source: rgbkbd/trunk/rgbkbd/color.py @ 71

#!/usr/bin/python

import random

class Color(object):
    """Represents a color for the keyboard"""
    def __init__(self, red=None, green=None, blue=None, rgb=None):
        # Expects integer values, no floats
        if rgb is None:
            rgb = (red, green, blue)
        else:
            rgb = tuple(rgb)
        if None in rgb:
            raise Exception("bad value in %r" % rgb)
        for name, value in zip(['red' , 'green', 'blue'], rgb):
            if not 0 <= value < 256:
                raise Exception("Bad value %s for %s" % (value, name))
        self.rgb  = rgb

    @classmethod
    def blend(cls, c1, c2, transparency):
        """Given two colors, return a color based on a weighted combination"""
        blended = [a+b for a, b in zip([(1 - transparency) * x for x in c1.rgb],
            [transparency * x for x in c2.rgb])]
        return cls(rgb=blended)

    @classmethod
    def average(cls, colors):
        """Return the mean color among the given colors"""
        return cls(rgb=[sum(x)/len(colors) for x in zip(*[c.rgb for c in colors])])

    @classmethod
    def fromstring(cls, hexstring):
        """Convert a 6-digit hex string into a Color object"""
        r = int(hexstring[0:2], 16)
        g = int(hexstring[2:4], 16)
        b = int(hexstring[4:6], 16)
        return cls(r, g, b)

    @classmethod
    def random8(cls, exclude=None):
        """Returns a random color from the 8 basic colors, optionally excluding
        a choice.
        """
        while True:
            candidate = cls(rgb=[random.choice([0,255]) for _n in range(3)])
            if not exclude or candidate != exclude:
                return candidate

    def __str__(self):
        """6-hex-digit representation of the color

        This is the representation used by ckb-daemon
        """
        return '%02x%02x%02x' % self.rgb

    def __cmp__(self, other):
        return cmp(self.rgb, other.rgb)

    def __eq__(self, other):
        return self.rgb == other.rgb

    def __hash__(self):
        return hash(self.rgb)


class Colors(object):
    """Pre-defined colors"""
    WHITE = Color.fromstring('ffffff')
    GREY = Color.fromstring('808080')
    DARK_GREY = Color.fromstring('404040')
    BLACK = Color.fromstring('000000')

    RED = Color.fromstring('ff0000')
    GREEN = Color.fromstring('00ff00')
    BLUE = Color.fromstring('0000ff')
    PURPLE = Color.fromstring('ff00ff')
    YELLOW = Color.fromstring('ffff00')
    CYAN = Color.fromstring('00ffff')
    DARKCYAN = Color.fromstring('004040')
    ORANGE = Color.fromstring('ff8000')