Color.CSS.Names (Color v0.4.0)

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The 148 named colors defined by CSS Color Module Level 4, mapped to their 8-bit sRGB values.

Summary

Functions

all()

Returns the raw CSS-name → {r, g, b} map (0..255 bytes).

known?(name)

Returns whether the given name is a known CSS color name.

lookup(name)

Looks up a CSS named color and returns its 8-bit sRGB components.

names()

Returns the full list of CSS color name strings.

nearest(input)

Finds the CSS named color that is perceptually closest to the given color using CIEDE2000.

normalize(name)

Normalises a color-name string: lowercases and strips underscores, hyphens and whitespace. Exposed so callers can match on the canonical form.

Functions

all()

@spec all() :: %{required(String.t()) => {0..255, 0..255, 0..255}}

Returns the raw CSS-name → {r, g, b} map (0..255 bytes).

Returns

  • A map.

known?(name)

@spec known?(atom() | String.t()) :: boolean()

Returns whether the given name is a known CSS color name.

Arguments

  • name is a string or atom.

Returns

  • A boolean.

Examples

iex> Color.CSS.Names.known?("red")
true

iex> Color.CSS.Names.known?(:misty_rose)
true

iex> Color.CSS.Names.known?("notacolor")
false

lookup(name)

@spec lookup(atom() | String.t()) ::
  {:ok, {0..255, 0..255, 0..255}} | {:error, Exception.t()}

Looks up a CSS named color and returns its 8-bit sRGB components.

The lookup is case-insensitive, accepts strings or atoms, and ignores underscores, hyphens and whitespace in the name. So "rebecca purple", :rebecca_purple, "Rebecca-Purple" and "rebeccapurple" all resolve to the same color. Both US and UK spellings (gray / grey) are supported. "transparent" maps to (0, 0, 0) — the alpha is the caller's concern.

Arguments

  • name is a string or an atom.

Returns

  • {:ok, {r, g, b}} with each channel in 0..255.

  • {:error, reason} if the name is unknown.

Examples

iex> Color.CSS.Names.lookup("rebeccapurple")
{:ok, {102, 51, 153}}

iex> Color.CSS.Names.lookup("Red")
{:ok, {255, 0, 0}}

iex> Color.CSS.Names.lookup(:misty_rose)
{:ok, {255, 228, 225}}

iex> Color.CSS.Names.lookup("chroma green")
{:ok, {0, 177, 64}}

names()

@spec names() :: [String.t()]

Returns the full list of CSS color name strings.

Returns

  • A sorted list of strings.

nearest(input)

@spec nearest(Color.input()) ::
  {:ok, {String.t(), Color.SRGB.t(), float()}} | {:error, Exception.t()}

Finds the CSS named color that is perceptually closest to the given color using CIEDE2000.

Arguments

Returns

  • {:ok, {name, %Color.SRGB{}, delta_e}} on success.

Examples

iex> {:ok, {name, _srgb, _de}} = Color.CSS.Names.nearest(%Color.SRGB{r: 1.0, g: 0.01, b: 0.0})
iex> name
"red"

normalize(name)

@spec normalize(String.t()) :: String.t()

Normalises a color-name string: lowercases and strips underscores, hyphens and whitespace. Exposed so callers can match on the canonical form.

Arguments

  • name is a string.

Returns

  • The normalised string.

Examples

iex> Color.CSS.Names.normalize("Misty Rose")
"mistyrose"

iex> Color.CSS.Names.normalize("rebecca-purple")
"rebeccapurple"