def saturation(x, value):
'''
Extends colors app saturation filter with relative changes using "+"
and "-".
Example usage:
{{ color|saturation:"+5" }}
{{ color|saturation:"-5" }}
{{ color|saturation:"50" }}
'''
x = expand_hex(x)
h, s, v = hex_to_hsv(x, False) if len(x) == 6 else x
# technically, saturation cannot increase _relatively_ from 0
# i.e. gray remains gray regardless of saturation increase
if s > 0:
if str(value).startswith('+'):
value = int(s) + int(value[1:])
if value > 100:
value = 100
if str(value).startswith('-'):
value = int(s) - int(value[1:])
if value < 0:
value = 0
else:
value = 0
return colors_saturation(x, value)
def hue(x, value):
'''
Extends colors app hue filter with relative changes using "+" and "-".
Example usage:
{{ color|hue:"+180" }}
{{ color|hue:"-180" }}
{{ color|hue:"180" }}
'''
x = expand_hex(x)
h, s, v = hex_to_hsv(x, False) if len(x) == 6 else x
if str(value).startswith('+'):
value = int(h) + int(value[1:])
if str(value).startswith('-'):
value = int(h) - int(value[1:])
# compensate for values falling outside the range 0-360
if int(value) > 360 or int(value) < 0:
value = int(value) % 360
return colors_hue(x, value)
def lightness(x, value):
'''
Extends colors app lightness filter with relative changes using "+" and "-".
Example usage:
{{ color|lightness:"+5" }}
{{ color|lightness:"-5" }}
{{ color|lightness:"50" }}
'''
x = expand_hex(x)
h, s, v = hex_to_hsv(x, False) if len(x) == 6 else x
if str(value).startswith('+'):
value = int(v) + int(value[1:])
if value > 100:
value = 100
if str(value).startswith('-'):
value = int(v) - int(value[1:])
if value < 0:
value = 0
return colors_lightness(x, value)
