Various types of specialized compression routines. More...

#include <LSCMisc.h>

Public Types
typedef CVectorPoD< LSUINT8, LSUINT32, 1048576UL >	LSC_BUFFER
Static Public Member Functions
static LSBOOL LSE_CALL	CompressNormals (const CVector3 *_pvIn, LSUINT32 _ui32Total, CVectorPoD< CVector2, LSUINT32 > &_vOut, lsc::CBitStream &_bsSigns)
static LSVOID LSE_CALL	DecompressNormals (const CVector2 _pvNormal2d, const lsc::CBitStream &_bsSigns, LSUINT32 _ui32Total, CVector3 _pvOut)
static LSBOOL LSE_CALL	Compress (const LSUINT8 *_pui8Input, LSUINT32 _ui32Length, LSUINT32 _ui32Bits, lsc::CBitStream &_bsStream, LSUINT32 _ui32MaxSize=~0UL)
static LSBOOL LSE_CALL	CompressBest (const LSUINT8 *_pui8Input, LSUINT32 _ui32Length, LSUINT32 &_ui32Bits, lsc::CBitStream &_bsStream)
static LSBOOL LSE_CALL	CompressToBuffer (const LSUINT8 *_pui8Input, LSUINT32 _ui32Length, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	DecompressToBuffer (const LSVOID *_pvData, LSUINTPTR _uiptrSize, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	DecompressToBuffer (const lsstd::IStream &_isStream, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	CompressIndices (const LSUINT32 *_pui32Input, LSUINT32 _ui32Length, lsc::CBitStream &_bsStream)
static LSBOOL LSE_CALL	DecompressIndices (const lsc::CBitStream &_bsStream, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	CompressIndicesToBuffer (const LSUINT32 *_pui32Input, LSUINT32 _ui32Length, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	DecompressIndicesToBuffer (const LSVOID *_pvData, LSUINTPTR _uiptrSize, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	DecompressIndicesToBuffer (const lsstd::IStream &_isStream, LSC_BUFFER &_bBuffer)
Static Protected Member Functions
static LSBOOL LSE_CALL	WriteBytes (const LSUINT8 *_pui8Bytes, LSUINT32 _ui32Length, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	WriteUChar (LSUINT8 _ui8Val, LSC_BUFFER &_bBuffer)
static LSBOOL LSE_CALL	WriteUInt (LSUINT32 _ui32Val, LSC_BUFFER &_bBuffer)
static LSUINT32 LSE_CALL	GetBitsNeededForSignedValue (LSINT32 _i32Value)
static LSINT32 LSE_CALL	GetSignedValue (const lsc::CBitStream &_bsStream, LSUINT32 _ui32Bits)

Detailed Description

Various types of specialized compression routines.

Class CMisc Description: Various types of specialized compression routines. Data often gets compressed better when routines are specialized towards that type of data. For example, if a normal is assumed to be unit-length, only 65 bits are needed to hold it, instead of 96. An array of index data usually starts with low numbers and gradually builds into higher numbers. Only a few bits of data are needed to hold the first several numbers.

Member Typedef Documentation

typedef CVectorPoD<LSUINT8, LSUINT32, 1048576UL> lsc::CMisc::LSC_BUFFER

A buffer used to hold compressed data. It is simply a vector of bytes.

Member Function Documentation

static LSBOOL LSE_CALL lsc::CMisc::Compress	(	const LSUINT8 *	_pui8Input,
		LSUINT32	_ui32Length,
		LSUINT32	_ui32Bits,
		lsc::CBitStream &	_bsStream,
		LSUINT32	_ui32MaxSize = `~0UL`
	)		`[static]`

Compress data at a given bit depth.

Parameters:

_pui8Input	The input data to compress.
_ui32Length	Length of the input data to compress.
_ui32Bits	The maximum bit depth.
_bsStream	The compressed data.
_ui32MaxSize	The maximum size of the compressed data. If the compression size exceeds this, compression is stopped and false is returned.

Returns:: Returns true if there was enough memory to perform the encoding.

static LSBOOL LSE_CALL lsc::CMisc::CompressBest	(	const LSUINT8 *	_pui8Input,
		LSUINT32	_ui32Length,
		LSUINT32 &	_ui32Bits,
		lsc::CBitStream &	_bsStream
	)		`[static]`

Find the best compression size and return the compressed bytes and the bit-count.

Parameters:

_pui8Input	The input data to compress.
_ui32Length	Length of the input data to compress.
_ui32Bits	The returned bit depth.
_bsStream	The compressed data.

Returns:: Returns true if a suitable compression was found, false otherwise.

static LSBOOL LSE_CALL lsc::CMisc::CompressIndices	(	const LSUINT32 *	_pui32Input,
		LSUINT32	_ui32Length,
		lsc::CBitStream &	_bsStream
	)		`[static]`

Compress index data to a given bitsream.

Parameters:

_pui32Input	The input data to compress.
_ui32Length	Number of indices to to which _pui32Input points.
_bsStream	The compressed data.

Returns:: Returns true if there was enough memory to perform the encoding.

static LSBOOL LSE_CALL lsc::CMisc::CompressIndicesToBuffer	(	const LSUINT32 *	_pui32Input,
		LSUINT32	_ui32Length,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Compress index data to a buffer. If the compression is larger than the original data, the original data is written instead.

Parameters:

_pui32Input	The input data to compress.
_ui32Length	Number of indices to to which _pui32Input points.
_bBuffer	The buffer to which to write the bytes.
Returns	true only if all bytes are written to the given buffer.

static LSBOOL LSE_CALL lsc::CMisc::CompressNormals	(	const CVector3 *	_pvIn,
		LSUINT32	_ui32Total,
		CVectorPoD< CVector2, LSUINT32 > &	_vOut,
		lsc::CBitStream &	_bsSigns
	)		`[static]`

Compress an array of normals. The normals are assumed to be of unit length. Works by removing the entire Z component except for its sign, which is returned separately. Normals are reconstructed by determining the Z value that makes the normal unit-length again.

Parameters:

_pvIn	The input 3D vector.
_ui32Total	The number of vectors to which _pvIn points.
_vOut	The output 2D vector containing the X and Y components of the input vector.
_bsSigns	The output sign array. Each bit represents one Z sign.

Returns:: Returns true if there are no memory problems during the compression.

static LSBOOL LSE_CALL lsc::CMisc::CompressToBuffer	(	const LSUINT8 *	_pui8Input,
		LSUINT32	_ui32Length,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Compress bytes to a buffer. If the compression is larger than the original data, the original data is written instead.

Parameters:

_pui8Input	The input data to compress.
_ui32Length	Length of the input data to compress.
_bBuffer	The buffer to which to write the bytes.
Returns	true only if all bytes are written to the given buffer.

static LSBOOL LSE_CALL lsc::CMisc::DecompressIndices	(	const lsc::CBitStream &	_bsStream,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Decompress indices that are not further compressed to a buffer. Input data must have been created with a call to CompressIndices()

Parameters:

_bsStream	The data to decompress.
_bBuffer	Holds the expanded data.

Returns:: Returns true if the input is valid and if there is enough memory to perform the expansion. False is returned otherwise.

static LSBOOL LSE_CALL lsc::CMisc::DecompressIndicesToBuffer	(	const LSVOID *	_pvData,
		LSUINTPTR	_uiptrSize,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Decompress indices from packed data to a buffer.

Parameters:

_pvData	Pointer to the data to expand.
_uiptrSize	Size of the data to expand in bytes.
_bBuffer	Holds the expanded data in which every index is 32 bits.

Returns:: Returns true if the input is valid and if there is enough memory to perform the expansion. False is returned otherwise.

static LSBOOL LSE_CALL lsc::CMisc::DecompressIndicesToBuffer	(	const lsstd::IStream &	_isStream,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Decompress indices from packed data to a buffer.

Parameters:

_isStream	The data to decompress.
_bBuffer	Holds the expanded data in which every index is 32 bits.

Returns:: Returns true if the input is valid and if there is enough memory to perform the expansion. False is returned otherwise.

static LSVOID LSE_CALL lsc::CMisc::DecompressNormals	(	const CVector2 *	_pvNormal2d,
		const lsc::CBitStream &	_bsSigns,
		LSUINT32	_ui32Total,
		CVector3 *	_pvOut
	)		`[static]`

Decompress normals to a buffer that is of the correct length to hold all of the decompressed normals.

Parameters:

_pvNormal2d	An array of 2D normals containing the X and Y components of the expanded 3D normal.
_bsSigns	The array of Z signs. 1 bit per sign.
_ui32Total	The number of normals to which _pvNormal2d points.
_pvOut	The output buffer. Must be allocated to hold _ui32Total 3D normals.

static LSBOOL LSE_CALL lsc::CMisc::DecompressToBuffer	(	const LSVOID *	_pvData,
		LSUINTPTR	_uiptrSize,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Decompress from packed data of any kind to a buffer. If the expanded size is known beforehand, call Allocate() on the buffer to improve the performance of this call.

Parameters:

_pvData	Pointer to the data to expand.
_uiptrSize	Size of the data to expand in bytes.
_bBuffer	Holds the expanded data.

Returns:: Returns true if the input is valid and if there is enough memory to perform the expansion. False is returned otherwise.

static LSBOOL LSE_CALL lsc::CMisc::DecompressToBuffer	(	const lsstd::IStream &	_isStream,
		LSC_BUFFER &	_bBuffer
	)		`[static]`

Decompress from packed data of any kind to a buffer. If the expanded size is known beforehand, call Allocate() on the buffer to improve the performance of this call.

Parameters:

_isStream	Stream containing the bytes to expand.
_bBuffer	Holds the expanded data.

Returns:: Returns true if the input is valid and if there is enough memory to perform the expansion. False is returned otherwise.

static LSUINT32 LSE_CALL lsc::CMisc::GetBitsNeededForSignedValue ( LSINT32 _i32Value ) [static, protected]

Get the number of bits needed to store a number assumed to be signed.

Parameters:

_i32Value The value to count how many bits are needed to store assuming the top bit is reserved for signs.

Returns:: Returns the number of bits needed to store a number assumed to be signed.

static LSINT32 LSE_CALL lsc::CMisc::GetSignedValue	(	const lsc::CBitStream &	_bsStream,
		LSUINT32	_ui32Bits
	)		`[static, protected]`

Get a signed number from a stream.

Parameters:

_bsStream	Stream from which to get the signed value.
_ui32Bits	Number of bits used to store the value.

Returns:: Returns the signed value.

static LSBOOL LSE_CALL lsc::CMisc::WriteBytes	(	const LSUINT8 *	_pui8Bytes,
		LSUINT32	_ui32Length,
		LSC_BUFFER &	_bBuffer
	)		`[static, protected]`

Write bytes to a buffer.

Parameters:

_pui8Bytes	The values to write to the buffer.
_ui32Length	Number of bytes to write to the buffer.
_bBuffer	The buffer to which to write the bytes.
Returns	true only if all bytes are written to the given buffer.

static LSBOOL LSE_CALL lsc::CMisc::WriteUChar	(	LSUINT8	_ui8Val,
		LSC_BUFFER &	_bBuffer
	)		`[static, protected]`

Write a byte to a buffer.

Parameters:

_ui8Val	The value to write to the buffer.
_bBuffer	The buffer to which to write the value.
Returns	true only if all bytes are written to the given buffer.

static LSBOOL LSE_CALL lsc::CMisc::WriteUInt	(	LSUINT32	_ui32Val,
		LSC_BUFFER &	_bBuffer
	)		`[static, protected]`

Write an unsigned integer to a buffer.

Parameters:

_ui32Val	The value to write to the file.
_bBuffer	The buffer to which to write the value.
Returns	true only if all bytes are written to the given buffer.

The documentation for this class was generated from the following file:

F:/My Projects/LSEngine/Modules/LSCompressionLib/Src/Misc/LSCMisc.h

lsc::CMisc Class Reference

Public Types

Static Public Member Functions

Static Protected Member Functions

Detailed Description

Member Typedef Documentation

Member Function Documentation