Purple and Green Image Making

In this example we are using math functions to map a pixel's location into its color. We begin by making a new image that is 256 pixels by 256 pixels. This is convenient because it means that the valid x and y values are from 0 to 255 inclusive, which is exactly the same range as our color values. Therefore, we can directly use the x and y values as color values. If we use the x value as the red and blue values and the y value as the green, we get an interesting visual effect that blends purple and green. When the x value is greater than the y value, we will see more purple than green. When the y value is greater than the x value, the green will dominate. When x = y, the green and purple (red and blue) values will be equal. Whenever all three color values are equal we get a shade of gray.