X-Git-Url: https://git.localhorst.tv/?a=blobdiff_plain;f=src%2Fchunk.cpp;h=3824a471ac321936bb8c794bc560105cef282525;hb=e53a0e2e711a7d8bd9b0ddacd1360aa14370643f;hp=04c64f26738170a98b64345ddfc9712463ce70d5;hpb=374843f5b3ae60c0d02704a8da5100ac8abe7f1a;p=blank.git

diff --git a/src/chunk.cpp b/src/chunk.cpp
index 04c64f2..3824a47 100644
--- a/src/chunk.cpp
+++ b/src/chunk.cpp
@@ -2,44 +2,437 @@
 
 #include "generator.hpp"
 
+#include <algorithm>
 #include <limits>
-#include <glm/gtx/transform.hpp>
+#include <queue>
 
 
 namespace blank {
 
-Chunk::Chunk(const BlockTypeRegistry &types)
+constexpr int Chunk::width;
+constexpr int Chunk::height;
+constexpr int Chunk::depth;
+constexpr int Chunk::size;
+
+
+Chunk::Chunk(const BlockTypeRegistry &types) noexcept
 : types(&types)
-, 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) {
-
+	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;
-	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::Allocate() {
-	blocks.resize(Size());
+namespace {
+
+struct SetNode {
+
+	Chunk *chunk;
+	Chunk::Pos pos;
+
+	SetNode(Chunk *chunk, Chunk::Pos pos)
+	: chunk(chunk), pos(pos) { }
+
+	int Get() const noexcept { return chunk->GetLight(pos); }
+	void Set(int level) noexcept { chunk->SetLight(pos, level); }
+
+	bool HasNext(Block::Face face) noexcept {
+		const BlockLookup next(chunk, pos, face);
+		return next && !next.GetType().block_light;
+	}
+	SetNode GetNext(Block::Face face) noexcept {
+		const BlockLookup next(chunk, pos, face);
+		return SetNode(&next.GetChunk(), next.GetBlockPos());
+	}
+
+};
+
+struct UnsetNode
+: public SetNode {
+
+	int level;
+
+	UnsetNode(Chunk *chunk, Chunk::Pos pos)
+	: SetNode(chunk, pos), level(Get()) { }
+
+	UnsetNode(const SetNode &set)
+	: SetNode(set), level(Get()) { }
+
+
+	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() noexcept {
+	while (!light_queue.empty()) {
+		SetNode node = light_queue.front();
+		light_queue.pop();
+
+		int level = node.Get() - 1;
+		for (int face = 0; face < Block::FACE_COUNT; ++face) {
+			if (node.HasNext(Block::Face(face))) {
+				SetNode other = node.GetNext(Block::Face(face));
+				if (other.Get() < level) {
+					other.Set(level);
+					light_queue.emplace(other);
+				}
+			}
+		}
+	}
+}
+
+void work_dark() noexcept {
+	while (!dark_queue.empty()) {
+		UnsetNode node = dark_queue.front();
+		dark_queue.pop();
+
+		for (int face = 0; face < Block::FACE_COUNT; ++face) {
+			if (node.HasNext(Block::Face(face))) {
+				UnsetNode other = node.GetNext(Block::Face(face));
+				// TODO: if there a light source here with the same level this will err
+				if (other.Get() != 0 && other.Get() < node.level) {
+					other.Set(0);
+					dark_queue.emplace(other);
+				} else {
+					light_queue.emplace(other);
+				}
+			}
+		}
+	}
+}
+
+}
+
+void Chunk::SetBlock(int index, const Block &block) noexcept {
+	const BlockType &old_type = Type(blocks[index]);
+	const BlockType &new_type = Type(block);
+
+	blocks[index] = block;
+
+	if (&old_type == &new_type) return;
+
+	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();
+		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) {
+			BlockLookup next_block(this, ToPos(index), Block::Face(face));
+			if (next_block) {
+				level = std::min(level, next_block.GetLight());
+			}
+		}
+		if (level > 1) {
+			SetLight(index, level - 1);
+			light_queue.emplace(this, ToPos(index));
+			work_light();
+		}
+	}
+}
+
+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) noexcept {
+	if (light[index] != level) {
+		light[index] = level;
+		Invalidate();
+	}
+}
+
+int Chunk::GetLight(int index) const noexcept {
+	return light[index];
+}
+
+float Chunk::GetVertexLight(const Pos &pos, const BlockModel::Position &vtx, const Model::Normal &norm) const noexcept {
+	int index = ToIndex(pos);
+	float light = GetLight(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;
+	}
+
+	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) {
+		BlockLookup next = BlockLookup(const_cast<Chunk *>(this), pos, Block::Face(face));
+		if (!next || !next.GetType().visible) {
+			return true;
+		}
+	}
+	return false;
 }
 
 
-void Chunk::Draw() {
+void Chunk::Draw() noexcept {
 	if (dirty) {
 		Update();
 	}
@@ -50,107 +443,190 @@ void Chunk::Draw() {
 bool Chunk::Intersection(
 	const Ray &ray,
 	const glm::mat4 &M,
-	int *blkid,
-	float *dist,
-	glm::vec3 *normal) const {
-	{ // rough check
-		if (!blank::Intersection(ray, Bounds(), M)) {
-			return false;
-		}
-	}
-
-	if (!blkid && !dist && !normal) {
-		return true;
-	}
-
+	int &blkid,
+	float &dist,
+	glm::vec3 &normal
+) const noexcept {
 	// TODO: should be possible to heavily optimize this
-	int id = 0;
-	int closest_id = -1;
-	float closest_dist = std::numeric_limits<float>::infinity();
-	glm::vec3 closest_normal(0, 1, 0);
-	for (int z = 0; z < Depth(); ++z) {
-		for (int y = 0; y < Height(); ++y) {
-			for (int x = 0; x < Width(); ++x, ++id) {
-				if (!Type(blocks[id]).visible) {
+	int idx = 0;
+	blkid = -1;
+	dist = std::numeric_limits<float>::infinity();
+	for (int z = 0; z < depth; ++z) {
+		for (int y = 0; y < height; ++y) {
+			for (int x = 0; x < width; ++x, ++idx) {
+				const BlockType &type = Type(idx);
+				if (!type.visible) {
 					continue;
 				}
 				float cur_dist;
 				glm::vec3 cur_norm;
-				Block::Pos pos(float(x) + 0.5f, float(y) + 0.5f, float(z) + 0.5f);
-				if (Type(blocks[id]).shape->Intersects(ray, glm::translate(M, pos), cur_dist, cur_norm)) {
-					if (cur_dist < closest_dist) {
-						closest_id = id;
-						closest_dist = cur_dist;
-						closest_normal = cur_norm;
+				if (type.shape->Intersects(ray, M * ToTransform(Pos(x, y, z), idx), cur_dist, cur_norm)) {
+					if (cur_dist < dist) {
+						blkid = idx;
+						dist = cur_dist;
+						normal = cur_norm;
 					}
 				}
 			}
 		}
 	}
 
-	if (closest_id < 0) {
+	if (blkid < 0) {
 		return false;
+	} else {
+		normal = glm::vec3(BlockAt(blkid).Transform() * glm::vec4(normal, 0.0f));
+		return true;
 	}
-
-	if (blkid) {
-		*blkid = closest_id;
-	}
-	if (dist) {
-		*dist = closest_dist;
-	}
-	if (normal) {
-		*normal = closest_normal;
-	}
-	return true;
 }
 
-void Chunk::Position(const Pos &pos) {
-	position = pos;
-}
 
-glm::mat4 Chunk::Transform(const Pos &offset) const {
-	return glm::translate((position - offset) * Extent());
-}
+namespace {
 
+BlockModel::Buffer buf;
 
-void Chunk::CheckUpdate() {
+}
+
+void Chunk::CheckUpdate() noexcept {
 	if (dirty) {
 		Update();
 	}
-	model.CheckUpdate();
 }
 
-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;
 		vtx_count += shape->VertexCount();
 		idx_count += shape->VertexIndexCount();
 	}
-	model.Clear();
-	model.Reserve(vtx_count, idx_count);
-
-	Model::Index vtx_counter = 0;
-	for (size_t i = 0; i < Size(); ++i) {
-		const BlockType &type = Type(blocks[i]);
-		type.FillModel(model, ToCoords(i), vtx_counter);
-		vtx_counter += type.shape->VertexCount();
+	buf.Clear();
+	buf.Reserve(vtx_count, idx_count);
+
+	int idx = 0;
+	BlockModel::Index vtx_counter = 0;
+	for (size_t z = 0; z < depth; ++z) {
+		for (size_t y = 0; y < height; ++y) {
+			for (size_t x = 0; x < width; ++x, ++idx) {
+				const BlockType &type = Type(BlockAt(idx));
+				const Pos pos(x, y, z);
+
+				if (!type.visible || Obstructed(pos).All()) continue;
+
+				type.FillBlockModel(buf, ToTransform(pos, idx), 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(
+						pos,
+						buf.vertices[vtx],
+						type.shape->VertexNormal(vtx - vtx_begin, BlockAt(idx).Transform())
+					));
+				}
+			}
+		}
 	}
 
-	model.Invalidate();
+	model.Update(buf);
 	dirty = false;
 }
 
+Block::FaceSet Chunk::Obstructed(const Pos &pos) const noexcept {
+	Block::FaceSet result;
+
+	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);
+		}
+	}
+
+	return result;
+}
+
+glm::mat4 Chunk::ToTransform(const Pos &pos, int idx) const noexcept {
+	return glm::translate(ToCoords(pos)) * BlockAt(idx).Transform();
+}
+
+
+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;
+		}
+	}
+	while (pos.x < 0) {
+		if (chunk->HasNeighbor(Block::FACE_LEFT)) {
+			chunk = &chunk->GetNeighbor(Block::FACE_LEFT);
+			pos.x += Chunk::width;
+		} else {
+			chunk = nullptr;
+			return;
+		}
+	}
+	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;
+		}
+	}
+	while (pos.y < 0) {
+		if (chunk->HasNeighbor(Block::FACE_DOWN)) {
+			chunk = &chunk->GetNeighbor(Block::FACE_DOWN);
+			pos.y += Chunk::height;
+		} else {
+			chunk = nullptr;
+			return;
+		}
+	}
+	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;
+		}
+	}
+	while (pos.z < 0) {
+		if (chunk->HasNeighbor(Block::FACE_BACK)) {
+			chunk = &chunk->GetNeighbor(Block::FACE_BACK);
+			pos.z += Chunk::depth;
+		} else {
+			chunk = nullptr;
+			return;
+		}
+	}
+}
+
+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(4)
-, unload_dist(5) {
+, load_dist(config.load_dist)
+, unload_dist(config.unload_dist) {
 
 }
 
@@ -158,12 +634,12 @@ namespace {
 
 struct ChunkLess {
 
-	explicit ChunkLess(const Chunk::Pos &base)
+	explicit ChunkLess(const Chunk::Pos &base) noexcept
 	: base(base) { }
 
-	bool operator ()(const Chunk &a, const Chunk &b) const {
-		Chunk::Pos da(base - a.Position());
-		Chunk::Pos db(base - b.Position());
+	bool operator ()(const Chunk::Pos &a, const Chunk::Pos &b) const noexcept {
+		Chunk::Pos da(base - a);
+		Chunk::Pos db(base - b);
 		return
 			da.x * da.x + da.y * da.y + da.z * da.z <
 			db.x * db.x + db.y * db.y + db.z * db.z;
@@ -182,13 +658,55 @@ void ChunkLoader::Generate(const Chunk::Pos &from, const Chunk::Pos &to) {
 				Chunk::Pos pos(x, y, z);
 				if (Known(pos)) {
 					continue;
-				} else if (x == 0 && y == 0 && z == 0) {
-					loaded.emplace_back(reg);
-					loaded.back().Position(pos);
-					gen(loaded.back());
+				} 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) {
+				//			loaded.back().BlockAt(512 * j + 2 * i) = Block(3 * (j + 1), Block::Face(i), Block::Turn(j));
+				//		}
+				//	}
+				//	loaded.back().Invalidate();
+				//	loaded.back().CheckUpdate();
 				} else {
-					to_generate.emplace_back(reg);
-					to_generate.back().Position(pos);
+					to_generate.emplace_back(pos);
 				}
 			}
 		}
@@ -196,7 +714,26 @@ void ChunkLoader::Generate(const Chunk::Pos &from, const Chunk::Pos &to) {
 	to_generate.sort(ChunkLess(base));
 }
 
-Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) {
+Chunk &ChunkLoader::Generate(const Chunk::Pos &pos) {
+	loaded.emplace_back(reg);
+	Chunk &chunk = loaded.back();
+	chunk.Position(pos);
+	gen(chunk);
+	Insert(chunk);
+	return chunk;
+}
+
+void ChunkLoader::Insert(Chunk &chunk) noexcept {
+	for (Chunk &other : loaded) {
+		chunk.SetNeighbor(other);
+	}
+}
+
+void ChunkLoader::Remove(Chunk &chunk) noexcept {
+	chunk.Unlink();
+}
+
+Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) noexcept {
 	for (Chunk &chunk : loaded) {
 		if (chunk.Position() == pos) {
 			return &chunk;
@@ -205,19 +742,17 @@ Chunk *ChunkLoader::Loaded(const Chunk::Pos &pos) {
 	return nullptr;
 }
 
-Chunk *ChunkLoader::Queued(const Chunk::Pos &pos) {
-	for (Chunk &chunk : to_generate) {
-		if (chunk.Position() == pos) {
-			return &chunk;
+bool ChunkLoader::Queued(const Chunk::Pos &pos) noexcept {
+	for (const Chunk::Pos &chunk : to_generate) {
+		if (chunk == pos) {
+			return true;
 		}
 	}
 	return nullptr;
 }
 
-Chunk *ChunkLoader::Known(const Chunk::Pos &pos) {
-	Chunk *chunk = Loaded(pos);
-	if (chunk) return chunk;
-
+bool ChunkLoader::Known(const Chunk::Pos &pos) noexcept {
+	if (Loaded(pos)) return true;
 	return Queued(pos);
 }
 
@@ -227,16 +762,14 @@ Chunk &ChunkLoader::ForceLoad(const Chunk::Pos &pos) {
 		return *chunk;
 	}
 
-	chunk = Queued(pos);
-	if (chunk) {
-		gen(*chunk);
-		return *chunk;
+	for (auto iter(to_generate.begin()), end(to_generate.end()); iter != end; ++iter) {
+		if (*iter == pos) {
+			to_generate.erase(iter);
+			break;
+		}
 	}
 
-	loaded.emplace_back(reg);
-	loaded.back().Position(pos);
-	gen(loaded.back());
-	return loaded.back();
+	return Generate(pos);
 }
 
 void ChunkLoader::Rebase(const Chunk::Pos &new_base) {
@@ -251,6 +784,7 @@ void ChunkLoader::Rebase(const Chunk::Pos &new_base) {
 				|| std::abs(base.y - iter->Position().y) > unload_dist
 				|| std::abs(base.z - iter->Position().z) > unload_dist) {
 			auto saved = iter;
+			Remove(*saved);
 			++iter;
 			to_free.splice(to_free.end(), loaded, saved);
 		} else {
@@ -259,28 +793,49 @@ void ChunkLoader::Rebase(const Chunk::Pos &new_base) {
 	}
 	// abort far away queued chunks
 	for (auto iter(to_generate.begin()), end(to_generate.end()); iter != end;) {
-		if (std::abs(base.x - iter->Position().x) > unload_dist
-				|| std::abs(base.y - iter->Position().y) > unload_dist
-				|| std::abs(base.z - iter->Position().z) > unload_dist) {
+		if (std::abs(base.x - iter->x) > unload_dist
+				|| std::abs(base.y - iter->y) > unload_dist
+				|| std::abs(base.z - iter->z) > unload_dist) {
 			iter = to_generate.erase(iter);
 		} else {
 			++iter;
 		}
 	}
 	// add missing new chunks
+	GenerateSurrounding(base);
+}
+
+void ChunkLoader::GenerateSurrounding(const Chunk::Pos &pos) {
 	const Chunk::Pos offset(load_dist, load_dist, load_dist);
-	Generate(base - offset, base + offset);
+	Generate(pos - offset, pos + offset);
 }
 
 void ChunkLoader::Update() {
-	if (!to_generate.empty()) {
-		gen(to_generate.front());
-		loaded.splice(loaded.end(), to_generate, to_generate.begin());
+	if (to_generate.empty()) {
+		return;
+	}
+
+	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;
+		}
 	}
 
-	if (!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);
 }
 
 }