Hey @brecht
https://projects.blender.org/boberfly/blender/src/branch/cycles_shared_lib
I've moved this one to Blender itself (I feel kind of silly that I didn't know of make cycles
until…
Hi @weizhen
That's great news! For spotlights, USDLux/Prman treats these exactly like sphere lights except it has "shaping" applied to it to be in the shape of a cone or an IES profile…
I remember that point/spot lights are an approximate of an oriented disc, so I am not sure if that has something to do with things, so I'll re-link an old patch from @Stefan_Werner here: https://a…
Hmm something different but it's worth making a note of it, it seems like un-normalising of lights only works for specular reflection and not diffuse for some reason:
I am not sure if area calculation should be -M_PI_4_F
or just -1.0f
for un-normalised ellipsed area lights though...