The Compose Color Node allows you to compose a color from its main components - a Red, Green, and Blue value and an Alpha value. Bitmaps or other textures can also be input into the slots and blended together using the Compose Color node.

In the example, an inverted Bitmap node is converted to a float value, using the Color to Float node. The value is used as the Red and Green inputs of a Compose Color node, leaving only Blue as a color value. This creates a blue-colored normal map, which can be used for various effects.  

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Red – Determines the amount of red in the color, when a texture is not assigned to this slot. The soft range is from 0 to 1. 

Green – Determines the amount of green in the color, when a texture is not assigned to this slot. The soft range is from 0 to 1. 

Blue – Determines the amount of blue in the color, when a texture is not assigned to this slot. The soft range is from 0 to 1. 

Alpha – Determines the alpha value for the generated color. A texture node can also be assigned to this slot.

Invert – When enabled, inverts the color output.