AnotherFoxGuy/polyvox
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Replaced arrays with std::vector.

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This commit is contained in:
Daviw Williams 2013-10-02 16:48:30 +02:00
parent a4e09c2481
commit 498f21f63f
2 changed files with 25 additions and 11 deletions
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5
library/PolyVoxCore/include/PolyVoxCore/MinizBlockCompressor.h
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@ -44,12 +44,17 @@ namespace PolyVox
void decompress(CompressedBlock<VoxelType>* pSrcBlock, UncompressedBlock<VoxelType>* pDstBlock);
private:
uint32_t getExpectedCompressedSize(uint32_t uUncompressedInputSize);
uint32_t getMaxCompressedSize(uint32_t uUncompressedInputSize);
uint32_t compressWithMiniz(const void* pSrcData, uint32_t uSrcLength, void* pDstData, uint32_t uDstLength);
uint32_t decompressWithMiniz(const void* pSrcData, uint32_t uSrcLength, void* pDstData, uint32_t uDstLength);
unsigned int m_uCompressionFlags;
// Data gets compressed into this, then we check how big the result
// is and copy the required number of bytes to the destination block.
std::vector<uint8_t> m_vecTempBuffer;
// tdefl_compressor contains all the state needed by the low-level compressor so it's a pretty big struct (~300k).
tdefl_compressor* m_pDeflator;
};

31
library/PolyVoxCore/include/PolyVoxCore/MinizBlockCompressor.inl
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@ -62,9 +62,11 @@ namespace PolyVox
void* pSrcData = reinterpret_cast<void*>(pSrcBlock->getData());
size_t uSrcLength = pSrcBlock->getDataSizeInBytes();
uint8_t tempBuffer[1000];
uint8_t* pDstData = reinterpret_cast<uint8_t*>( tempBuffer );
size_t uDstLength = 1000;
// This compressor is expected to be used many times to compress a large number of blocks, but they are all
// expected to have the same size. Therefore the resize() function below will only perform allocation once.
m_vecTempBuffer.resize(getExpectedCompressedSize(uSrcLength));
uint8_t* pDstData = &(m_vecTempBuffer[0]);
size_t uDstLength = m_vecTempBuffer.size();
uint32_t uCompressedLength = 0;
@ -82,12 +84,13 @@ namespace PolyVox
// buffer is not big enough. So now we try again using a buffer that is definitely big enough.
// Note that ideally we will choose our earlier buffer size so that this almost never happens.
logWarning() << "The compressor failed to compress the block, probabaly due to the buffer being too small.";
logWarning() << "The compression will be tried again with a larger buffer";
uint32_t uMaxCompressedSize = getMaxCompressedSize(uSrcLength);
uint8_t* buffer = new uint8_t[ uMaxCompressedSize ];
logWarning() << "The compression will be tried again with a larger buffer.";
pDstData = reinterpret_cast<uint8_t*>( buffer );
uDstLength = uMaxCompressedSize;
std::vector<uint8_t> vecExtraBigBuffer;
vecExtraBigBuffer.resize(getMaxCompressedSize(uSrcLength));
uint8_t* pDstData = &(vecExtraBigBuffer[0]);
size_t uDstLength = vecExtraBigBuffer.size();
try
{
@ -101,11 +104,8 @@ namespace PolyVox
{
// At this point it didn't work even with a bigger buffer.
// Not much more we can do so just rethrow the exception.
delete[] buffer;
POLYVOX_THROW(std::runtime_error, "Failed to compress block data");
}
delete[] buffer;
}
}
@ -125,6 +125,15 @@ namespace PolyVox
POLYVOX_THROW_IF(uUncompressedLength != pDstBlock->getDataSizeInBytes(), std::runtime_error, "Decompressed data does not have the expected length");
}
template <typename VoxelType>
uint32_t MinizBlockCompressor<VoxelType>::getExpectedCompressedSize(uint32_t uUncompressedInputSize)
{
// We expect this block compressor will be used for smoothly changing volume data such as density fields and so
// the compression rate might not be great. The value beloew is basically a guess based on previous experience.
uint32_t uExpectedCompressionRate = 4;
return uUncompressedInputSize / uExpectedCompressionRate;
}
template <typename VoxelType>
uint32_t MinizBlockCompressor<VoxelType>::getMaxCompressedSize(uint32_t uUncompressedInputSize)
{