World: factor out Section handling to a generic interface

7 files changed, 246 insertions, 141 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 4e4d23f..2b57fa9 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -15,6 +15,7 @@ add_executable(MinedMap
   World/ChunkData.cpp
   World/Level.cpp
   World/Region.cpp
+  World/Section.cpp
 )
 set_target_properties(MinedMap PROPERTIES COMPILE_FLAGS "-std=c++11 -Wall")
 target_link_libraries(MinedMap ${ZLIB_LIBRARIES} ${PNG_LIBRARIES})
diff --git a/src/World/Block.cpp b/src/World/Block.cpp
index 06017fd..b4a464b 100644
--- a/src/World/Block.cpp
+++ b/src/World/Block.cpp
@@ -26,14 +26,12 @@
 
 #include "Block.hpp"
 #include "../Resource/Biome.hpp"
-#include "../Resource/BlockType.hpp"
 
 
 namespace MinedMap {
 namespace World {
 
 uint32_t Block::getColor() const {
-	const Resource::BlockType *type = Resource::LEGACY_BLOCK_TYPES.types[id][data];
 	if (!type || !type->opaque)
 		return 0;
 
diff --git a/src/World/Block.hpp b/src/World/Block.hpp
index 4975faa..e2dcfde 100644
--- a/src/World/Block.hpp
+++ b/src/World/Block.hpp
@@ -26,28 +26,25 @@
 
 #pragma once
 
-#include <cstdint>
+#include "../NBT/CompoundTag.hpp"
+#include "../Resource/BlockType.hpp"
 
 
 namespace MinedMap {
 namespace World {
 
 struct Block {
-	uint8_t id;
-	uint8_t data;
-
+	const Resource::BlockType *type;
 	unsigned height;
-
 	uint8_t blockLight;
-	uint8_t skyLight;
-
 	uint8_t biome;
 
-	Block() : id(0), data(0), height(0), blockLight(0), skyLight(0), biome(0) {}
-	Block(uint8_t id0, uint8_t data0, unsigned height0, uint8_t blockLight0, uint8_t skyLight0, uint8_t biome0)
-		: id(id0), data(data0), height(height0), blockLight(blockLight0), skyLight(skyLight0), biome(biome0) {}
 
 	uint32_t getColor() const;
+
+	operator bool() const {
+		return type;
+	}
 };
 
 }
diff --git a/src/World/Chunk.cpp b/src/World/Chunk.cpp
index d4c6029..50ac81e 100644
--- a/src/World/Chunk.cpp
+++ b/src/World/Chunk.cpp
@@ -25,14 +25,11 @@
 
 
 #include "Chunk.hpp"
-#include "../Resource/BlockType.hpp"
+#include "../NBT/ListTag.hpp"
+#include "../NBT/StringTag.hpp"
 
-#include <iostream>
-#include <stdexcept>
-#include <cstdlib>
 #include <cstring>
-
-#include <zlib.h>
+#include <stdexcept>
 
 
 namespace MinedMap {
@@ -41,100 +38,77 @@ namespace World {
 Chunk::Chunk(const ChunkData *data) {
 	level = assertValue(data->getRoot().get<NBT::CompoundTag>("Level"));
 
-	std::shared_ptr<const NBT::ByteTag> lightPopulatedTag = level->get<NBT::ByteTag>("LightPopulated");
-	bool lightPopulated = lightPopulatedTag && lightPopulatedTag->getValue();
+	std::shared_ptr<const NBT::ListTag> sectionsTag = level->get<NBT::ListTag>("Sections");
+	if (!sectionsTag)
+		return;
 
-	sections = assertValue(level->get<NBT::ListTag>("Sections"));
-	const NBT::CompoundTag *lastSection = assertValue(dynamic_cast<const NBT::CompoundTag *>(sections->back().get()));
-	maxY = (assertValue(lastSection->get<NBT::ByteTag>("Y"))->getValue() + 1) * SIZE;
+	biomeBytes = level->get<NBT::ByteArrayTag>("Biomes");
+	biomeInts = level->get<NBT::IntArrayTag>("Biomes");
+	assertValue(biomeBytes || biomeInts);
 
-
-	std::shared_ptr<const NBT::ByteArrayTag> biomeTag = assertValue(level->get<NBT::ByteArrayTag>("Biomes"));
-	if (biomeTag->getLength() != SIZE*SIZE)
+	if (biomeBytes && biomeBytes->getLength() != SIZE*SIZE)
+		throw std::invalid_argument("corrupt biome data");
+	else if (biomeInts && biomeInts->getLength() != SIZE*SIZE)
 		throw std::invalid_argument("corrupt biome data");
 
-	biomes = biomeTag->getValue();
-
-	blockIDs.reset(new uint8_t[maxY * SIZE * SIZE]);
-	blockData.reset(new uint8_t[maxY * SIZE * SIZE / 2]);
-	blockSkyLight.reset(new uint8_t[maxY * SIZE * SIZE / 2]);
-	blockBlockLight.reset(new uint8_t[maxY * SIZE * SIZE / 2]);
-
-	std::memset(blockIDs.get(), 0, maxY * SIZE * SIZE);
-	std::memset(blockData.get(), 0, maxY * SIZE * SIZE / 2);
-	std::memset(blockSkyLight.get(), 0xff, maxY * SIZE * SIZE / 2);
-	std::memset(blockBlockLight.get(), 0, maxY * SIZE * SIZE / 2);
-
-
-	for (auto &sectionTag : *sections) {
-		const NBT::CompoundTag *section = assertValue(dynamic_cast<const NBT::CompoundTag *>(sectionTag.get()));
-		std::shared_ptr<const NBT::ByteArrayTag> blocks = assertValue(section->get<NBT::ByteArrayTag>("Blocks"));
-		std::shared_ptr<const NBT::ByteArrayTag> data = assertValue(section->get<NBT::ByteArrayTag>("Data"));
-		size_t Y = assertValue(section->get<NBT::ByteTag>("Y"))->getValue();
-
-		if (blocks->getLength() != SIZE*SIZE*SIZE || data->getLength() != SIZE*SIZE*SIZE/2)
-			throw std::invalid_argument("corrupt chunk data");
-
-		if (lightPopulated) {
-			std::shared_ptr<const NBT::ByteArrayTag> blockLight = assertValue(section->get<NBT::ByteArrayTag>("BlockLight"));
-			std::shared_ptr<const NBT::ByteArrayTag> skyLight = assertValue(section->get<NBT::ByteArrayTag>("SkyLight"));
+	for (auto &sTag : *sectionsTag) {
+		auto s = std::dynamic_pointer_cast<const NBT::CompoundTag>(sTag);
+		std::unique_ptr<Section> section = Section::makeSection(s);
+		size_t Y = section->getY();
+		sections.resize(Y);
+		sections.push_back(std::move(section));
+	}
+}
 
-			if (blockLight->getLength() != SIZE*SIZE*SIZE/2 || skyLight->getLength() != SIZE*SIZE*SIZE/2)
-				throw std::invalid_argument("corrupt chunk data");
+bool Chunk::getBlock(Block *block, const Section *section, size_t x, size_t y, size_t z, uint8_t prev_light) const {
+	if (block->height > 0)
+		return false;
 
-			std::memcpy(blockBlockLight.get() + Y*SIZE*SIZE*SIZE/2, blockLight->getValue(), SIZE*SIZE*SIZE/2);
-			std::memcpy(blockSkyLight.get() + Y*SIZE*SIZE*SIZE/2, skyLight->getValue(), SIZE*SIZE*SIZE/2);
-		}
+	const Resource::BlockType *type = section->getBlockStateAt(x, y, z);
+	if (!type || !type->opaque)
+		return false;
 
-		std::memcpy(blockIDs.get() + Y*SIZE*SIZE*SIZE, blocks->getValue(), SIZE*SIZE*SIZE);
-		std::memcpy(blockData.get() + Y*SIZE*SIZE*SIZE/2, data->getValue(), SIZE*SIZE*SIZE/2);
+	if (!block->type) {
+		block->type = type;
+		block->blockLight = prev_light;
+		block->biome = getBiomeAt(x, z);
 	}
-}
 
-Block Chunk::getBlock(size_t x, size_t y, size_t z) const {
-	size_t y2 = y;
-	if (y2 < maxY-1)
-		y2++;
+	if (type->blue)
+		return false;
 
-	unsigned h;
-	for (h = y; h > 0; h--) {
-		uint8_t id2 = getBlockAt(x, h, z);
-		if (id2 != 8 && id2 != 9)
-			break;
-	}
+	block->height = SIZE*section->getY() + y;
 
-	return Block(
-		getBlockAt(x, y, z),
-		getDataAt(x, y, z),
-		h,
-		getBlockLightAt(x, y2, z),
-		getSkyLightAt(x, y2, z),
-		getBiomeAt(x, z)
-	);
+	return true;
 }
 
 Chunk::Blocks Chunk::getTopLayer() const {
 	size_t done = 0;
-	Blocks ret;
+	Blocks ret = {};
+	uint8_t prev_light[SIZE][SIZE] = {};
 
-	for (ssize_t y = maxY-1; y >= 0; y--) {
+	for (ssize_t Y = sections.size() - 1; Y >= 0; Y--) {
 		if (done == SIZE*SIZE)
 			break;
 
-		for (size_t z = 0; z < SIZE; z++) {
-			for (size_t x = 0; x < SIZE; x++) {
-				if (ret.blocks[x][z].id)
-					continue;
+		if (!sections[Y]) {
+			std::memset(prev_light, 0, sizeof(prev_light));
+			continue;
+		}
+
+		const Section *section = sections[Y].get();
 
-				uint8_t id = getBlockAt(x, y, z);
-				uint8_t data = getDataAt(x, y, z);
+		for (ssize_t y = SIZE-1; y >= 0; y--) {
+			if (done == SIZE*SIZE)
+				break;
 
-				const Resource::BlockType *type = Resource::LEGACY_BLOCK_TYPES.types[id][data];
-				if (!type || !type->opaque)
-					continue;
+			for (size_t z = 0; z < SIZE; z++) {
+				for (size_t x = 0; x < SIZE; x++) {
+					if (getBlock(&ret.blocks[x][z], section, x, y, z, prev_light[x][z]))
+						done++;
 
-				ret.blocks[x][z] = getBlock(x, y, z);
-				done++;
+					prev_light[x][z] = section->getBlockLightAt(x, y, z);
+				}
 			}
 		}
 	}
diff --git a/src/World/Chunk.hpp b/src/World/Chunk.hpp
index 4bd301d..8451cbe 100644
--- a/src/World/Chunk.hpp
+++ b/src/World/Chunk.hpp
@@ -29,13 +29,13 @@
 
 #include "Block.hpp"
 #include "ChunkData.hpp"
-#include "../Util.hpp"
-#include "../NBT/ListTag.hpp"
-#include "../NBT/ByteTag.hpp"
+#include "Section.hpp"
 #include "../NBT/ByteArrayTag.hpp"
+#include "../NBT/IntArrayTag.hpp"
+#include "../Resource/BlockType.hpp"
+#include "../Util.hpp"
 
 #include <cstdint>
-#include <tuple>
 
 
 namespace MinedMap {
@@ -43,62 +43,27 @@ namespace World {
 
 class Chunk {
 public:
-	static const size_t SIZE = 16;
+	static const size_t SIZE = Section::SIZE;
 
 	struct Blocks {
 		Block blocks[SIZE][SIZE];
 	};
 
-
 private:
 	std::shared_ptr<const NBT::CompoundTag> level;
-	std::shared_ptr<const NBT::ListTag> sections;
-
-
-	unsigned maxY;
-
-	std::unique_ptr<uint8_t[]> blockIDs;
-	std::unique_ptr<uint8_t[]> blockData;
-	std::unique_ptr<uint8_t[]> blockSkyLight;
-	std::unique_ptr<uint8_t[]> blockBlockLight;
-	const uint8_t *biomes;
+	std::vector<std::unique_ptr<Section>> sections;
 
+	std::shared_ptr<const NBT::ByteArrayTag> biomeBytes;
+	std::shared_ptr<const NBT::IntArrayTag> biomeInts;
 
-	size_t getIndex(size_t x, size_t y, size_t z) const {
-		if (x >= SIZE || y >= maxY || z >= SIZE)
-			throw std::range_error("Chunk::getIndex(): bad coordinates");
-
-		return SIZE*SIZE*y + SIZE*z + x;
-	}
-
-	uint8_t getHalf(const uint8_t *v, size_t x, size_t y, size_t z) const {
-		size_t i = getIndex(x, y, z);
-
-		if (i % 2)
-			return (v[i/2] >> 4);
+	uint8_t getBiomeAt(size_t x, size_t z) const {
+		if (biomeBytes)
+			return biomeBytes->getValue()[z*SIZE + x];
 		else
-			return (v[i/2] & 0xf);
+			return biomeInts->getValue(z*SIZE + x);
 	}
 
-	uint8_t getBlockAt(size_t x, size_t y, size_t z) const {
-		return blockIDs[getIndex(x, y, z)];
-	}
-
-	uint8_t getDataAt(size_t x, size_t y, size_t z) const {
-		return getHalf(blockData.get(), x, y, z);
-	}
-
-	uint8_t getBlockLightAt(size_t x, size_t y, size_t z) const {
-		return getHalf(blockBlockLight.get(), x, y, z);
-	}
-
-	uint8_t getSkyLightAt(size_t x, size_t y, size_t z) const {
-		return getHalf(blockSkyLight.get(), x, y, z);
-	}
-
-	uint8_t getBiomeAt(size_t x, size_t z) const {
-		return biomes[z*SIZE + x];
-	}
+	bool getBlock(Block *block, const Section *section, size_t x, size_t y, size_t z, uint8_t prev_light) const;
 
 public:
 	Chunk(const ChunkData *data);
@@ -107,11 +72,15 @@ public:
 		return *level;
 	}
 
-	const NBT::ListTag & getSections() const {
-		return *sections;
+	const Resource::BlockType * getBlockStateAt(size_t x, size_t y, size_t z) const {
+		size_t Y = y / SIZE;
+
+		if (Y >= sections.size() || !sections[Y])
+			return nullptr;
+
+		return sections[Y]->getBlockStateAt(x, y % SIZE, z);
 	}
 
-	Block getBlock(size_t x, size_t y, size_t z) const;
 	Blocks getTopLayer() const;
 };
 
diff --git a/src/World/Section.cpp b/src/World/Section.cpp
new file mode 100644
index 0000000..6f06435
--- /dev/null
+++ b/src/World/Section.cpp
@@ -0,0 +1,56 @@
+/*
+  Copyright (c) 2015-2018, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include "Section.hpp"
+#include "../NBT/ByteTag.hpp"
+#include "../Util.hpp"
+
+
+namespace MinedMap {
+namespace World {
+
+Section::Section(const std::shared_ptr<const NBT::CompoundTag> &section) {
+	Y = assertValue(section->get<NBT::ByteTag>("Y"))->getValue();
+	blockLight = section->get<NBT::ByteArrayTag>("BlockLight");
+}
+
+
+std::unique_ptr<Section> Section::makeSection(const std::shared_ptr<const NBT::CompoundTag> &section) {
+	std::shared_ptr<const NBT::ByteArrayTag> blocks = assertValue(section->get<NBT::ByteArrayTag>("Blocks"));
+	std::shared_ptr<const NBT::ByteArrayTag> data = assertValue(section->get<NBT::ByteArrayTag>("Data"));
+
+	return std::unique_ptr<Section>(new LegacySection(section, std::move(blocks), std::move(data)));
+}
+
+const Resource::BlockType * LegacySection::getBlockStateAt(size_t x, size_t y, size_t z) const {
+	uint8_t type = getBlockAt(x, y, z);
+	uint8_t data = getDataAt(x, y, z);
+
+	return Resource::LEGACY_BLOCK_TYPES.types[type][data];
+}
+
+}
+}
diff --git a/src/World/Section.hpp b/src/World/Section.hpp
new file mode 100644
index 0000000..a4686e3
--- /dev/null
+++ b/src/World/Section.hpp
@@ -0,0 +1,110 @@
+/*
+  Copyright (c) 2015-2018, Matthias Schiffer <mschiffer@universe-factory.net>
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+    2. Redistributions in binary form must reproduce the above copyright notice,
+       this list of conditions and the following disclaimer in the documentation
+       and/or other materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+  SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+  OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+  OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#pragma once
+
+
+#include "../NBT/ByteArrayTag.hpp"
+#include "../NBT/CompoundTag.hpp"
+#include "../Resource/BlockType.hpp"
+
+#include <cstdint>
+#include <stdexcept>
+
+
+namespace MinedMap {
+namespace World {
+
+class Section {
+public:
+	static const size_t SIZE = 16;
+
+private:
+	size_t Y;
+	std::shared_ptr<const NBT::ByteArrayTag> blockLight;
+
+protected:
+	static size_t getIndex(size_t x, size_t y, size_t z) {
+		if (x >= SIZE || y >= SIZE || z >= SIZE)
+			throw std::range_error("Chunk::getIndex(): bad coordinates");
+
+		return SIZE*SIZE*y + SIZE*z + x;
+	}
+
+	static uint8_t getHalf(const uint8_t *v, size_t x, size_t y, size_t z) {
+		size_t i = getIndex(x, y, z);
+
+		if (i % 2)
+			return (v[i/2] >> 4);
+		else
+			return (v[i/2] & 0xf);
+	}
+
+	Section(const std::shared_ptr<const NBT::CompoundTag> &section);
+
+public:
+	virtual ~Section() {}
+
+	size_t getY() const { return Y; };
+
+	virtual const Resource::BlockType * getBlockStateAt(size_t x, size_t y, size_t z) const = 0;
+
+	uint8_t getBlockLightAt(size_t x, size_t y, size_t z) const {
+		if (!blockLight)
+			return 0;
+
+		return getHalf(blockLight->getValue(), x, y, z);
+	}
+
+	static std::unique_ptr<Section> makeSection(const std::shared_ptr<const NBT::CompoundTag> &section);
+};
+
+class LegacySection : public Section {
+private:
+	std::shared_ptr<const NBT::ByteArrayTag> blocks;
+	std::shared_ptr<const NBT::ByteArrayTag> data;
+
+
+	uint8_t getBlockAt(size_t x, size_t y, size_t z) const {
+		return blocks->getValue()[getIndex(x, y, z)];
+	}
+
+	uint8_t getDataAt(size_t x, size_t y, size_t z) const {
+		return getHalf(data->getValue(), x, y, z);
+	}
+
+public:
+	LegacySection(
+		const std::shared_ptr<const NBT::CompoundTag> &section,
+		std::shared_ptr<const NBT::ByteArrayTag> &&blocks0,
+		std::shared_ptr<const NBT::ByteArrayTag> &&data0
+	) : Section(section), blocks(blocks0), data(data0) {}
+
+	virtual const Resource::BlockType * getBlockStateAt(size_t x, size_t y, size_t z) const;
+};
+
+}
+}