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< img src = "../logo.png" class = "logo" alt = "" > < h1 > Contrast Text Color< / h1 >
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< small class = "dont-index" > Source: < a href = "https://github.com/agdamsbo/stRoke/blob/HEAD/R/contrast_text.R" class = "external-link" > < code > R/contrast_text.R< / code > < / a > < / small >
< div class = "d-none name" > < code > contrast_text.Rd< / code > < / div >
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< div class = "ref-description section level2" >
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< p > Calculates the best contrast text color for a given
background color.< / p >
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< / div >
< div class = "section level2" >
< h2 id = "ref-usage" > Usage< a class = "anchor" aria-label = "anchor" href = "#ref-usage" > < / a > < / h2 >
< div class = "sourceCode" > < pre class = "sourceCode r" > < code > < span > < span class = "fu" > contrast_text< / span > < span class = "op" > (< / span > < / span >
< span > < span class = "va" > background< / span > ,< / span >
< span > light_text < span class = "op" > =< / span > < span class = "st" > "white"< / span > ,< / span >
< span > dark_text < span class = "op" > =< / span > < span class = "st" > "black"< / span > ,< / span >
< span > threshold < span class = "op" > =< / span > < span class = "fl" > 0.5< / span > ,< / span >
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< span > method < span class = "op" > =< / span > < span class = "st" > "perceived_2"< / span > ,< / span >
< span > < span class = "va" > ...< / span > < / span >
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< span > < span class = "op" > )< / span > < / span > < / code > < / pre > < / div >
< / div >
< div class = "section level2" >
< h2 id = "arguments" > Arguments< a class = "anchor" aria-label = "anchor" href = "#arguments" > < / a > < / h2 >
< dl > < dt > background< / dt >
< dd > < p > A hex/named color value that represents the background.< / p > < / dd >
< dt > light_text< / dt >
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< dd > < p > A hex/named color value that represents the light text
color.< / p > < / dd >
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< dt > dark_text< / dt >
< dd > < p > A hex/named color value that represents the dark text color.< / p > < / dd >
< dt > threshold< / dt >
< dd > < p > A numeric value between 0 and 1 that is used to determine
the luminance threshold of the background color for text color.< / p > < / dd >
< dt > method< / dt >
< dd > < p > A character string that specifies the method for calculating
the luminance. Three different methods are available:
c("relative","perceived","perceived_2")< / p > < / dd >
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< dt > ...< / dt >
< dd > < p > parameter overflow. Ignored.< / p > < / dd >
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< / dl > < / div >
< div class = "section level2" >
< h2 id = "value" > Value< a class = "anchor" aria-label = "anchor" href = "#value" > < / a > < / h2 >
< p > A character string that contains the best contrast text color.< / p >
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< h2 id = "details" > Details< a class = "anchor" aria-label = "anchor" href = "#details" > < / a > < / h2 >
< p > This function aids in deciding the font color to print on a given background.
The function is based on the example provided by teppo:
https://stackoverflow.com/a/66669838/21019325.
The different methods provided are based on the methods outlined in the
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StackOverflow thread:
https://stackoverflow.com/questions/596216/formula-to-determine-perceived-brightness-of-rgb-color< / p >
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< / div >
< div class = "section level2" >
< h2 id = "ref-examples" > Examples< a class = "anchor" aria-label = "anchor" href = "#ref-examples" > < / a > < / h2 >
< div class = "sourceCode" > < pre class = "sourceCode r" > < code > < span class = "r-in" > < span > < span class = "fu" > contrast_text< / span > < span class = "op" > (< / span > < span class = "fu" > < a href = "https://rdrr.io/r/base/c.html" class = "external-link" > c< / a > < / span > < span class = "op" > (< / span > < span class = "st" > "#F2F2F2"< / span > , < span class = "st" > "blue"< / span > < span class = "op" > )< / span > < span class = "op" > )< / span > < / span > < / span >
< span class = "r-out co" > < span class = "r-pr" > #> < / span > [1] "black" "white"< / span >
< span class = "r-in" > < span > < / span > < / span >
< span class = "r-in" > < span > < span class = "fu" > contrast_text< / span > < span class = "op" > (< / span > < span class = "fu" > < a href = "https://rdrr.io/r/base/c.html" class = "external-link" > c< / a > < / span > < span class = "op" > (< / span > < span class = "st" > "#F2F2F2"< / span > , < span class = "st" > "blue"< / span > < span class = "op" > )< / span > , method< span class = "op" > =< / span > < span class = "st" > "relative"< / span > < span class = "op" > )< / span > < / span > < / span >
< span class = "r-out co" > < span class = "r-pr" > #> < / span > [1] "black" "white"< / span >
< / code > < / pre > < / div >
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< p > < / p > < p > Developed by Andreas Gammelgaard Damsbo.< / p >
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