Performance improvements

2 files changed, 72 insertions, 90 deletions

diff --git a/src/World/Chunk.cpp b/src/World/Chunk.cpp
index c3c15f8..5a6f95b 100644
--- a/src/World/Chunk.cpp
+++ b/src/World/Chunk.cpp
@@ -30,6 +30,7 @@
 #include <iostream>
 #include <stdexcept>
 #include <cstdlib>
+#include <cstring>
 
 #include <zlib.h>
 
@@ -101,27 +102,32 @@ void Chunk::analyzeChunk() {
 	if (!lightPopulatedTag && lightPopulatedTag->getValue())
 		throw std::invalid_argument("light data missing");
 
-	for (auto &section : *assertValue(level->get<NBT::ListTag<NBT::CompoundTag>>("Sections")))
-		sections.emplace_back(*section);
+	sections = assertValue(level->get<NBT::ListTag<NBT::CompoundTag>>("Sections"));
+	maxY = (assertValue(sections->back()->get<NBT::ByteTag>("Y"))->getValue() + 1) * SIZE;
 
-	maxY = sections.back().getY() + SIZE;
-	blocks.reset(new Block[maxY * SIZE * SIZE]);
+	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]);
 
-	for (auto &section : sections) {
-		unsigned Y = section.getY();
+	std::memset(blockSkyLight.get(), 0xff, maxY * SIZE * SIZE / 2);
 
-		for (size_t y = 0; y < SIZE; y++) {
-			for (size_t z = 0; z < SIZE; z++) {
-				for (size_t x = 0; x < SIZE; x++) {
-					Block &block = getBlock(x, Y+y, z);
 
-					block.id = section.getBlockAt(x, y, z);
-					block.data = section.getDataAt(x, y, z);
-					block.blockLight = section.getBlockLightAt(x, y, z);
-					block.skyLight = section.getSkyLightAt(x, y, z);
-				}
-			}
-		}
+	for (auto &section : *sections) {
+		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"));
+		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"));
+		size_t Y = assertValue(section->get<NBT::ByteTag>("Y"))->getValue();
+
+		if (blocks->getLength() != SIZE*SIZE*SIZE || data->getLength() != SIZE*SIZE*SIZE/2
+		    || blockLight->getLength() != SIZE*SIZE*SIZE/2 || skyLight->getLength() != SIZE*SIZE*SIZE/2)
+			throw std::invalid_argument("corrupt chunk data");
+
+		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);
+		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);
 	}
 }
 
@@ -138,29 +144,27 @@ Chunk::Blocks Chunk::getTopLayer() const {
 				if (ret.blocks[x][z].id)
 					continue;
 
-				const Block &block = getBlock(x, y, z);
-				if (!BLOCK_TYPES[block.id].opaque)
+				uint8_t id = getBlockAt(x, y, z);
+				if (!BLOCK_TYPES[id].opaque)
 					continue;
 
 				Block &b = ret.blocks[x][z];
 
-				b.id = block.id;
-				b.data = block.data;
+				b.id = id;
+				b.data = getDataAt(x, y, z);
 
-				const Block *lightBlock;
-				if (y < maxY-1)
-					lightBlock = &getBlock(x, y+1, z);
-				else
-					lightBlock =  &block;
+				size_t y2 = y;
+				if (y2 < maxY-1)
+					y2++;
 
-				b.blockLight = lightBlock->blockLight;
-				b.skyLight = lightBlock->skyLight;
+				b.blockLight = getBlockLightAt(x, y2, z);
+				b.skyLight = getSkyLightAt(x, y2, z);
 
 
 				unsigned h;
 				for (h = y; h > 0; h--) {
-					const Block &block2 = getBlock(x, h, z);
-					if (block2.id != 8 && block2.id != 9)
+					uint8_t id2 = getBlockAt(x, h, z);
+					if (id2 != 8 && id2 != 9)
 						break;
 				}
 
diff --git a/src/World/Chunk.hpp b/src/World/Chunk.hpp
index 333d5e5..a4948b7 100644
--- a/src/World/Chunk.hpp
+++ b/src/World/Chunk.hpp
@@ -47,83 +47,61 @@ class Chunk {
 public:
 	static const size_t SIZE = 16;
 
-	class Section {
-	private:
-		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;
-		}
-
-		std::shared_ptr<const NBT::ByteArrayTag> blocks;
-		std::shared_ptr<const NBT::ByteArrayTag> data;
-
-		std::shared_ptr<const NBT::ByteArrayTag> blockLight;
-		std::shared_ptr<const NBT::ByteArrayTag> skyLight;
-
-		unsigned Y;
-
-	public:
-		Section(const NBT::CompoundTag &s) {
-			blocks = assertValue(s.get<NBT::ByteArrayTag>("Blocks"));
-			data = assertValue(s.get<NBT::ByteArrayTag>("Data"));
-			blockLight = assertValue(s.get<NBT::ByteArrayTag>("BlockLight"));
-			skyLight = assertValue(s.get<NBT::ByteArrayTag>("SkyLight"));
-
-			if (blocks->getLength() != SIZE*SIZE*SIZE || data->getLength() != SIZE*SIZE*SIZE/2
-			    || blockLight->getLength() != SIZE*SIZE*SIZE/2 || skyLight->getLength() != SIZE*SIZE*SIZE/2)
-				throw std::invalid_argument("corrupt chunk data");
-
-			Y = assertValue(s.get<NBT::ByteTag>("Y"))->getValue() * SIZE;
-		}
-
-		uint8_t getBlockAt(size_t x, size_t y, size_t z) const {
-			return blocks->get(getIndex(x, y, z));
-		}
-
-		uint8_t getDataAt(size_t x, size_t y, size_t z) const {
-			return data->getHalf(getIndex(x, y, z));
-		}
-
-		uint8_t getBlockLightAt(size_t x, size_t y, size_t z) const {
-			return blockLight->getHalf(getIndex(x, y, z));
-		}
-
-		uint8_t getSkyLightAt(size_t x, size_t y, size_t z) const {
-			return skyLight->getHalf(getIndex(x, y, z));
-		}
-
-		unsigned getY() const {
-			return Y;
-		}
-	};
-
 	struct Blocks {
 		Block blocks[SIZE][SIZE];
 	};
 
+
 private:
 	size_t len;
 	UniqueCPtr<uint8_t[]> data;
 
 	std::shared_ptr<const NBT::CompoundTag> root;
 	std::shared_ptr<const NBT::CompoundTag> level;
+	std::shared_ptr<const NBT::ListTag<NBT::CompoundTag>> sections;
 
-	std::vector<Section> sections;
 
 	unsigned maxY;
 
-	std::unique_ptr<Block[]> blocks;
+	std::unique_ptr<uint8_t[]> blockIDs;
+	std::unique_ptr<uint8_t[]> blockData;
+	std::unique_ptr<uint8_t[]> blockSkyLight;
+	std::unique_ptr<uint8_t[]> blockBlockLight;
+
 
-	Block & getBlock(size_t x, size_t y, size_t z) {
-		return blocks[SIZE*SIZE*y + SIZE*z + x];
+	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;
 	}
 
-	const Block & getBlock(size_t x, size_t y, size_t z) const {
-		return blocks[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);
+		else
+			return (v[i/2] & 0xf);
 	}
 
+	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);
+	}
+
+
 	void inflateChunk(Buffer buffer);
 	void parseChunk();
 	void analyzeChunk();
@@ -135,8 +113,8 @@ public:
 		return *level;
 	}
 
-	const std::vector<Section> & getSections() const {
-		return sections;
+	const NBT::ListTag<NBT::CompoundTag> & getSections() const {
+		return *sections;
 	}
 
 	Blocks getTopLayer() const;