well i am making a warrior now and i have a problem with the material of his shield as it should consist of 2 materials
a back ground and some Decoration drawings
its not the problem i know it can be done with the UV mapping but the thing is that i need this Decoration to be glowing and the back ground be little diffuse
so i have been thinking if there is a way i can make only the Decoration drawing glowing like according to a black and white map? like defining a material with a map?
like alpha map or something?
i am using cycles by the way
would be soooooo good if you made a node tree snapshot of it 
:spin:
You mean somthing like this?
For somthing like that you can use a noodle kinda like this:
“Mask” is a grayscale image, with the whiter parts being the lit stuff. “BKG” is the background image. And you can replace the Voronoi+Color ramp with whatever texture you want the lit part to be. There is lots of room for tweaking; and with a few additional nodes and a copy of part of the stuff there you can even have the light be way stronger without the actual lightsource having it’s colors distorted when viewed by the camera.
Let me know if you got any questions.