Planetside Software Forums

General => Terragen Discussion => Topic started by: pokoy on January 17, 2014, 04:31:12 AM

Title: Workflow idea - Simplified Lighting for test renders
Post by: pokoy on January 17, 2014, 04:31:12 AM
This is just an idea I had and I don't know if it's feasible or if it would improve anything at all. Here it goes:

Let's assume rendering test images takes 80% of the time you need on a project to get your final image. I think that - please correct me if I'm wrong - TG does a full evaluation of the atmosphere, together with cloud/fog/haze and sun sampling to determine the final light intensity, color and direction for every pixel, probably based on the general sampling parameter and some other simplifications.

Now if TG had a sky/dome light (preferably with importance sampling) that you could feed with a HDR image, this would allow for saving a lot of sky/atmosphere evaluation time for lighting the scene.

I guess you could so it by pre-calculating a HDR image of the sky/atmosphere internally and using that for test renderings instead of fully evaluating the atmosphere. This would be especially useful when tweaking ground shaders, displacements etc. As soon as you touch any of the sky/atmosphere parameters this map would need to be updated, of course, without any user interaction.

A nice side-effect would be that you'd be able to load an arbitrary HDR image for lighting (and reflections), regardless of the current atmosphere settings, which is probably useful for some people anyways.

I don't know if TG is doing something similar under the hood already, and I'm not sure if anyone would actually use a HDR image for lighting at all. But as I said, it's just an idea and I thought I'd post to hear your thoughts.