Color Contrast Chart

Compare one or more pages from a simulated Munsell book of soil colors to a reference color.

contrastChart(
  m,
  hues,
  ccAbbreviate = 1,
  style = "hue",
  gridLines = FALSE,
  de00.cex = 0.6,
  cc.cex = 0.6,
  thresh = NULL,
  returnData = FALSE
)

Arguments

m

Munsell representation of a single color for comparison e.g. '10YR 4/3'

hues

vector of one or more Munsell hue pages to display

ccAbbreviate

length of abbreviated contrast classes, use 0 to suppress labels

style

'hue' or 'CC', see details

gridLines

logical, add grid lines to the color contrast chart

de00.cex

character scaling applied to dE00 annotation

cc.cex

character scaling applied to contrast class annotation

thresh

threshold (<) applied to pair-wise comparisons and resulting color chips

returnData

logical, return lattice figure + data used to generate the figure

Details

A simulated Munsell color book page or pages are used to demonstrate color contrast between all chips and the reference color m (highlighted in red). NCSS color contrast class and CIE delta-E00 values are printed below all other color chips. Munsell color chips for chroma 5 and 7 are omitted, but axis labels are retained as a reminder of this fact.

Setting style='hue' emphasizes the contrast classes and CIE delta-E00 of chips adjacent to m. Setting style='CC' emphasizes adjacent chips according to respective contrast class via lattice panels.

Two-way panels are used when multiple hues are provided and style='CC'. The default output can be greatly enhanced via:

latticeExtra::useOuterStrips(..., strip = strip.custom(bg=grey(0.85)), strip.left = strip.custom(bg=grey(0.85)) )

Author

D.E. Beaudette

Examples

# keep examples from using more than 2 cores
data.table::setDTthreads(Sys.getenv("OMP_THREAD_LIMIT", unset = 2))

# single hue page
contrastChart(m = '10YR 3/3', hues = '10YR')


# multiple hue pages
contrastChart(m = '10YR 3/3', hues = c('10YR', '2.5Y'))


# contrast class, single hue
contrastChart(m = '10YR 3/3', hues = '10YR', style='CC')


# contrast class, multiple hues
# consider latticeExtra::useOuterStrips()
contrastChart(m = '10YR 5/6', hues = c('10YR', '2.5Y'), style='CC')