Trichromatic Vision

The human eye has two different types of cells that respond to light.

• rods - more sensitive in low light, produce shades of gray
• cones - less sensitive, produce color

There are three types of cone cells, each with different color sensitivities.

Any color humans see is a mixture of these three primary colors.

Secondary colors have equal mixtures of two primary colors.

Computer Display Color - 24 bit RGB colors

The color of each pixel is a mixture of red, green, and blue, or RGB. The amount of each color is represented by a number from 0 - 255. In hex, each color ranges from 0 - FF.

Color	Decimal Range	Hex Range
Red (R)	0 - 255	0 - FF
Green (G)	0 - 255	0 - FF
Blue (B)	0 - 255	0 - FF

Color Demonstration

Link to color demo

Creating Color with Racket

Use the make-color function to create any 24-bit color.

;; make-color : number number number -> color

;; example - to create red (make-color 255 0 0)