I was wondering if I can access information from lightmaps generated by Beast inside surface shaders, such as:
-
Lightmap UV. Not just the regular UV2 channel, but the one that is actually being used by lightmaps, after automatic atlasing (copy tilling and offset values doesn’t work for me because these values are related to single objects. By copying to materials I would share the same values for different objects, which is bad).
-
2D Texture. Lightmaps seems to multiply over everything no matter what shader is being used. But the texture itself is not accessible, unless you create another texture slot and re-assign it manually.
Are such informations available in surface shaders?
You could look at the shaders present that support it, they are available to download. Unsure if they are surface shader based but at least they show you how it works technically at the time.
The problems is that lightmaps are totally apart from the regular shaders. They are added internally…
they show up so they are in the compiled shader though 
so if you click on the shader on the material in unity and use the context menu to view the compiled shader you still should get the whole code that leads there.
on the surface shader side you don’t touch it, thats right, there it works automatically as it otherwise could not work at all in dual lightmap mode
Only if you add the #pragma debug directive.