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diff --git a/info/blueshift.texinfo b/info/blueshift.texinfo index 4cf1ac6..24f0f33 100644 --- a/info/blueshift.texinfo +++ b/info/blueshift.texinfo @@ -1849,6 +1849,22 @@ Approximate average colour temperature of a clear blue poleward sky. @c https://en.wikipedia.org/wiki/Colour_temperature @end table +The functions @code{temperature} (@code{rgb_temperature}) +and @code{cie_temperature} allow you to, instead of specifing +a colour temperature using literals or these constants, +use the proper name of this constants. For example, +if you use the string `@code{xenon short-arc lamp}' +as the first argument (the temperature value) for the +function @code{temperature}, @code{K_XENON_SHORT_ARC_LAMP} +(6200 kelvins) will be used. These functions utilise +the function @code{kelvins} that does this resolution. +@code{kelvins} kelvins takes either a numerical value +an returns it or takes a string and resolves it. +Predefined recognised punctuation (dot and hyphen) +and regular blank space is converted into underscores, +than the string it converted to upper case and prefixed +with `@code{K_}'. The string is then evaluated without +any sanity-checks, it should match one of the constants. @node Configuration examples |