Color.rgb constructor
An RGB color.
Implementation
const Color.rgb(this.red, this.green, this.blue)
: assert(red < 256, '[red] must be less than 256'),
assert(red >= 0, '[red] must be greater than or equal to 0'),
assert(green >= 0, '[green] must be greater than or equal to 0'),
assert(green < 256, '[green] must be less than 256'),
assert(blue >= 0, '[blue] must be greater than or equal to 0'),
assert(blue < 256, '[blue] must be less than 256');