def hex_to_rgb(hex_string: Color) -> Tuple[int, int, int]:
hex_string = hex_string.lstrip('#')
assert len(hex_string) == 6
r = int(hex_string[0:2], 16)
g = int(hex_string[2:4], 16)
b = int(hex_string[4:6], 16)
return r, g, b
def _rgba(color: Color, alpha: int) -> Color:
"""
Args:
color: may be an RGB or RGBA color
"""
assert color.startswith('#') and len(color) in (7, 9), f'invalid RGB color: "{color}"'
assert 0 <= alpha < 255, f'alpha out of range: {alpha}'
return f'{color[:7]}{alpha:02x}'
def hex_to_rgb(hex_string: Color) -> RGB:
""" Returns hex string color as (r, g, b) tuple. """
hex_string = hex_string.lstrip('#')
assert len(hex_string) == 6
r = int(hex_string[0:2], 16)
g = int(hex_string[2:4], 16)
b = int(hex_string[4:6], 16)
return r, g, b
def set_color_alpha(color: Color, alpha: int) -> Color:
"""
Args:
color: may be an RGB or RGBA hex color string
alpha: the new alpha value (0-255)
"""
assert color.startswith('#') and len(color) in (
7, 9), f'invalid RGB color: "{color}"'
assert 0 <= alpha < 255, f'alpha out of range: {alpha}'
return f'{color[:7]}{alpha:02x}'
def set_color_alpha(color: Color, alpha: int) -> Color:
""" Returns `color` including the new `alpha` channel in hex format:
"#RRGGBBAA".
Args:
color: may be an RGB or RGBA hex color string
alpha: the new alpha value (0-255)
"""
assert color.startswith('#') and len(color) in (
7, 9), f'invalid RGB color: "{color}"'
assert 0 <= alpha < 256, f'alpha out of range: {alpha}'
return f'{color[:7]}{alpha:02x}'
