Function changeLightness

changeLightness(
rgb: Rgb,
amount: Partial<{ delta: number; fixed: number; pdelta: number }>,
): Rgb
Sets the lightness value.

Amount to change:
- 'fixed': a fixed amount
- 'delta': increase/decrease by this amount
- 'pdelta': proportion of current value to change by ('percentage delta')
Use negative values to decrease
Parameters
- rgb: Rgb
  Colour
- amount: Partial<{ delta: number; fixed: number; pdelta: number }>
  Amount to change
Returns Rgb
- Defined in visual/src/colour/srgb.ts:243