VoxelEngine/src/voxels/compressed_chunks.cpp
2025-01-12 03:05:58 +03:00

62 lines
2.1 KiB
C++

#include "compressed_chunks.hpp"
#include "coders/rle.hpp"
#include "coders/gzip.hpp"
#include "coders/byte_utils.hpp"
#include "voxels/Chunk.hpp"
inline constexpr int HAS_VOXELS = 0x1;
inline constexpr int HAS_METADATA = 0x2;
std::vector<ubyte> compressed_chunks::encode(const Chunk& chunk) {
auto data = chunk.encode();
/// world.get_chunk_data is only available in the main Lua state
static util::Buffer<ubyte> rleBuffer;
if (rleBuffer.size() < CHUNK_DATA_LEN * 2) {
rleBuffer = util::Buffer<ubyte>(CHUNK_DATA_LEN * 2);
}
size_t rleCompressedSize =
extrle::encode16(data.get(), CHUNK_DATA_LEN, rleBuffer.data());
const auto gzipCompressedData = gzip::compress(
rleBuffer.data(), rleCompressedSize
);
auto metadataBytes = chunk.blocksMetadata.serialize();
ByteBuilder builder(2 + 8 + gzipCompressedData.size() + metadataBytes.size());
builder.put(HAS_VOXELS | HAS_METADATA); // flags
builder.put(0); // reserved
builder.putInt32(gzipCompressedData.size());
builder.put(gzipCompressedData.data(), gzipCompressedData.size());
builder.putInt32(metadataBytes.size());
builder.put(metadataBytes.data(), metadataBytes.size());
return builder.build();
}
void compressed_chunks::decode(Chunk& chunk, const ubyte* src, size_t size) {
ByteReader reader(src, size);
ubyte flags = reader.get();
reader.skip(1); // reserved byte
if (flags & HAS_VOXELS) {
size_t gzipCompressedSize = reader.getInt32();
auto rleData = gzip::decompress(reader.pointer(), gzipCompressedSize);
reader.skip(gzipCompressedSize);
/// world.get_chunk_data is only available in the main Lua state
static util::Buffer<ubyte> voxelData (CHUNK_DATA_LEN);
extrle::decode16(rleData.data(), rleData.size(), voxelData.data());
chunk.decode(voxelData.data());
chunk.updateHeights();
}
if (flags & HAS_METADATA) {
size_t metadataSize = reader.getInt32();
chunk.blocksMetadata.deserialize(reader.pointer(), metadataSize);
reader.skip(metadataSize);
}
chunk.setModifiedAndUnsaved();
}