Difference between revisions of "LlIntegerToBase64"
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If you are looking for full Unicode translation, not just ASCII7 see: Combined_Library
Frionil Fang (talk | contribs) (one more expansion to make it clearer) |
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| Line 8: | Line 8: | ||
|caveats | |caveats | ||
|constants | |constants | ||
|examples=< | |examples=<syntaxhighlight lang="lsl2">string ASCII7ToString(integer letter) | ||
{ | { | ||
if(letter >= 0x80 || letter < 0) return "";//Not valid ascii7 character | if(letter >= 0x80 || letter < 0) return "";//Not valid ascii7 character | ||
return llBase64ToString(llIntegerToBase64(letter << 24)); | return llBase64ToString(llIntegerToBase64(letter << 24)); | ||
}</ | }</syntaxhighlight> | ||
If you are looking for full Unicode translation, not just ASCII7 see: [[Combined_Library#Unicode_Integer_to_UTF8]] | <syntaxhighlight lang="lsl2">// 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 | |||
} | |||
</syntaxhighlight> | |||
If you are looking for full Unicode translation, not just ASCII7 see: [[Combined_Library#Unicode_Integer_to_UTF8|Combined_Library]] | |||
|helpers | |helpers | ||
|also_functions= | |also_functions= | ||
| Line 22: | Line 33: | ||
|also_tests | |also_tests | ||
|also_articles | |also_articles | ||
|notes=Only the first 6 of the 8 characters returned are needed to decoded it back into an integer. | |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|llBase64ToInteger caveats]] for specifics. | |||
|cat1=Base64 | |cat1=Base64 | ||
|cat2=Encoding | |cat2=Encoding | ||
Latest revision as of 10:37, 11 October 2023
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Summary
Function: string llIntegerToBase64( integer number );| 0.0 | Forced Delay |
| 10.0 | Energy |
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
}
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
Functions
| • | llBase64ToInteger | |||
| • | llBase64ToString | |||
| • | llStringToBase64 |
Deep Notes
Signature |
|---|
function string llIntegerToBase64( integer number ); |