This video shows one of the ways you could pack multiple pieces of information into a single texture. The idea is to have more control over the look of an explosion in UE4 by combining normals, emission and opacity into a single texture.
You can download the latest version of the Texture Sheet ROP on GitHub. github.com/sideeffects/GameDevelopmentToolset/tree/Development
Or by using the update button on the Game Development Toolset shelf.
Download the UE4 examples files.
Place the TextureSheets folder in the Content folder of your project. Generated in 4.15.3