From e6348ac5a203970c914ab80e94ca1166cf66475d Mon Sep 17 00:00:00 2001
From: Roman Shishkin <spark@uwtech.org>
Date: Thu, 16 May 2019 20:16:27 +0300
Subject: [PATCH] Ignore chunks without sections

---
 src/World/Chunk.cpp | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/World/Chunk.cpp b/src/World/Chunk.cpp
index 7af7923..f94c763 100644
--- a/src/World/Chunk.cpp
+++ b/src/World/Chunk.cpp
@@ -43,15 +43,6 @@ Chunk::Chunk(const ChunkData *data) {
 	if (!sectionsTag)
 		return;
 
-	biomeBytes = level->get<NBT::ByteArrayTag>("Biomes");
-	biomeInts = level->get<NBT::IntArrayTag>("Biomes");
-	assertValue(biomeBytes || biomeInts);
-
-	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");
-
 	for (auto &sTag : *sectionsTag) {
 		auto s = std::dynamic_pointer_cast<const NBT::CompoundTag>(sTag);
 		std::unique_ptr<Section> section = Section::makeSection(s);
@@ -61,6 +52,17 @@ Chunk::Chunk(const ChunkData *data) {
             sections.push_back(std::move(section));
 		}
 	}
+
+	if (!sections.empty()) {
+		biomeBytes = level->get<NBT::ByteArrayTag>("Biomes");
+		biomeInts = level->get<NBT::IntArrayTag>("Biomes");
+		assertValue(biomeBytes || biomeInts);
+
+		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");
+	}
 }
 
 bool Chunk::getBlock(Block *block, const Section *section, size_t x, size_t y, size_t z, uint8_t prev_light) const {