nix-config/lib/trucolor.cr
2017-11-13 12:09:32 -05:00

60 lines
2.1 KiB
Crystal

##################################################################################
#
# New Start: A modern Arch workflow built with an emphasis on functionality.
# Copyright (C) 2017 Donovan Glover
#
# Trucolor: A library that makes colorful output trivial.
# Copyright (C) 2017 Donovan Glover
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
#
##################################################################################
module Trucolor
# Formats a string *str* with the colors given in the turple *rgb* (0 <= rgb[i] <= 255)
def self.format(rgb, str)
return "\x1b[38;2;#{rgb[0]};#{rgb[1]};#{rgb[2]}m#{str}\x1b[0m"
end
# Goes through the colors in such a way that only 256 colors are used (0 <= n <= 255)
# @requires self.format()
def self.rainbow(n)
h = n / 43
f = n - 43 * h
t = f * 255 / 43
q = 255 - t
case h
when 0; return {255, t, 0}
when 1; return {q, 255, 0}
when 2; return {0, 255, t}
when 3; return {0, q, 255}
when 4; return {t, 0, 255}
when 5; return {255, 0, q}
end
return {0, 0, 0}
end
# Tests the format method by printing a rainbow of colors
# @requires self.rainbow()
def self.test()
n = -1
while (n += 1) < 256
print self.format(self.rainbow(n), "#{n}".rjust(3, '0')) + " "
print "\n" if (n + 1) % 16 == 0
end
end
end