Lets say I have a window on a texture of a spaceship and I want it glow, as if there is subtle light coming from inside the ship. How would I go about doing that?
I had an idea of using a selecting the windows and adding an emission shader to it.
Make the window an emission material and use the image as a texture? Make it a low brightness lamp should work fine.
Use emission, consider doing some compositing.
Use nodes and mix your texture with emission shader node.