R Unlimited CZ

Is that really light effect or only good textures? :

That's called 'static lights'. When the map is built, it calculates all the light surfaces and makes something like "light textures" - a textures made of light that are put in various places all over the map. Then that 'textures' are saved inside the map.
This kind of lights/shadows are static - meaning they can't move, but they are enough to fulfill their purpose.

So generally, it is a light AND a texture

Those "light textures" are called lightmaps. Try using command /r_lightmap 1, which allows you to only see the lightmaps, textures aren't rendered(I think it's not even cheat protected in 1.1).

By default, the lightmaps have a low resolution( otherwise the .bsp file would be huge ). Something like 128x128. Now, while creating the map, the creator can give some surfaces higher resolution lightmaps when it's needed. Most map makers don't really take advantage of this feature, but the pictures that you posted are a good example of how it should be used.

oh, thanks !