Mezzanine::Unicode Namespace Reference

A dumping ground for any feature that only relates to unicode work. More...

Functions
String	AsBitString (Int32 IntToPrint)
	A helper function that produces a human readable sequence of ' ', '1' and '0' characters. More...
Int32	GetCharacterFromInt (char *Destination, Int32 BytesUsable, Int32 ByteSequence)
	Convert a number that represents any valid unicode value into its UTF8 representation. More...
Int32	GetIntFromCharacter (Int32 &BytesUsed, const char *CurrentCharacter)
	Get a number suitable for using in an index from a character string. More...

Variables
const UInt8	High1Bit = (1<<7)
	1xxxxxxx - Is used compared against high 2 bits to determine if in middle of byte
const UInt32	High1bytes = 0xFF000000
	The Highest byte of an integer on this system.
const UInt8	High2Bit = High1Bit | (1<<6)
	11xxxxxx
const UInt32	High2bytes = 0xFFFF0000
	The Highest 2 bytes of an integer on this system.
const UInt8	High3Bit = High2Bit | (1<<5)
	111xxxxx
const UInt32	High3bytes = 0xFFFFFF00
	The Highest 3 bytes of an integer on this system.
const UInt8	High4Bit = High3Bit | (1<<4)
	1111xxxx
const UInt8	High5Bit = High4Bit | (1<<3)
	11111xxx
const UInt8	High6Bit = High5Bit | (1<<2)
	111111xx
const UInt8	High7Bit = High6Bit | (1<<1)
	1111111x
const UInt8	High8Bit = High7Bit | 1
	11111111
const UInt8	IterableHighBits [] = {0, High1Bit, High2Bit, High3Bit, High4Bit, High5Bit, High6Bit, High7Bit, High8Bit}
	The index of this array corresponds to the amount of high bits that are set.
const UInt8	IterableLowBits [] = {0, Low1Bit, Low2Bit, Low3Bit, Low4Bit, Low5Bit, Low6Bit, Low7Bit, Low8Bit}
	The index of this array corresponds to the amount of low bits that are set.
const UInt8	Low1Bit = (1)
	xxxxxxx1
const UInt8	Low2Bit = Low1Bit | (1<<1)
	xxxxxx11
const UInt8	Low3Bit = Low2Bit | (1<<2)
	xxxxx111
const UInt8	Low4Bit = Low3Bit | (1<<3)
	xxxx1111
const UInt8	Low5Bit = Low4Bit | (1<<4)
	xxx11111
const UInt8	Low6Bit = Low5Bit | (1<<5)
	xx111111
const UInt8	Low7Bit = Low6Bit | (1<<6)
	x1111111
const UInt8	Low8Bit = Low7Bit | (1<<7)
	11111111
const Int32	UTF8ByteRange1Max = 127
	The maximum Unicode codepoint that can fit into a single UTF8 byte. Equal to 2^7-1.
const Int32	UTF8ByteRange2Max = 4097
	The maximum Unicode codepoint that can fit into 2 UTF8 bytes. Equal to 2^11-1.
const Int32	UTF8ByteRange3Max = 65535
	The maximum Unicode codepoint that can fit into 3 UTF8 bytes. Equal to 2^16-1.
const Int32	UTF8ByteRange4Max = 2097151
	The maximum Unicode codepoint that can fit into 4 UTF8 bytes. Equal to 2^21-1.
const UInt32	UTF8Null2ByteBase = 49280
	This is the numerical representation 0 in a two UTF8 Sequence. Is equal to 11000000 10000000.
const UInt32	UTF8Null3ByteBase = 14712960
	This is the numerical representation 0 in a three UTF8 Sequence. Is equal to 11100000 10000000 10000000.
const UInt32	UTF8Null4ByteBase = 4034953344
	This is the numerical representation 0 in a four UTF8 Sequence. Is equal to 11110000 10000000 10000000 10000000.

Detailed Description

A dumping ground for any feature that only relates to unicode work.

Unicode is a series of numbers that correlate to glyphs. These numbers are seperate from any binary representation. Common binary represenations of the numbers are UTF8, UTF16, and UTF32. This library supports UTF8, which uses between 1 and 4 bytes to represent and valid Unicode glyph. The tools provided here allow conversion between The raw Unicode value, which is useful for algorithms, and its UTF8 representation, which is useful for storage and transmission.

Function Documentation

String Mezzanine::Unicode::AsBitString

(

Int32

IntToPrint)

A helper function that produces a human readable sequence of ' ', '1' and '0' characters.

Parameters

IntToPrint

A 32 bit integer that will be used to create the sequence.

Returns

A Mezzanine::String containing '1' and '0' characters with a space every eight digits.

Definition at line 71 of file unicode.cpp.

Int32 Mezzanine::Unicode::GetCharacterFromInt	(	char *	Destination,
		Int32	BytesUsable,
		Int32	ByteSequence
	)

Convert a number that represents any valid unicode value into its UTF8 representation.

Parameters

Destination	The place to write the results. Never more than 4 bytes will be written. Null terminators are not written.
BytesUsable	How many byte of the Destination are usable.
ByteSequence	The integer value to convert to a UTF8 unicode representation. This sequence must be representable in 21 or fewer bits(<4194304) to be valid.

Returns

The amount of bytes written to destination or -1 on error. This will never be more than 4,

Definition at line 116 of file unicode.cpp.

Int32 Mezzanine::Unicode::GetIntFromCharacter	(	Int32 &	BytesUsed,
		const char *	CurrentCharacter
	)

Get a number suitable for using in an index from a character string.

Parameters

BytesUsed	The value of this variable is ignored and overwritten with the amount of bytes consumed from CurrentCharacter.
CurrentCharacter	a pointer to a c style string.

Returns

If the character pointer to is the beginning of a valid UTF8 character a number suitable for using in an index is returned, otherwise some negative value is returned.

Definition at line 86 of file unicode.cpp.