Emission from textures - other question

[kbentley]

Hi all,

I am trying to perform an energy calculation, and while I feel like I've read over the docs fairly well, I don't think I see something that exactly matches what I am trying to achieve. Let me explain the situation - if the functionality is missing, I may be interested in contributing it.

I have a scene consisting of an environment (trees, terrain, etc), object models (cars, trucks, pedestrians), and emitters (directional sun light). I am interested in rendering this scene in different bands, mostly visible and long wave (8000 - 16000) nm for automotive AI applications. The models have a visible texture, and have a texture that represents the temperature of the model - IE the temperature of a persons face, the temperature of the road, and so on. All of my models are obj's, mtl, and texture files, with some associated normal map, and material map.

The visible rendering isn't so bad, it's the long wave rendering that is giving me trouble. I'd like to use the temperature textures to tell mitsuba what the exitance should be for the models, or at least find a way to convert them directly into an 'exitance map' and use them. Additionaly, I'd like to be able to define a responsivity curve, with a lower and upper wavelength, etc. Any pointers? I had been doing a lot of this (approximately) with shaders, but times are changing!