Merge pull request #1473 from Omikhleia/1440-color-parsing

core/color.lua

@@ -0,0 +1,213 @@
+local colornames = {
+  aliceblue = { 240, 248, 255 },
+  antiquewhite = { 250, 235, 215 },
+  aqua = {  0, 255, 255 },
+  aquamarine = { 127, 255, 212 },
+  azure = { 240, 255, 255 },
+  beige = { 245, 245, 220 },
+  bisque = { 255, 228, 196 },
+  black = {  0, 0, 0 },
+  blanchedalmond = { 255, 235, 205 },
+  blue = {  0, 0, 255 },
+  blueviolet = { 138, 43, 226 },
+  brown = { 165, 42, 42 },
+  burlywood = { 222, 184, 135 },
+  cadetblue = {  95, 158, 160 },
+  chartreuse = { 127, 255, 0 },
+  chocolate = { 210, 105, 30 },
+  coral = { 255, 127, 80 },
+  cornflowerblue = { 100, 149, 237 },
+  cornsilk = { 255, 248, 220 },
+  crimson = { 220, 20, 60 },
+  cyan = {  0, 255, 255 },
+  darkblue = {  0, 0, 139 },
+  darkcyan = {  0, 139, 139 },
+  darkgoldenrod = { 184, 134, 11 },
+  darkgray = { 169, 169, 169 },
+  darkgreen = {  0, 100, 0 },
+  darkgrey = { 169, 169, 169 },
+  darkkhaki = { 189, 183, 107 },
+  darkmagenta = { 139, 0, 139 },
+  darkolivegreen = {  85, 107, 47 },
+  darkorange = { 255, 140, 0 },
+  darkorchid = { 153, 50, 204 },
+  darkred = { 139, 0, 0 },
+  darksalmon = { 233, 150, 122 },
+  darkseagreen = { 143, 188, 143 },
+  darkslateblue = {  72, 61, 139 },
+  darkslategray = {  47, 79, 79 },
+  darkslategrey = {  47, 79, 79 },
+  darkturquoise = {  0, 206, 209 },
+  darkviolet = { 148, 0, 211 },
+  deeppink = { 255, 20, 147 },
+  deepskyblue = {  0, 191, 255 },
+  dimgray = { 105, 105, 105 },
+  dimgrey = { 105, 105, 105 },
+  dodgerblue = {  30, 144, 255 },
+  firebrick = { 178, 34, 34 },
+  floralwhite = { 255, 250, 240 },
+  forestgreen = {  34, 139, 34 },
+  fuchsia = { 255, 0, 255 },
+  gainsboro = { 220, 220, 220 },
+  ghostwhite = { 248, 248, 255 },
+  gold = { 255, 215, 0 },
+  goldenrod = { 218, 165, 32 },
+  gray = { 128, 128, 128 },
+  grey = { 128, 128, 128 },
+  green = {  0, 128, 0 },
+  greenyellow = { 173, 255, 47 },
+  honeydew = { 240, 255, 240 },
+  hotpink = { 255, 105, 180 },
+  indianred = { 205, 92, 92 },
+  indigo = {  75, 0, 130 },
+  ivory = { 255, 255, 240 },
+  khaki = { 240, 230, 140 },
+  lavender = { 230, 230, 250 },
+  lavenderblush = { 255, 240, 245 },
+  lawngreen = { 124, 252, 0 },
+  lemonchiffon = { 255, 250, 205 },
+  lightblue = { 173, 216, 230 },
+  lightcoral = { 240, 128, 128 },
+  lightcyan = { 224, 255, 255 },
+  lightgoldenrodyellow = { 250, 250, 210 },
+  lightgray = { 211, 211, 211 },
+  lightgreen = { 144, 238, 144 },
+  lightgrey = { 211, 211, 211 },
+  lightpink = { 255, 182, 193 },
+  lightsalmon = { 255, 160, 122 },
+  lightseagreen = {  32, 178, 170 },
+  lightskyblue = { 135, 206, 250 },
+  lightslategray = { 119, 136, 153 },
+  lightslategrey = { 119, 136, 153 },
+  lightsteelblue = { 176, 196, 222 },
+  lightyellow = { 255, 255, 224 },
+  lime = {  0, 255, 0 },
+  limegreen = {  50, 205, 50 },
+  linen = { 250, 240, 230 },
+  magenta = { 255, 0, 255 },
+  maroon = { 128, 0, 0 },
+  mediumaquamarine = { 102, 205, 170 },
+  mediumblue = {  0, 0, 205 },
+  mediumorchid = { 186, 85, 211 },
+  mediumpurple = { 147, 112, 219 },
+  mediumseagreen = {  60, 179, 113 },
+  mediumslateblue = { 123, 104, 238 },
+  mediumspringgreen = {  0, 250, 154 },
+  mediumturquoise = {  72, 209, 204 },
+  mediumvioletred = { 199, 21, 133 },
+  midnightblue = {  25, 25, 112 },
+  mintcream = { 245, 255, 250 },
+  mistyrose = { 255, 228, 225 },
+  moccasin = { 255, 228, 181 },
+  navajowhite = { 255, 222, 173 },
+  navy = {  0, 0, 128 },
+  oldlace = { 253, 245, 230 },
+  olive = { 128, 128, 0 },
+  olivedrab = { 107, 142, 35 },
+  orange = { 255, 165, 0 },
+  orangered = { 255, 69, 0 },
+  orchid = { 218, 112, 214 },
+  palegoldenrod = { 238, 232, 170 },
+  palegreen = { 152, 251, 152 },
+  paleturquoise = { 175, 238, 238 },
+  palevioletred = { 219, 112, 147 },
+  papayawhip = { 255, 239, 213 },
+  peachpuff = { 255, 218, 185 },
+  peru = { 205, 133, 63 },
+  pink = { 255, 192, 203 },
+  plum = { 221, 160, 221 },
+  powderblue = { 176, 224, 230 },
+  purple = { 128, 0, 128 },
+  rebeccapurple = { 102, 51, 153 },
+  red = { 255, 0, 0 },
+  rosybrown = { 188, 143, 143 },
+  royalblue = {  65, 105, 225 },
+  saddlebrown = { 139, 69, 19 },
+  salmon = { 250, 128, 114 },
+  sandybrown = { 244, 164, 96 },
+  seagreen = {  46, 139, 87 },
+  seashell = { 255, 245, 238 },
+  sienna = { 160, 82, 45 },
+  silver = { 192, 192, 192 },
+  skyblue = { 135, 206, 235 },
+  slateblue = { 106, 90, 205 },
+  slategray = { 112, 128, 144 },
+  slategrey = { 112, 128, 144 },
+  snow = { 255, 250, 250 },
+  springgreen = {  0, 255, 127 },
+  steelblue = {  70, 130, 180 },
+  tan = { 210, 180, 140 },
+  teal = {  0, 128, 128 },
+  thistle = { 216, 191, 216 },
+  tomato = { 255, 99, 71 },
+  turquoise = {  64, 224, 208 },
+  violet = { 238, 130, 238 },
+  wheat = { 245, 222, 179 },
+  white = { 255, 255, 255 },
+  whitesmoke = { 245, 245, 245 },
+  yellow = { 255, 255, 0 },
+  yellowgreen = { 154, 205, 50 }
+}
+
+local color = pl.class({
+  type = "color",
+  -- Default values amount to much "darkness in the void"
+  r = nil,
+  g = nil,
+  b = nil,
+  c = nil,
+  m = nil,
+  y = nil,
+  k = nil,
+  l = nil,
+ })
+
+function color:_init (input)
+  local c = self:parse(input)
+  for k, v in pairs(c) do
+    self[k] = v
+  end
+  return self
+end
+
+function color.parse (_, input)
+  local r, g, b, c, m, y, k, l
+  if not input or type(input) ~= "string" then
+    SU.error("Not a color specification string (" .. tostring(input) .. ")")
+  end
+  local named = colornames[string.lower(input)]
+  if named then
+    return { r = named[1] / 255, g = named[2] / 255, b = named[3] / 255 }
+  end
+  r, g, b = input:match("^#(%x%x)(%x%x)(%x%x)$")
+  if r then
+    return { r = tonumber("0x"..r)/255, g = tonumber("0x"..g)/255, b = tonumber("0x"..b)/255 }
+  end
+  r, g, b = input:match("^#(%x)(%x)(%x)$")
+  if r then
+    return { r = tonumber("0x"..r)/15, g = tonumber("0x"..g)/15, b = tonumber("0x"..b)/15 }
+  end
+  c, m, y, k = input:match("^(%d+%.?%d*)%s+(%d+%.?%d*)%s+(%d+%.?%d*)%s+(%d+%.?%d*)$")
+  if c then
+    return { c = tonumber(c)/255, m = tonumber(m)/255, y = tonumber(y)/255, k = tonumber(k)/255 }
+  end
+  c, m, y, k = input:match("^(%d+%.?%d*)%%%s+(%d+%.?%d*)%%%s+(%d+%.?%d*)%%%s+(%d+%.?%d*)%%$")
+  if c then
+    return { c = tonumber(c)/100, m = tonumber(m)/100, y = tonumber(y)/100, k = tonumber(k)/100 }
+  end
+  r, g, b = input:match("^(%d+%.?%d*)%s+(%d+%.?%d*)%s+(%d+%.?%d*)$")
+  if r then
+    return { r = tonumber(r)/255, g = tonumber(g)/255, b = tonumber(b)/255 }
+  end
+  r, g, b = input:match("^(%d+%.?%d*)%%%s+(%d+%.?%d*)%%%s+(%d+%.?%d*)%%$")
+  if r then
+    return { r = tonumber(r)/100, g = tonumber(g)/100, b = tonumber(b)/100 }
+  end
+  l = input:match("^(%d+.?%d*)$")
+  if l then
+    return { l = tonumber(l)/255 }
+  end
+  SU.error("Unparsable color " .. input)
+end
+
+return color

core/color_spec.lua

@@ -0,0 +1,43 @@
+SILE = require("core.sile")
+SU.warn = function () end
+
+describe("The color parser", function()
+  local parse = SILE.color
+  local rebecca = {
+    b = 0.6,
+    g = 0.2,
+    r = 0.4
+  }
+  local reddish = {
+    c = 0,
+    k = 0.3,
+    m = 0.81,
+    y = 0.81
+  }
+  it("should return the correct RGB values for a named color", function()
+    assert.is.same(parse("rebeccapurple"), rebecca)
+    assert.is.same(parse("RebeccaPurple"), rebecca)
+  end)
+  it("should return the correct RGB values for a hexadecimal specification", function()
+    assert.is.same(parse("#663399"), rebecca)
+    assert.is.same(parse("#639"), rebecca)
+  end)
+  it("should return the correct RGB values for a series of 3 numbers or percentages", function()
+    assert.is.same(parse("102 51 153"), rebecca)
+    assert.is.same(parse("40% 20% 60%"), rebecca)
+  end)
+  it("should return the correct CMYK values for a series of 4 numbers or percentages", function()
+    assert.is.same(parse("0% 81% 81% 30%"), reddish)
+    assert.is.same(parse("0 206.55 206.55 76.5"), reddish)
+  end)
+  it("should return the correct grayscale value for single number", function()
+    assert.is.same(parse("204"), { l = 0.8 })
+  end)
+
+  it("error if unable to parse", function()
+    assert.has.errors(function () parse("not_a_color") end)
+    assert.has.errors(function () parse(nil) end)
+    assert.has.errors(function () parse("") end)
+  end)
+end)
+