darken
Darkens the color by the specified ratio.
This function darkens the color by adjusting its tone based on the provided ratio. A ratio of 1.1 darkens the color to a slightly darker tone, while values greater than 1.1 will darken the color further. If the resulting tone is invalid, the original color is returned.
Receiver
The Color to darken.
Return
The darkened Color, or the original color if the darkened color is not valid.
Parameters
ratio
The ratio by which to darken the color; must be greater than 0.0.