This is a Game-Dev related question.
Let's say we modeled a simple piece of floor in Blender and applied a wood texture to it. From this plain texture, often referred to the base texture, we usually create some other maps, like:
- A bump/normal map.
- A specular map.
- A displacement map.
- An ambient occlusion (AO) map.
- And some more...
Finally, right before exporting this model, we usually bake all textures into a master texture (which is a single .jpg or .png file that contains all of the aforementioned textures combined). And voilà. We have a master texture and ready to be used in Unity (or Unreal Engine, or the game engine of your liking).
However, the more I dig into this designing/game-dev world, the more confused I get. This is so because Game Engines generally give you the possibility to attach all of the previously mentioned maps (normal, spec, displ, AO, ...) separately to the model. For example, in Unity 5, you can do that right into the shader:
1. First way of doing it: Baking all maps (normal, spec, displ, AO, ...) into a MASTER TEXTURE. Then using this master texture right inside of the Game Engine.
2. Second way of doing it: Importing all maps (normal, spec, displ, AO, ...) into the Game Engine. Then importing the model as well, and tell the shader what texture corresponds to what map (i.e. manually select all maps; see the first image).
All in all, what is the "most correct" way to apply texturing to a model inside of a game engine, out of the two I mentioned right above?