Physically-Based Rendering

I’ve just finished integrating the Sun into the physically-based sky model. Here’s a test render:

Stanford Dragon in the sun

This was quite an useful exercise as it exposed some bugs in my light sampling code. Moreover at first I had overlooked the fact that, in the Preetham et al. paper, data for the Sun and sky radiance are not in the same units… Looks fine now, though

PS: Note that in the render above I had increased the Sun’s angular diameter in order to better visualise soft shadows.

It is perhaps not a priority at this point, but I felt like experimenting with the physical sky model by Preetham et al.

So far I have only crudely integrated skylight rendering. Sunlight and aerial perspective are next on my list.

Stanford dragon in the morning

I find this model quite simple to implement. In my opinion the downside is that it lacks the possibility to modify all the scattering parameters, and that it holds only for observers on the ground. Anyway, these limitations are pretty minor for me at the moment.