               // obstacle added
+               if (GetLight(index) > 0) {
+                       dark_queue.emplace(this, ToPos(index));
+                       SetLight(index, 0);
+                       work_dark();
+                       work_light();
+               }
+       } else if (!new_type.block_light && old_type.block_light) {
+               // obstacle removed
                int level = 0;
                for (int face = 0; face < Block::FACE_COUNT; ++face) {
-                       Pos next_pos(ToPos(index) + Block::FaceNormal(Block::Face(face)));
-                       int next_level = 0;
-                       if (InBounds(next_pos)) {
-                               next_level = GetLight(next_pos);
-                       } else {
-                               if (HasNeighbor(Block::Face(face))) {
-                                       next_pos -= (Block::FaceNormal(Block::Face(face)) * Chunk::Extent());
-                                       next_level = GetNeighbor(Block::Face(face)).GetLight(next_pos);
-                               }
-                       }
-                       if (level < next_level) {
-                               level = next_level;
+                       BlockLookup next_block(this, ToPos(index), Block::Face(face));
+                       if (next_block) {
+                               level = std::min(level, next_block.GetLight());
                        }
                }
                if (level > 1) {
@@ -242,35 +175,250 @@ void Chunk::SetBlock(int index, const Block &block) {
        }
 }
 
-const Block *Chunk::FindNext(const Pos &pos, Block::Face face) const {
-       Pos next_pos(pos + Block::FaceNormal(face));
-       if (InBounds(next_pos)) {
-               return &BlockAt(pos + Block::FaceNormal(face));
-       } else if (HasNeighbor(face)) {
-               return &GetNeighbor(face).BlockAt(next_pos - (Block::FaceNormal(face) * Extent()));
-       } else {
-               return nullptr;
+void Chunk::SetNeighbor(Chunk &other) noexcept {
+       if (other.position == position + Pos(-1, 0, 0)) {
+               if (neighbor[Block::FACE_LEFT] != &other) {
+                       neighbor[Block::FACE_LEFT] = &other;
+                       other.neighbor[Block::FACE_RIGHT] = this;
+                       for (int z = 0; z < Depth(); ++z) {
+                               for (int y = 0; y < Height(); ++y) {
+                                       Pos my_pos(0, y, z);
+                                       Pos other_pos(Width() - 1, y, z);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       } else if (other.position == position + Pos(1, 0, 0)) {
+               if (neighbor[Block::FACE_RIGHT] != &other) {
+                       neighbor[Block::FACE_RIGHT] = &other;
+                       other.neighbor[Block::FACE_LEFT] = this;
+                       for (int z = 0; z < Depth(); ++z) {
+                               for (int y = 0; y < Height(); ++y) {
+                                       Pos my_pos(Width() - 1, y, z);
+                                       Pos other_pos(0, y, z);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       } else if (other.position == position + Pos(0, -1, 0)) {
+               if (neighbor[Block::FACE_DOWN] != &other) {
+                       neighbor[Block::FACE_DOWN] = &other;
+                       other.neighbor[Block::FACE_UP] = this;
+                       for (int z = 0; z < Depth(); ++z) {
+                               for (int x = 0; x < Width(); ++x) {
+                                       Pos my_pos(x, 0, z);
+                                       Pos other_pos(x, Height() - 1, z);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       } else if (other.position == position + Pos(0, 1, 0)) {
+               if (neighbor[Block::FACE_UP] != &other) {
+                       neighbor[Block::FACE_UP] = &other;
+                       other.neighbor[Block::FACE_DOWN] = this;
+                       for (int z = 0; z < Depth(); ++z) {
+                               for (int x = 0; x < Width(); ++x) {
+                                       Pos my_pos(x, Height() - 1, z);
+                                       Pos other_pos(x, 0, z);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       } else if (other.position == position + Pos(0, 0, -1)) {
+               if (neighbor[Block::FACE_BACK] != &other) {
+                       neighbor[Block::FACE_BACK] = &other;
+                       other.neighbor[Block::FACE_FRONT] = this;
+                       for (int y = 0; y < Height(); ++y) {
+                               for (int x = 0; x < Width(); ++x) {
+                                       Pos my_pos(x, y, 0);
+                                       Pos other_pos(x, y, Depth() - 1);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       } else if (other.position == position + Pos(0, 0, 1)) {
+               if (neighbor[Block::FACE_FRONT] != &other) {
+                       neighbor[Block::FACE_FRONT] = &other;
+                       other.neighbor[Block::FACE_BACK] = this;
+                       for (int y = 0; y < Height(); ++y) {
+                               for (int x = 0; x < Width(); ++x) {
+                                       Pos my_pos(x, y, Depth() - 1);
+                                       Pos other_pos(x, y, 0);
+                                       if (GetLight(my_pos) > 0) {
+                                               light_queue.emplace(this, my_pos);
+                                       }
+                                       if (other.GetLight(other_pos) > 0) {
+                                               light_queue.emplace(&other, other_pos);
+                                       }
+                               }
+                       }
+                       work_light();
+               }
+       }
+}
+
+void Chunk::ClearNeighbors() noexcept {
+       for (int i = 0; i < Block::FACE_COUNT; ++i) {
+               neighbor[i] = nullptr;
+       }
+}
+
+void Chunk::Unlink() noexcept {
+       for (int face = 0; face < Block::FACE_COUNT; ++face) {
+               if (neighbor[face]) {
+                       neighbor[face]->neighbor[Block::Opposite(Block::Face(face))] = nullptr;
+               }
+       }
+}
+
+void Chunk::Relink() noexcept {
+       for (int face = 0; face < Block::FACE_COUNT; ++face) {
+               if (neighbor[face]) {
+                       neighbor[face]->neighbor[Block::Opposite(Block::Face(face))] = this;
+               }
        }
 }
 
 
-void Chunk::SetLight(int index, int level) {
-       light[index] = level;
+void Chunk::SetLight(int index, int level) noexcept {
+       if (light[index] != level) {
+               light[index] = level;
+               Invalidate();
+       }
 }
 
-int Chunk::GetLight(int index) const {
+int Chunk::GetLight(int index) const noexcept {
        return light[index];
 }
 
+float Chunk::GetVertexLight(int index, const BlockModel::Position &vtx, const Model::Normal &norm) const noexcept {
+       float light = GetLight(index);
+       Chunk::Pos pos(ToPos(index));
+
+       Block::Face direct_face(Block::NormalFace(norm));
+       // tis okay
+       BlockLookup direct(const_cast<Chunk *>(this), pos, Block::NormalFace(norm));
+       if (direct) {
+               float direct_light = direct.GetLight();
+               if (direct_light > light) {
+                       light = direct_light;
+               }
+       } else {
+               return light;
+       }
 
-bool Chunk::IsSurface(const Pos &pos) const {
+       if (Type(BlockAt(index)).luminosity > 0 || direct.GetType().block_light) {
+               return light;
+       }
+
+       Block::Face edge[2];
+       switch (Block::Axis(direct_face)) {
+               case 0: // X
+                       edge[0] = (vtx.y - pos.y) > 0.5f ? Block::FACE_UP : Block::FACE_DOWN;
+                       edge[1] = (vtx.z - pos.z) > 0.5f ? Block::FACE_FRONT : Block::FACE_BACK;
+                       break;
+               case 1: // Y
+                       edge[0] = (vtx.z - pos.z) > 0.5f ? Block::FACE_FRONT : Block::FACE_BACK;
+                       edge[1] = (vtx.x - pos.x) > 0.5f ? Block::FACE_RIGHT : Block::FACE_LEFT;
+                       break;
+               case 2: // Z
+                       edge[0] = (vtx.x - pos.x) > 0.5f ? Block::FACE_RIGHT : Block::FACE_LEFT;
+                       edge[1] = (vtx.y - pos.y) > 0.5f ? Block::FACE_UP : Block::FACE_DOWN;
+                       break;
+       }
+
+       int num = 1;
+       int occlusion = 0;
+
+       BlockLookup next[2] = {
+               direct.Next(edge[0]),
+               direct.Next(edge[1]),
+       };
+
+       if (next[0]) {
+               if (next[0].GetType().block_light) {
+                       ++occlusion;
+               } else {
+                       light += next[0].GetLight();
+                       ++num;
+               }
+       }
+       if (next[1]) {
+               if (next[1].GetType().block_light) {
+                       ++occlusion;
+               } else {
+                       light += next[1].GetLight();
+                       ++num;
+               }
+       }
+       if (occlusion < 2) {
+               if (next[0]) {
+                       BlockLookup corner = next[0].Next(edge[1]);
+                       if (corner) {
+                               if (corner.GetType().block_light) {
+                                       ++occlusion;
+                               } else {
+                                       light += corner.GetLight();
+                                       ++num;
+                               }
+                       }
+               } else if (next[1]) {
+                       BlockLookup corner = next[1].Next(edge[0]);
+                       if (corner) {
+                               if (corner.GetType().block_light) {
+                                       ++occlusion;
+                               } else {
+                                       light += corner.GetLight();
+                                       ++num;
+                               }
+                       }
+               }
+       } else {
+               ++occlusion;
+       }
+
+       return (light / num) - (occlusion * 0.8f);
+}
+
+
+bool Chunk::IsSurface(const Pos &pos) const noexcept {
        const Block &block = BlockAt(pos);
        if (!Type(block).visible) {
                return false;
        }
        for (int face = 0; face < Block::FACE_COUNT; ++face) {
-               const Block *next = FindNext(pos, Block::Face(face));
-               if (!next || !Type(*next).visible) {
+               BlockLookup next = BlockLookup(const_cast<Chunk *>(this), pos, Block::Face(face));
+               if (!next || !next.GetType().visible) {
                        return true;
                }
        }
@@ -278,13 +426,7 @@ bool Chunk::IsSurface(const Pos &pos) const {
 }
 
 
-void Chunk::Allocate() {
-       blocks.resize(Size(), Block(0));
-       light.resize(Size(), 0);
-}
-
-
-void Chunk::Draw() {
+void Chunk::Draw() noexcept {
        if (dirty) {
                Update();
        }
@@ -298,7 +440,7 @@ bool Chunk::Intersection(
        int &blkid,
        float &dist,
        glm::vec3 &normal
-) const {
+) const noexcept {
        // TODO: should be possible to heavily optimize this
        int id = 0;
        blkid = -1;
@@ -330,28 +472,20 @@ bool Chunk::Intersection(
        }
 }
 
-void Chunk::Position(const Pos &pos) {
-       position = pos;
-}
-
-glm::mat4 Chunk::Transform(const Pos &offset) const {
-       return glm::translate((position - offset) * Extent());
-}
-
 
 namespace {
 
-Model::Buffer buf;
+BlockModel::Buffer buf;
 
 }
 
-void Chunk::CheckUpdate() {
+void Chunk::CheckUpdate() noexcept {
        if (dirty) {
                Update();
        }
 }
 
-void Chunk::Update() {
+void Chunk::Update() noexcept {
        int vtx_count = 0, idx_count = 0;
        for (const auto &block : blocks) {
                const Shape *shape = Type(block).shape;
@@ -361,124 +495,126 @@ void Chunk::Update() {
        buf.Clear();
        buf.Reserve(vtx_count, idx_count);
 
-       Model::Index vtx_counter = 0;
+       BlockModel::Index vtx_counter = 0;
        for (size_t i = 0; i < Size(); ++i) {
                const BlockType &type = Type(blocks[i]);
 
-               if (!type.visible || Obstructed(i)) continue;
+               if (!type.visible || Obstructed(i).All()) continue;
 
-               type.FillModel(buf, ToTransform(i), vtx_counter);
+               type.FillBlockModel(buf, ToTransform(i), vtx_counter);
+               size_t vtx_begin = vtx_counter;
                vtx_counter += type.shape->VertexCount();
+
+               for (size_t vtx = vtx_begin; vtx < vtx_counter; ++vtx) {
+                       buf.lights.emplace_back(GetVertexLight(
+                               i,
+                               buf.vertices[vtx],
+                               type.shape->VertexNormal(vtx - vtx_begin, blocks[i].Transform())
+                       ));
+               }
        }
 
        model.Update(buf);
        dirty = false;
 }
 
-bool Chunk::Obstructed(int idx) const {
+Block::FaceSet Chunk::Obstructed(int idx) const noexcept {
        Chunk::Pos pos(ToPos(idx));
+       Block::FaceSet result;
 
-       Chunk::Pos left_pos(pos + Chunk::Pos(-1, 0, 0));
-       const Block *left_block = nullptr;
-       if (InBounds(left_pos)) {
-               left_block = &BlockAt(left_pos);
-       } else if (HasNeighbor(Block::FACE_LEFT)) {
-               left_pos += Chunk::Pos(Width(), 0, 0);
-               left_block = &GetNeighbor(Block::FACE_LEFT).BlockAt(left_pos);
-       } else {
-               return false;
-       }
-       if (!Type(*left_block).FaceFilled(*left_block, Block::FACE_RIGHT)) {
-               return false;
+       for (int f = 0; f < Block::FACE_COUNT; ++f) {
+               Block::Face face = Block::Face(f);
+               BlockLookup next(const_cast<Chunk *>(this), pos, face);
+               if (next && next.GetType().FaceFilled(next.GetBlock(), Block::Opposite(face))) {
+                       result.Set(face);
+               }
        }
 
-       Chunk::Pos right_pos(pos + Chunk::Pos(1, 0, 0));
-       const Block *right_block = nullptr;
-       if (InBounds(right_pos)) {
-               right_block = &BlockAt(right_pos);
-       } else if (HasNeighbor(Block::FACE_RIGHT)) {
-               right_pos += Chunk::Pos(-Width(), 0, 0);
-               right_block = &GetNeighbor(Block::FACE_RIGHT).BlockAt(right_pos);
-       } else {
-               return false;
-       }
-       if (!Type(*right_block).FaceFilled(*right_block, Block::FACE_LEFT)) {
-               return false;
-       }
+       return result;
+}
 
-       Chunk::Pos down_pos(pos + Chunk::Pos(0, -1, 0));
-       const Block *down_block = nullptr;
-       if (InBounds(down_pos)) {
-               down_block = &BlockAt(down_pos);
-       } else if (HasNeighbor(Block::FACE_DOWN)) {
-               down_pos += Chunk::Pos(0, Height(), 0);
-               down_block = &GetNeighbor(Block::FACE_DOWN).BlockAt(down_pos);
-       } else {
-               return false;
-       }
-       if (!Type(*down_block).FaceFilled(*down_block, Block::FACE_UP)) {
-               return false;
-       }
+glm::mat4 Chunk::ToTransform(int idx) const noexcept {
+       return glm::translate(ToCoords(idx)) * blocks[idx].Transform();
+}
 
-       Chunk::Pos up_pos(pos + Chunk::Pos(0, 1, 0));
-       const Block *up_block = nullptr;
-       if (InBounds(up_pos)) {
-               up_block = &BlockAt(up_pos);
-       } else if (HasNeighbor(Block::FACE_UP)) {
-               up_pos += Chunk::Pos(0, -Height(), 0);
-               up_block = &GetNeighbor(Block::FACE_UP).BlockAt(up_pos);
-       } else {
-               return false;
+
+BlockLookup::BlockLookup(Chunk *c, const Chunk::Pos &p) noexcept
+: chunk(c), pos(p) {
+       while (pos.x >= Chunk::Width()) {
+               if (chunk->HasNeighbor(Block::FACE_RIGHT)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_RIGHT);
+                       pos.x -= Chunk::Width();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-       if (!Type(*up_block).FaceFilled(*up_block, Block::FACE_DOWN)) {
-               return false;
+       while (pos.x < 0) {
+               if (chunk->HasNeighbor(Block::FACE_LEFT)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_LEFT);
+                       pos.x += Chunk::Width();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-
-       Chunk::Pos back_pos(pos + Chunk::Pos(0, 0, -1));
-       const Block *back_block = nullptr;
-       if (InBounds(back_pos)) {
-               back_block = &BlockAt(back_pos);
-       } else if (HasNeighbor(Block::FACE_BACK)) {
-               back_pos += Chunk::Pos(0, 0, Depth());
-               back_block = &GetNeighbor(Block::FACE_BACK).BlockAt(back_pos);
-       } else {
-               return false;
+       while (pos.y >= Chunk::Height()) {
+               if (chunk->HasNeighbor(Block::FACE_UP)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_UP);
+                       pos.y -= Chunk::Height();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-       if (!Type(*back_block).FaceFilled(*back_block, Block::FACE_FRONT)) {
-               return false;
+       while (pos.y < 0) {
+               if (chunk->HasNeighbor(Block::FACE_DOWN)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_DOWN);
+                       pos.y += Chunk::Height();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-
-       Chunk::Pos front_pos(pos + Chunk::Pos(0, 0, 1));
-       const Block *front_block = nullptr;
-       if (InBounds(front_pos)) {
-               front_block = &BlockAt(front_pos);
-       } else if (HasNeighbor(Block::FACE_FRONT)) {
-               front_pos += Chunk::Pos(0, 0, -Depth());
-               front_block = &GetNeighbor(Block::FACE_FRONT).BlockAt(front_pos);
-       } else {
-               return false;
+       while (pos.z >= Chunk::Depth()) {
+               if (chunk->HasNeighbor(Block::FACE_FRONT)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_FRONT);
+                       pos.z -= Chunk::Depth();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-       if (!Type(*front_block).FaceFilled(*front_block, Block::FACE_BACK)) {
-               return false;
+       while (pos.z < 0) {
+               if (chunk->HasNeighbor(Block::FACE_BACK)) {
+                       chunk = &chunk->GetNeighbor(Block::FACE_BACK);
+                       pos.z += Chunk::Depth();
+               } else {
+                       chunk = nullptr;
+                       return;
+               }
        }
-
-       return true;
 }
 
-glm::mat4 Chunk::ToTransform(int idx) const {
-       return glm::translate(glm::mat4(1.0f), ToCoords(idx)) * blocks[idx].Transform();
+BlockLookup::BlockLookup(Chunk *c, const Chunk::Pos &p, Block::Face face) noexcept
+: chunk(c), pos(p) {
+       pos += Block::FaceNormal(face);
+       if (!Chunk::InBounds(pos)) {
+               pos -= Block::FaceNormal(face) * Chunk::Extent();
+               chunk = &chunk->GetNeighbor(face);
+       }
 }
 
 
-ChunkLoader::ChunkLoader(const BlockTypeRegistry &reg, const Generator &gen)
+ChunkLoader::ChunkLoader(const Config &config, const BlockTypeRegistry &reg, const Generator &gen) noexcept
 : base(0, 0, 0)
 , reg(reg)
 , gen(gen)
 , loaded()
 , to_generate()
 , to_free()
-, load_dist(6)
-, unload_dist(8) {
+, load_dist(config.load_dist)
+, unload_dist(config.unload_dist) {
 
 }
 
@@ -486,10 +622,10 @@ namespace {
 
 struct ChunkLess {
 
-       explicit ChunkLess(const Chunk::Pos &base)
+       explicit ChunkLess(const Chunk::Pos &base) noexcept
        : base(base) { }
 
-       bool operator ()(const Chunk::Pos &a, const Chunk::Pos &b) const {
+       bool operator ()(const Chunk::Pos &a, const Chunk::Pos &b) const noexcept {
                Chunk::Pos da(base - a);
                Chunk::Pos db(base - b);
                return
@@ -513,6 +649,42 @@ void ChunkLoader::Generate(const Chunk::Pos &from, const Chunk::Pos &to) {
                                } else if (pos == base) {
                                        Generate(pos);
 
+                               //      light testing
+                               //      for (int i = 0; i < 16; ++i) {
+                               //              for (int j = 0; j < 16; ++j) {
+                               //                      loaded.back().SetBlock(Chunk::Pos{  i, j,  0 }, Block(1));
+                               //                      loaded.back().SetBlock(Chunk::Pos{  i, j, 15 }, Block(1));
+                               //                      loaded.back().SetBlock(Chunk::Pos{  0, j,  i }, Block(1));
+                               //                      loaded.back().SetBlock(Chunk::Pos{ 15, j,  i }, Block(1));
+                               //              }
+                               //      }
+                               //      loaded.back().SetBlock(Chunk::Pos{  1,  0,  1 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 14,  0,  1 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  1,  0, 14 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 14,  0, 14 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  1, 15,  1 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 14, 15,  1 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  1, 15, 14 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 14, 15, 14 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  7,  7,  0 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  8,  7,  0 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  7,  8,  0 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  8,  8,  0 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  7,  7, 15 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  8,  7, 15 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  7,  8, 15 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  8,  8, 15 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  0,  7,  7 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  0,  7,  8 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  0,  8,  7 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{  0,  8,  8 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 15,  7,  7 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 15,  7,  8 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 15,  8,  7 }, Block(13));
+                               //      loaded.back().SetBlock(Chunk::Pos{ 15,  8,  8 }, Block(13));
+                               //      loaded.back().Invalidate();
+                               //      loaded.back().CheckUpdate();
+
                                //      orientation testing
                                //      for (int i = 0; i < Block::FACE_COUNT; ++i) {
                                //              for (int j = 0; j < Block::TURN_COUNT; ++j) {
@@ -534,22 +706,22 @@ Chunk &ChunkLoader::Generate(const Chunk::Pos &pos) {
        loaded.emplace_back(reg);
        Chunk &chunk = loaded.back();
        chunk.Position(pos);
-       Insert(chunk);
        gen(chunk);
+       Insert(chunk);
        return chunk;
 }
 
-void ChunkLoader::Insert(Chunk &chunk) {
+void ChunkLoader::Insert(Chunk &chunk) noexcept {
        for (Chunk &other : loaded) {
                chunk.SetNeighbor(other);
        }
 }
 
-void ChunkLoader::Remove(Chunk &chunk) {
+void ChunkLoader::Remove(Chunk &chunk) noexcept {
        chunk.Unlink();
 }
 
-Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) {
+Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) noexcept {
        for (Chunk &chunk : loaded) {
                if (chunk.Position() == pos) {
                        return &chunk;
@@ -558,7 +730,7 @@ Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) {
        return nullptr;
 }
 
-bool ChunkLoader::Queued(const Chunk::Pos &pos) {
+bool ChunkLoader::Queued(const Chunk::Pos &pos) noexcept {
        for (const Chunk::Pos &chunk : to_generate) {
                if (chunk == pos) {
                        return true;
@@ -567,7 +739,7 @@ bool ChunkLoader::Queued(const Chunk::Pos &pos) {
        return nullptr;
 }
 
-bool ChunkLoader::Known(const Chunk::Pos &pos) {
+bool ChunkLoader::Known(const Chunk::Pos &pos) noexcept {
        if (Loaded(pos)) return true;
        return Queued(pos);
 }
@@ -627,38 +799,31 @@ void ChunkLoader::GenerateSurrounding(const Chunk::Pos &pos) {
 }
 
 void ChunkLoader::Update() {
-       bool reused = false;
-       if (!to_generate.empty()) {
-               Chunk::Pos pos(to_generate.front());
-
-               for (auto iter(to_free.begin()), end(to_free.end()); iter != end; ++iter) {
-                       if (iter->Position() == pos) {
-                               iter->Relink();
-                               loaded.splice(loaded.end(), to_free, iter);
-                               reused = true;
-                               break;
-                       }
-               }
+       if (to_generate.empty()) {
+               return;
+       }
 
-               if (!reused) {
-                       if (to_free.empty()) {
-                               loaded.emplace_back(reg);
-                       } else {
-                               to_free.front().ClearNeighbors();
-                               loaded.splice(loaded.end(), to_free, to_free.begin());
-                               reused = true;
-                       }
-                       Chunk &chunk = loaded.back();
-                       chunk.Position(pos);
-                       Insert(chunk);
-                       gen(chunk);
+       Chunk::Pos pos(to_generate.front());
+       to_generate.pop_front();
+
+       for (auto iter(to_free.begin()), end(to_free.end()); iter != end; ++iter) {
+               if (iter->Position() == pos) {
+                       iter->Relink();
+                       loaded.splice(loaded.end(), to_free, iter);
+                       return;
                }
-               to_generate.pop_front();
        }
 
-       if (!reused && !to_free.empty()) {
-               to_free.pop_front();
+       if (to_free.empty()) {
+               loaded.emplace_back(reg);
+       } else {
+               to_free.front().ClearNeighbors();
+               loaded.splice(loaded.end(), to_free, to_free.begin());
        }
+       Chunk &chunk = loaded.back();
+       chunk.Position(pos);
+       gen(chunk);
+       Insert(chunk);
 }
 
 }