Start analyzing the chunks

src/Util.hpp

@@ -0,0 +1,42 @@
+/*
+  Copyright (c) 2015, 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 <stdexcept>
+#include <utility>
+
+
+namespace MinedMap {
+
+template <typename T> static inline T assertValue(T&& val) {
+	if (!val)
+		throw std::invalid_argument("assertValue failed");
+
+	return std::forward<T>(val);
+}
+
+}

src/World/Chunk.cpp

@@ -25,6 +25,8 @@
 
 
 #include "Chunk.hpp"
+#include "../Util.hpp"
+#include "../NBT/ByteTag.hpp"
 
 #include <iostream>
 #include <stdexcept>
@@ -36,7 +38,7 @@
 namespace MinedMap {
 namespace World {
 
-std::pair<UniqueCPtr<uint8_t[]>, size_t> Chunk::inflateChunk(uint8_t *data, size_t len) {
+void Chunk::inflateChunk(uint8_t *buffer, size_t buflen) {
 	size_t outlen = 0;
 	uint8_t *output = nullptr;
 
@@ -45,8 +47,8 @@ std::pair<UniqueCPtr<uint8_t[]>, size_t> Chunk::inflateChunk(uint8_t *data, size
 	if (ret != Z_OK)
 		throw std::runtime_error("inflateInit() failed");
 
-	stream.next_in = data;
+	stream.next_in = buffer;
-	stream.avail_in = len;
+	stream.avail_in = buflen;
 
 	while (stream.avail_in) {
 		outlen += 65536;
@@ -67,7 +69,28 @@ std::pair<UniqueCPtr<uint8_t[]>, size_t> Chunk::inflateChunk(uint8_t *data, size
 
 	inflateEnd(&stream);
 
-	return std::make_pair(UniqueCPtr<uint8_t[]>(output), stream.total_out);
+	len = stream.total_out;
+	data = UniqueCPtr<uint8_t[]>(output);
+}
+
+void Chunk::parseChunk() {
+	Buffer nbt(data.get(), len);
+	std::pair<std::string, std::shared_ptr<const NBT::Tag>> tag = NBT::Tag::readNamedTag(&nbt);
+
+	std::shared_ptr<const NBT::CompoundTag>::operator=(std::dynamic_pointer_cast<const NBT::CompoundTag>(tag.second));
+
+	if (!(*this) || tag.first != "")
+		throw std::invalid_argument("invalid root tag");
+
+	sections = (*this)->get<const NBT::ListTag<NBT::CompoundTag>>("Level", "Sections");
+	if (!sections)
+		throw std::invalid_argument("no sections found");
+}
+
+void Chunk::analyzeChunk() {
+	maxY = (assertValue(sections->back()->get<NBT::ByteTag>("Y"))->getValue() + 1) * SIZE;
+
+	std::cerr << "maxY: " << maxY << std::endl;
 }
 
 Chunk::Chunk(uint8_t *buffer, size_t buflen) {
@@ -82,22 +105,9 @@ Chunk::Chunk(uint8_t *buffer, size_t buflen) {
 	if (format != 2)
 		throw std::invalid_argument("unknown chunk format");
 
-	size_t len;
+	inflateChunk(buffer+5, size-1);
-	std::tie(data, len) = inflateChunk(buffer+5, size-1);
+	parseChunk();
-
+	analyzeChunk();
-	std::cerr << "Chunk has size " << size << " (" << len << " inflated)" << std::endl;
-
-	Buffer nbt(data.get(), len);
-	std::pair<std::string, std::shared_ptr<const NBT::Tag>> tag = NBT::Tag::readNamedTag(&nbt);
-
-	std::shared_ptr<const NBT::CompoundTag>::operator=(std::dynamic_pointer_cast<const NBT::CompoundTag>(tag.second));
-
-	if (!(*this) || tag.first != "")
-		throw std::invalid_argument("invalid root tag");
-
-	sections = (*this)->get<const NBT::ListTag<NBT::CompoundTag>>("Level", "Sections");
-	if (!sections)
-		throw std::invalid_argument("no sections found");
 }
 
 }

src/World/Chunk.hpp

@@ -43,9 +43,14 @@ public:
 	static const size_t SIZE = 16;
 
 private:
+	size_t len;
 	UniqueCPtr<uint8_t[]> data;
 
-	static std::pair<UniqueCPtr<uint8_t[]>, size_t> inflateChunk(uint8_t *data, size_t len);
+	unsigned maxY;
+
+	void inflateChunk(uint8_t *data, size_t len);
+	void parseChunk();
+	void analyzeChunk();
 
 	std::shared_ptr<const NBT::ListTag<NBT::CompoundTag>> sections;
 

src/World/Region.cpp

@@ -88,13 +88,12 @@ Region::Region(const char *filename) {
 
 		chunks[x][z].reset(new Chunk(buffer, len * 4096));
 
-		std::cerr << "Read chunk (" << x << "," << z << ") of length " << len << std::endl;
-
 		i += len;
 		c++;
 	}
 
-	std::cerr << "Read " << c <<" of " << chunkMap.size() << " chunks" << std::endl;
+	if (c != chunkMap.size())
+		throw std::invalid_argument("region incomplete");
 }
 
 }