BitExtract: Difference between revisions
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(Created page with "{{Server client function}} {{Needs_Example}} __NOTOC__ {{New feature/item|3.0132|1.3.2|5340| This function returns the unsigned number formed by the bits field to field + width -...") |
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{{ | {{Shared function}} | ||
__NOTOC__ | __NOTOC__ | ||
{{New feature/item|3.0132|1.3.2|5340| | {{New feature/item|3.0132|1.3.2|5340| | ||
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==Syntax== | ==Syntax== | ||
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> | ||
uint bitExtract ( uint var, int field, | uint bitExtract ( uint var, int field [, int width = 1 ] ) | ||
</syntaxhighlight> | </syntaxhighlight> | ||
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==Example== | ==Example== | ||
<syntaxhighlight lang="lua"> | <syntaxhighlight lang="lua"> | ||
function getColorAlpha(color) | |||
return bitExtract(color,24,8) -- return bits 24-32 ( the alpha, http://en.wikipedia.org/wiki/RGBA_color_space ) | |||
end | |||
</syntaxhighlight> | </syntaxhighlight> | ||
==See Also== | ==See Also== | ||
{{Bit_functions}} | {{Bit_functions}} | ||
Latest revision as of 12:35, 20 September 2021
This function returns the unsigned number formed by the bits field to field + width - 1 (range: 0-31).
Syntax
uint bitExtract ( uint var, int field [, int width = 1 ] )
Required arguments
- var: The value
- field: The field number
- width: Number of bits to extract
Returns
Returns the extracted value/bit sequence.
Example
function getColorAlpha(color) return bitExtract(color,24,8) -- return bits 24-32 ( the alpha, http://en.wikipedia.org/wiki/RGBA_color_space ) end