Hello and welcome to this exercise about how to bake Global Illumination into just one texture. This is used mainly to import models to real-time 3D engines where objects have to be rendered at least 60 times per second.
Shadows in videogame engines are a very expensive process; however, if we bake the Global Illumination of an object in a texture then we can help out the engine and we can show better quality graphics!
I will use a 3 segmented teapot as a model; it's a low polygon model for videogames, so we'll stick to that rule for this tutorial (Fig.01).
The way of working the scene first is the same as if we are about to start work on any new scene; I downloaded 2 images from cgtextures.com, which is an excellent site for finding textures. I applied a brick material to the plane and a metal material to the teapot (Fig. 02)
This part of the tutorial depends on what result you're looking for, because this step is about giving illumination to the model. In my case I used V-Ray, and activated illumination global in the Renderer options, along with the GI environment option (skylight) (Fig.03).
The next step was to put an Omni light with "Vray shadows", activating the "area Shadow" option.
Before baking the illumination into a texture we must make renders, because the final render appearance will be the same as it will be when baking the textures (Fig.04a – c).