godot_voxel/streams/voxel_block_serializer.cpp

416 lines
14 KiB
C++

#include "voxel_block_serializer.h"
#include "../math/vector3i.h"
#include "../storage/voxel_buffer.h"
#include "../storage/voxel_memory_pool.h"
#include "../thirdparty/lz4/lz4.h"
#include "../util/macros.h"
#include "../util/profiling.h"
#include <core/io/marshalls.h>
#include <core/io/stream_peer.h>
//#include <core/map.h>
#include <core/os/file_access.h>
namespace {
// TODO Introduce versionning
//const uint16_t BLOCK_VERSION = 0;
//const unsigned int BLOCK_VERSION_HEADER_SIZE = sizeof(uint16_t);
const unsigned int BLOCK_TRAILING_MAGIC = 0x900df00d;
const unsigned int BLOCK_TRAILING_MAGIC_SIZE = 4;
const unsigned int BLOCK_METADATA_HEADER_SIZE = sizeof(uint32_t);
} // namespace
size_t get_metadata_size_in_bytes(const VoxelBuffer &buffer) {
size_t size = 0;
const Map<Vector3i, Variant>::Element *elem = buffer.get_voxel_metadata().front();
while (elem != nullptr) {
const Vector3i pos = elem->key();
ERR_FAIL_COND_V_MSG(pos.x < 0 || static_cast<uint32_t>(pos.x) >= VoxelBuffer::MAX_SIZE, 0,
"Invalid voxel metadata X position");
ERR_FAIL_COND_V_MSG(pos.y < 0 || static_cast<uint32_t>(pos.y) >= VoxelBuffer::MAX_SIZE, 0,
"Invalid voxel metadata Y position");
ERR_FAIL_COND_V_MSG(pos.z < 0 || static_cast<uint32_t>(pos.z) >= VoxelBuffer::MAX_SIZE, 0,
"Invalid voxel metadata Z position");
size += 3 * sizeof(uint16_t); // Positions are stored as 3 unsigned shorts
int len;
const Error err = encode_variant(elem->value(), nullptr, len, false);
ERR_FAIL_COND_V_MSG(err != OK, 0, "Error when trying to encode voxel metadata.");
size += len;
elem = elem->next();
}
// If no metadata is found at all, nothing is serialized, not even null.
// It spares 24 bytes (40 if real_t == double),
// and is backward compatible with saves made before introduction of metadata.
if (size != 0 || buffer.get_block_metadata() != Variant()) {
int len;
// Get size first by invoking the function is "length mode"
const Error err = encode_variant(buffer.get_block_metadata(), nullptr, len, false);
ERR_FAIL_COND_V_MSG(err != OK, 0, "Error when trying to encode block metadata.");
size += len;
}
return size;
}
template <typename T>
inline void write(uint8_t *&dst, T d) {
*(T *)dst = d;
dst += sizeof(T);
}
template <typename T>
inline T read(uint8_t *&src) {
T d = *(T *)src;
src += sizeof(T);
return d;
}
// The target buffer MUST have correct size. Recoverable errors must have been checked before.
void serialize_metadata(uint8_t *p_dst, const VoxelBuffer &buffer, const size_t metadata_size) {
uint8_t *dst = p_dst;
{
int written_length;
encode_variant(buffer.get_block_metadata(), dst, written_length, false);
dst += written_length;
// I chose to cast this way to fix a GCC warning.
// If dst - p_dst is negative (which is wrong), it will wrap and cause a justified assertion failure
CRASH_COND_MSG(static_cast<size_t>(dst - p_dst) > metadata_size, "Wrote block metadata out of expected bounds");
}
const Map<Vector3i, Variant>::Element *elem = buffer.get_voxel_metadata().front();
while (elem != nullptr) {
// Serializing key as ushort because it's more than enough for a 3D dense array
static_assert(VoxelBuffer::MAX_SIZE <= 65535, "Maximum size exceeds serialization support");
const Vector3i pos = elem->key();
write<uint16_t>(dst, pos.x);
write<uint16_t>(dst, pos.y);
write<uint16_t>(dst, pos.z);
int written_length;
const Error err = encode_variant(elem->value(), dst, written_length, false);
CRASH_COND_MSG(err != OK, "Error when trying to encode voxel metadata.");
dst += written_length;
CRASH_COND_MSG(static_cast<size_t>(dst - p_dst) > metadata_size, "Wrote voxel metadata out of expected bounds");
elem = elem->next();
}
CRASH_COND_MSG(static_cast<size_t>(dst - p_dst) != metadata_size,
String("Written metadata doesn't match expected count (expected {0}, got {1})")
.format(varray(SIZE_T_TO_VARIANT(metadata_size), (int)(dst - p_dst))));
}
bool deserialize_metadata(uint8_t *p_src, VoxelBuffer &buffer, const size_t metadata_size) {
uint8_t *src = p_src;
size_t remaining_length = metadata_size;
{
Variant block_metadata;
int read_length;
const Error err = decode_variant(block_metadata, src, remaining_length, &read_length, false);
ERR_FAIL_COND_V_MSG(err != OK, false, "Failed to deserialize block metadata");
remaining_length -= read_length;
src += read_length;
CRASH_COND_MSG(remaining_length > metadata_size, "Block metadata size underflow");
buffer.set_block_metadata(block_metadata);
}
while (remaining_length > 0) {
Vector3i pos;
pos.x = read<uint16_t>(src);
pos.y = read<uint16_t>(src);
pos.z = read<uint16_t>(src);
remaining_length -= 3 * sizeof(uint16_t);
Variant metadata;
int read_length;
const Error err = decode_variant(metadata, src, remaining_length, &read_length, false);
ERR_FAIL_COND_V_MSG(err != OK, false, "Failed to deserialize block metadata");
remaining_length -= read_length;
src += read_length;
CRASH_COND_MSG(remaining_length > metadata_size, "Block metadata size underflow");
buffer.set_voxel_metadata(pos, metadata);
}
CRASH_COND_MSG(remaining_length != 0, "Did not read expected size");
return true;
}
size_t get_size_in_bytes(const VoxelBuffer &buffer, size_t &metadata_size) {
size_t size = 0;
const Vector3i size_in_voxels = buffer.get_size();
for (unsigned int channel_index = 0; channel_index < VoxelBuffer::MAX_CHANNELS; ++channel_index) {
const VoxelBuffer::Compression compression = buffer.get_channel_compression(channel_index);
size += 1;
switch (compression) {
case VoxelBuffer::COMPRESSION_NONE: {
size += size_in_voxels.volume() * sizeof(uint8_t);
} break;
case VoxelBuffer::COMPRESSION_UNIFORM: {
size += 1;
} break;
default:
ERR_PRINT("Unhandled compression mode");
CRASH_NOW();
}
}
metadata_size = get_metadata_size_in_bytes(buffer);
size_t metadata_size_with_header = 0;
if (metadata_size > 0) {
metadata_size_with_header = metadata_size + BLOCK_METADATA_HEADER_SIZE;
}
return size + metadata_size_with_header + BLOCK_TRAILING_MAGIC_SIZE;
}
const std::vector<uint8_t> &VoxelBlockSerializerInternal::serialize(VoxelBuffer &voxel_buffer) {
VOXEL_PROFILE_SCOPE();
size_t metadata_size = 0;
const size_t data_size = get_size_in_bytes(voxel_buffer, metadata_size);
_data.resize(data_size);
CRASH_COND(_file_access_memory.open_custom(_data.data(), _data.size()) != OK);
FileAccessMemory *f = &_file_access_memory;
for (unsigned int channel_index = 0; channel_index < VoxelBuffer::MAX_CHANNELS; ++channel_index) {
VoxelBuffer::Compression compression = voxel_buffer.get_channel_compression(channel_index);
f->store_8(static_cast<uint8_t>(compression));
switch (compression) {
case VoxelBuffer::COMPRESSION_NONE: {
ArraySlice<uint8_t> data;
CRASH_COND(!voxel_buffer.get_channel_raw(channel_index, data));
f->store_buffer(data.data(), data.size());
} break;
case VoxelBuffer::COMPRESSION_UNIFORM: {
uint64_t v = voxel_buffer.get_voxel(Vector3i(), channel_index);
switch (voxel_buffer.get_channel_depth(channel_index)) {
case VoxelBuffer::DEPTH_8_BIT:
f->store_8(v);
break;
case VoxelBuffer::DEPTH_16_BIT:
f->store_16(v);
break;
case VoxelBuffer::DEPTH_32_BIT:
f->store_32(v);
break;
case VoxelBuffer::DEPTH_64_BIT:
f->store_64(v);
break;
default:
CRASH_NOW();
}
} break;
default:
CRASH_COND("Unhandled compression mode");
}
}
// Metadata has more reasons to fail. If a recoverable error occurs prior to serializing,
// we just discard all metadata as if it was empty.
if (metadata_size > 0) {
f->store_32(metadata_size);
_metadata_tmp.resize(metadata_size);
// This function brings me joy. </irony>
serialize_metadata(_metadata_tmp.data(), voxel_buffer, metadata_size);
f->store_buffer(_metadata_tmp.data(), _metadata_tmp.size());
}
f->store_32(BLOCK_TRAILING_MAGIC);
return _data;
}
bool VoxelBlockSerializerInternal::deserialize(const std::vector<uint8_t> &p_data, VoxelBuffer &out_voxel_buffer) {
VOXEL_PROFILE_SCOPE();
CRASH_COND(_file_access_memory.open_custom(p_data.data(), p_data.size()) != OK);
FileAccessMemory *f = &_file_access_memory;
for (unsigned int channel_index = 0; channel_index < VoxelBuffer::MAX_CHANNELS; ++channel_index) {
uint8_t compression_value = f->get_8();
ERR_FAIL_COND_V_MSG(compression_value >= VoxelBuffer::COMPRESSION_COUNT, false,
"At offset 0x" + String::num_int64(f->get_position() - 1, 16));
VoxelBuffer::Compression compression = (VoxelBuffer::Compression)compression_value;
switch (compression) {
case VoxelBuffer::COMPRESSION_NONE: {
out_voxel_buffer.decompress_channel(channel_index);
ArraySlice<uint8_t> buffer;
CRASH_COND(!out_voxel_buffer.get_channel_raw(channel_index, buffer));
uint32_t read_len = f->get_buffer(buffer.data(), buffer.size());
if (read_len != buffer.size()) {
ERR_PRINT("Unexpected end of file");
return false;
}
} break;
case VoxelBuffer::COMPRESSION_UNIFORM: {
uint64_t v;
switch (out_voxel_buffer.get_channel_depth(channel_index)) {
case VoxelBuffer::DEPTH_8_BIT:
v = f->get_8();
break;
case VoxelBuffer::DEPTH_16_BIT:
v = f->get_16();
break;
case VoxelBuffer::DEPTH_32_BIT:
v = f->get_32();
break;
case VoxelBuffer::DEPTH_64_BIT:
v = f->get_64();
break;
default:
CRASH_NOW();
}
out_voxel_buffer.clear_channel(channel_index, v);
} break;
default:
ERR_PRINT("Unhandled compression mode");
return false;
}
}
if (p_data.size() - f->get_position() > BLOCK_TRAILING_MAGIC_SIZE) {
size_t metadata_size = f->get_32();
_metadata_tmp.resize(metadata_size);
f->get_buffer(_metadata_tmp.data(), _metadata_tmp.size());
deserialize_metadata(_metadata_tmp.data(), out_voxel_buffer, _metadata_tmp.size());
}
// Failure at this indicates file corruption
ERR_FAIL_COND_V_MSG(f->get_32() != BLOCK_TRAILING_MAGIC, false,
"At offset 0x" + String::num_int64(f->get_position() - 4, 16));
return true;
}
const std::vector<uint8_t> &VoxelBlockSerializerInternal::serialize_and_compress(VoxelBuffer &voxel_buffer) {
VOXEL_PROFILE_SCOPE();
const std::vector<uint8_t> &data = serialize(voxel_buffer);
unsigned int header_size = sizeof(unsigned int);
_compressed_data.resize(header_size + LZ4_compressBound(data.size()));
// Write header
CRASH_COND(_file_access_memory.open_custom(_compressed_data.data(), _compressed_data.size()) != OK);
_file_access_memory.store_32(data.size());
_file_access_memory.close();
int compressed_size = LZ4_compress_default(
(const char *)data.data(),
(char *)_compressed_data.data() + header_size,
data.size(),
_compressed_data.size() - header_size);
CRASH_COND(compressed_size < 0);
CRASH_COND(compressed_size == 0);
_compressed_data.resize(header_size + compressed_size);
return _compressed_data;
}
bool VoxelBlockSerializerInternal::decompress_and_deserialize(const std::vector<uint8_t> &p_data, VoxelBuffer &out_voxel_buffer) {
VOXEL_PROFILE_SCOPE();
// Read header
unsigned int header_size = sizeof(unsigned int);
ERR_FAIL_COND_V(_file_access_memory.open_custom(p_data.data(), p_data.size()) != OK, false);
unsigned int decompressed_size = _file_access_memory.get_32();
_file_access_memory.close();
_data.resize(decompressed_size);
unsigned int actually_decompressed_size = LZ4_decompress_safe(
(const char *)p_data.data() + header_size,
(char *)_data.data(),
p_data.size() - header_size,
_data.size());
ERR_FAIL_COND_V_MSG(actually_decompressed_size < 0, false,
String("LZ4 decompression error {0}").format(varray(actually_decompressed_size)));
ERR_FAIL_COND_V_MSG(actually_decompressed_size != decompressed_size, false,
String("Expected {0} bytes, obtained {1}").format(varray(decompressed_size, actually_decompressed_size)));
return deserialize(_data, out_voxel_buffer);
}
bool VoxelBlockSerializerInternal::decompress_and_deserialize(FileAccess *f, unsigned int size_to_read, VoxelBuffer &out_voxel_buffer) {
VOXEL_PROFILE_SCOPE();
ERR_FAIL_COND_V(f == nullptr, false);
_compressed_data.resize(size_to_read);
unsigned int read_size = f->get_buffer(_compressed_data.data(), size_to_read);
ERR_FAIL_COND_V(read_size != size_to_read, false);
return decompress_and_deserialize(_compressed_data, out_voxel_buffer);
}
int VoxelBlockSerializerInternal::serialize(Ref<StreamPeer> peer, Ref<VoxelBuffer> voxel_buffer, bool compress) {
if (compress) {
const std::vector<uint8_t> &data = serialize_and_compress(**voxel_buffer);
peer->put_data(data.data(), data.size());
return data.size();
} else {
const std::vector<uint8_t> &data = serialize(**voxel_buffer);
peer->put_data(data.data(), data.size());
return data.size();
}
}
void VoxelBlockSerializerInternal::deserialize(Ref<StreamPeer> peer, Ref<VoxelBuffer> voxel_buffer, int size, bool decompress) {
if (decompress) {
_compressed_data.resize(size);
const Error err = peer->get_data(_compressed_data.data(), _compressed_data.size());
ERR_FAIL_COND(err != OK);
bool success = decompress_and_deserialize(_compressed_data, **voxel_buffer);
ERR_FAIL_COND(!success);
} else {
_data.resize(size);
const Error err = peer->get_data(_data.data(), _data.size());
ERR_FAIL_COND(err != OK);
deserialize(_data, **voxel_buffer);
}
}
int VoxelBlockSerializer::serialize(Ref<StreamPeer> peer, Ref<VoxelBuffer> voxel_buffer, bool compress) {
ERR_FAIL_COND_V(voxel_buffer.is_null(), 0);
ERR_FAIL_COND_V(peer.is_null(), 0);
return _serializer.serialize(peer, voxel_buffer, compress);
}
void VoxelBlockSerializer::deserialize(Ref<StreamPeer> peer, Ref<VoxelBuffer> voxel_buffer, int size, bool decompress) {
ERR_FAIL_COND(voxel_buffer.is_null());
ERR_FAIL_COND(peer.is_null());
ERR_FAIL_COND(size <= 0);
_serializer.deserialize(peer, voxel_buffer, size, decompress);
}
void VoxelBlockSerializer::_bind_methods() {
ClassDB::bind_method(D_METHOD("serialize", "peer", "voxel_buffer", "compress"), &VoxelBlockSerializer::serialize);
ClassDB::bind_method(D_METHOD("deserialize", "peer", "voxel_buffer", "size", "decompress"), &VoxelBlockSerializer::deserialize);
}