I’ve been trying to figure out how to do a correct luminosity map for a long time. For anybody unfamiliar with what a luminosity map is, allow me to explain it a little:

A luminosity map is a grayscale image, which looks much like a alpha channel. What a luminosity map does is make parts of the bitmap is it working with self illuminate. For example, if I had a button, or a screen, which I wanted to show up as bright, but not the entire bitmap, I would use a luminosity map, and where the button or screen is, I would paint it basically white, while the rest of the image remains black. This whiteness would give the bitmap with the button or screen on it the necessary value it needs to become lit, regardless of what the lighting in the map or on the object was, that button or screen would always be at 100% light strength if it has a 255 value for the channel.

I’ve asked questions like this in the past, and I’ve been told it can be done with shaders. Unfortunately, I haven’t got a clue how it can be done with shaders, and if anybody has a working example of this system and would like to share it, please do. If not, any pointing towards the right direction to getting something like this to work would be equally fantastic.

Thanks in advance for any assistance you may render.