Here is a visualization of the RGB color space. The axis to the left shows the red channel increasing. The vertical axis is green. And the channel to the right is blue. We can’t see the interior of the cube showing intermediate values. All the values we can see in this particular have one or more channels at the maximum. Here’s a view inside the cube with the red and blue axes swapped. Next, this direction doesn’t really matter. The point inside the cube shows how sky blue is formed by the RGB values of 1 5th red, 3 5th green, and 4 5th blue. Another way to visualize the RGB color space, is to take a slice of the cube at these three corners. Each corner represents a single color channel at full intensity, with the other two channels off. For example this vertex is where green is set to one and red and blue are 0. By slicing a plane through these three corners, we’ll be able to see where red plus green plus blue equal 1. This slice gives another view of how these colors blend. This is what the next exercise is about.