import math import re class Color: def to_rgb(self): raise Exception("Must implement to_rgb() in subclasses") class RGB: def __init__(self, r, g, b): self.r = r self.g = g self.b = b def to_rgb(self): return self class HSL(Color): def __init__(self, h, s, l): # noqa; E741 self.h = h self.s = s self.l = l # noqa; E741 @staticmethod def _hue_to_rgb(t1, t2, hue): if hue < 0: hue += 6 elif hue >= 6: hue -= 6 if hue < 1: return (t2 - t1) * hue + t1 elif hue < 3: return t2 elif hue < 4: return (t2 - t1) * (4 - hue) + t1 else: return t1 def to_rgb(self): hue = self.h / 60.0 if self.l <= 0.5: # noqa; E741 t2 = self.l * (self.s + 1) else: t2 = self.l + self.s - (self.l * self.s) t1 = self.l * 2 - t2 r = self._hue_to_rgb(t1, t2, hue + 2) g = self._hue_to_rgb(t1, t2, hue) b = self._hue_to_rgb(t1, t2, hue - 2) return RGB(r, g, b) class HWB(Color): def __init__(self, h, w, b): self.h = h self.w = w self.b = b @staticmethod def _hue_to_rgb(hue): if hue < 0: hue += 6 elif hue >= 6: hue -= 6 if hue < 1: return hue elif hue < 3: return 1 elif hue < 4: return 4 - hue else: return 0 def to_rgb(self): hue = self.h / 60.0 t1 = 1 - self.w - self.b r = self._hue_to_rgb(hue + 2) * t1 + self.w g = self._hue_to_rgb(hue) * t1 + self.w b = self._hue_to_rgb(hue - 2) * t1 + self.w return RGB(r, g, b) class CMYK(Color): def __init__(self, c, m, y, k): self.c = c self.m = m self.y = y self.k = k def to_rgb(self): r = 1.0 - min(1.0, self.c + self.k) g = 1.0 - min(1.0, self.m + self.k) b = 1.0 - min(1.0, self.y + self.k) return RGB(r, g, b) class Gray(Color): def __init__(self, g): self.g = g def to_rgb(self): return RGB(self.g, self.g, self.g) _x11_colors = { "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), "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), } _ws_re = re.compile(r"\s+") _token_re = re.compile(r"[A-Za-z_][A-Za-z0-9_]*") _hex_re = re.compile(r"#([0-9a-f]{3}(?:[0-9a-f]{3})?)$") _number_re = re.compile(r"[0-9]*(\.[0-9]*)") class ColorParser: def __init__(self, s): self._string = s self._pos = 0 def skipws(self): m = _ws_re.match(self._string, self._pos) if m: self._pos = m.end(0) def expect(self, s, context=""): if ( len(self._string) - self._pos < len(s) or self._string[self._pos : self._pos + len(s)] != s ): raise ValueError(f'bad color "{self._string}" - expected "{s}"{context}') self._pos += len(s) def expectEnd(self): if self._pos != len(self._string): raise ValueError('junk at end of color "%s"' % self._string) def getToken(self): m = _token_re.match(self._string, self._pos) if m: token = m.group(0) self._pos = m.end(0) return token return None def parseNumber(self, context=""): m = _number_re.match(self._string, self._pos) if m: self._pos = m.end(0) return float(m.group(0)) raise ValueError(f'bad color "{self._string}" - expected a number{context}') def parseColor(self): self.skipws() token = self.getToken() if token: if token == "rgb": return self.parseRGB() elif token == "hsl": return self.parseHSL() elif token == "hwb": return self.parseHWB() elif token == "cmyk": return self.parseCMYK() elif token == "gray" or token == "grey": return self.parseGray() try: r, g, b = _x11_colors[token] except KeyError: raise ValueError('unknown color name "%s"' % token) self.expectEnd() return RGB(r / 255.0, g / 255.0, b / 255.0) m = _hex_re.match(self._string, self._pos) if m: hrgb = m.group(1) if len(hrgb) == 3: r = int("0x" + 2 * hrgb[0], 16) g = int("0x" + 2 * hrgb[1], 16) b = int("0x" + 2 * hrgb[2], 16) else: r = int("0x" + hrgb[0:2], 16) g = int("0x" + hrgb[2:4], 16) b = int("0x" + hrgb[4:6], 16) self._pos = m.end(0) self.skipws() self.expectEnd() return RGB(r / 255.0, g / 255.0, b / 255.0) raise ValueError('bad color syntax "%s"' % self._string) def parseRGB(self): self.expect("(", 'after "rgb"') self.skipws() r = self.parseValue() self.skipws() self.expect(",", 'in "rgb"') self.skipws() g = self.parseValue() self.skipws() self.expect(",", 'in "rgb"') self.skipws() b = self.parseValue() self.skipws() self.expect(")", 'at end of "rgb"') self.skipws() self.expectEnd() return RGB(r, g, b) def parseHSL(self): self.expect("(", 'after "hsl"') self.skipws() h = self.parseAngle() self.skipws() self.expect(",", 'in "hsl"') self.skipws() s = self.parseValue() self.skipws() self.expect(",", 'in "hsl"') self.skipws() l = self.parseValue() # noqa; E741 self.skipws() self.expect(")", 'at end of "hsl"') self.skipws() self.expectEnd() return HSL(h, s, l) def parseHWB(self): self.expect("(", 'after "hwb"') self.skipws() h = self.parseAngle() self.skipws() self.expect(",", 'in "hwb"') self.skipws() w = self.parseValue() self.skipws() self.expect(",", 'in "hwb"') self.skipws() b = self.parseValue() self.skipws() self.expect(")", 'at end of "hwb"') self.skipws() self.expectEnd() return HWB(h, w, b) def parseCMYK(self): self.expect("(", 'after "cmyk"') self.skipws() c = self.parseValue() self.skipws() self.expect(",", 'in "cmyk"') self.skipws() m = self.parseValue() self.skipws() self.expect(",", 'in "cmyk"') self.skipws() y = self.parseValue() self.skipws() self.expect(",", 'in "cmyk"') self.skipws() k = self.parseValue() self.skipws() self.expect(")", 'at end of "cmyk"') self.skipws() self.expectEnd() return CMYK(c, m, y, k) def parseGray(self): self.expect("(", 'after "gray"') self.skipws() g = self.parseValue() self.skipws() self.expect(")", 'at end of "gray') self.skipws() self.expectEnd() return Gray(g) def parseValue(self): n = self.parseNumber() self.skipws() if self._string[self._pos] == "%": n = n / 100.0 self.pos += 1 return n def parseAngle(self): n = self.parseNumber() self.skipws() tok = self.getToken() if tok == "rad": n = n * 180.0 / math.pi elif tok == "grad" or tok == "gon": n = n * 0.9 elif tok != "deg": raise ValueError('bad angle unit "%s"' % tok) return n _color_re = re.compile( r"\s*(#|rgb|hsl|hwb|cmyk|gray|grey|%s)" % "|".join(_x11_colors.keys()) ) def isAColor(s): return _color_re.match(s) def parseColor(s): return ColorParser(s).parseColor()