llIntegerToBase64

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Summary

Function: string llIntegerToBase64( integer number );

Returns a string that is a Base64 big endian encode of number

• integer number

Examples

string ASCII7ToString(integer letter)
{
    if(letter >= 0x80 || letter < 0) return "";//Not valid ascii7 character
    return llBase64ToString(llIntegerToBase64(letter << 24));
}
// Packs a 24-bit unsigned integer value (0-16777215) to only 4 Base64 characters.
string Int24ToBase64(integer value)
{
    return llGetSubString(llIntegerToBase64(value<<8), 0, 3);
}
// unpacks a 4-character Base64 value to a 24-bit unsigned integer
integer Base64ToInt24(string value)
{
    return (llBase64ToInteger(value)>>8)&0xffffff; // Masking required to remove sign extension from bit-shifting
}
If you are looking for full Unicode translation, not just ASCII7 see: Combined_Library

Notes

  • Only the first 6 of the 8 characters returned are needed to decoded it back into an integer. The padding "==" can be safely removed for storage.
  • "Big-endian" refers to the fact that the most significant, i.e. highest byte of the integer is processed first: the first characters in the returned Base64 string correspond to this byte, and the last characters correspond to the least significant byte.
    • Combined with bit-shifting, removing characters from the Base64 string allows more efficient packing of small values. See llBase64ToInteger caveats for specifics.

See Also

Deep Notes

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Signature

function string llIntegerToBase64( integer number );