colorfast

{colorfast} is a package for converting R colors and hexadecimal colors to arrays of RGBA values, and packed integer format (suitable for native rasters).

What’s in the box

C API

The C-level functions for converting colors are now exported via the LinkingTo mechanism, which means other R packages can call the C functions provided by this package. See the “C API” vignette for more details.

Installation

This package can be installed from CRAN

install.packages('colorfast')

You can install the latest development version from GitHub with:

# install.package('remotes')
remotes::install_github('coolbutuseless/colorfast')

Pre-built source/binary versions can also be installed from R-universe

install.packages('colorfast', repos = c('https://coolbutuseless.r-universe.dev', 'https://cloud.r-project.org'))

Example

library(colorfast)

col_to_rgb(c("hotpink", "#abc", "#aabb99", "#aabb9980"))
#>       [,1] [,2] [,3] [,4]
#> red    255  170  170  170
#> green  105  187  187  187
#> blue   180  204  153  153
#> alpha  255  255  255  128
col_to_int(c("hotpink", "#abc", "#aabb99", "#aabb9980"))
#> [1]    -4953601    -3359830    -6702166 -2137408598

Benchmarks

The following benchmarks compare {colorfast} to {farver} and base R.

package Convert to RGBA array Convert to packed integer
Base R col2rgb() N/A
{farver} decode_colour() encode_native()
{colorfast} col_to_rgb() col_to_int()

Click to show raw benchmark results

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# R color names
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cols <- sample(colors(), 10000, T)


#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Check we all agree on the RGB representation
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a1 <- col_to_rgb(cols)
a2 <- col2rgb(cols, alpha = TRUE)
a3 <- farver::decode_colour(cols) |> t()
a3 <- rbind(a3, 255L)
rownames(a3) <- c('red', 'green', 'blue', 'alpha')
stopifnot(identical(a1, a2))
stopifnot(identical(a2, a3))


res_col <- bench::mark(
  `baseR         ` = col2rgb(cols, alpha = TRUE),
  `{farver}`       = decode_colour(cols),
  `{colorfast}`    = col_to_rgb(cols),
  check = FALSE
)
knitr::kable(res_col[,1:5])
expression min median itr/sec mem_alloc
baseR 16ms 16.2ms 61.51107 313KB
{farver} 565µs 585.4µs 1690.73415 117KB
{colorfast} 148µs 159µs 6175.15787 156KB 



#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#
# Hex colors
#
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cols <- sample(colors(), 100000, T) |>
  col_to_rgb() |>
  t() |>
  rgb(maxColorValue = 255)

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Check we all agree on the RGB representation
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
a1 <- col_to_rgb(cols)
a2 <- col2rgb(cols, alpha = TRUE)
a3 <- farver::decode_colour(cols) |> t()
a3 <- rbind(a3, 255L)
rownames(a3) <- c('red', 'green', 'blue', 'alpha')
stopifnot(identical(a1, a2))
stopifnot(identical(a2, a3))

#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# benchmark
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
library(farver)
res_hex <- bench::mark(
  baseR         = col2rgb(cols, alpha = TRUE),
  `{farver}`    = decode_colour(cols, alpha = TRUE),
  `{colorfast}` = col_to_rgb(cols),
  check = FALSE
)
knitr::kable(res_hex[,1:5])
expression min median itr/sec mem_alloc
baseR 2.83ms 3.02ms 329.2867 3.05MB
{farver} 885.6µs 1.03ms 955.3143 3.05MB
{colorfast} 478.51µs 561.35µs 1760.7057 1.53MB 



#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Conversion to packed int
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cols <- sample(colors(), 100000, T) |>
  col_to_rgb() |>
  t() |>
  rgb(maxColorValue = 255)


#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# benchmark
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
library(farver)
res_int <- bench::mark(
  `{farver}`    = encode_native(cols),
  `{colorfast}` = col_to_int(cols),
  check = TRUE
)

knitr::kable(res_int[,1:5])
expression min median itr/sec mem_alloc
{farver} 795µs 840µs 1180.887 397KB
{colorfast} 506µs 536µs 1777.459 391KB 




#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Conversion to packed int
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
cols <- sample(colors(), 10000, T) 


#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# benchmark
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
library(farver)
res_int2 <- bench::mark(
  `{farver}`    = encode_native(cols),
  `{colorfast}` = col_to_int(cols),
  check = TRUE
)

knitr::kable(res_int2[,1:5])
expression min median itr/sec mem_alloc
{farver} 550µs 563µs 1747.400 39.1KB
{colorfast} 144µs 149µs 6584.385 39.1KB