What is light mapping?
A light map is a texture or group of textures that contains information about lighting in a 3-D scene. You can store the
lighting information in the alpha values of the light map, in the color values, or in both.
The picture on the left is a basic texture. The middle picture is the specular light map, and the right picture is the both
of them combined for the final product.
Lightmaps calculates all the light in the scene and bakes it in to a texture, then is automatically overlay on top of the
object material, to create the feeling of illumination. This sort of illumination is static, once the baking is on place you
can not modify it on real time, unless you bake it again with the new variations.
While testing is recommended to use smaller resolutions in order to get a quick result. Lightmaps as well as all the
other forms of baking in RENDERLights requires unwrapping.
If a model failed to unwrap, try to make it smaller. on your cad program you can separate objects on smaller components,
keep the count of objects small but don't weld too many complex objects together, that could cause troubles at the time of
unwrapping, remember that unwrapp will split every face in to a 4X4 texture map, and every face will be lay out in the map.
Explorer tree / Static Objects / Bake Lightmaps
First you need Unwrapp in order to bake the objects
Bake the models according to your needs, trial an error is needed in order to get correct results.
Use smothing on baking settings to get softer bake results.