(Solved) Emission in PBR, how is it implemented?

bitinn

Hi,

Is there a layman explanation somewhere that explain how Emission / Emissive map affect the rendering of an object using common PBR implementation?

Let's ignore how emission affects other objects in the scene, that's Global Illumination's job, I kinda want to understand how does it affect the emissive object itself: is it more or less a simple color blending on top of albedo?

Thx!

ActionDawg

To answer the second question first, it's not a color blend on the albedo, but added on at the end of shading when all your terms are combined: LightOut = LightEmitted + LightReflected
This is a very simplified, but adequate top level view of the rendering equation for light moving outwards from a point on a surface.

From there, there isn't much to do in PBR to make emissive realistic besides use kelvin color temperature and handling the intensity values with real units like lumens or candelas. Sometimes engines don't go so far however and you just do it by eye.

Then its up to GI or path tracing or whatever your rendering solution.