View Full Version : Rough surface means longer render time?

01-13-2018, 01:52 AM

I am testing lw18 and I find that the higher the roughness values are on materials the longer it takes for AA to clean up, all other settings remain the same (samples, GI,...). For example, a concrete floor surface with low roughness values takes only half of rendering time that a hi roughness value takes. Is this how engine is supposed to work?

Best regards

01-13-2018, 04:50 AM
Yes, because it requires more samples. Se here...


01-13-2018, 08:44 AM
If you want to have steady render times disable adaptive anti-aliasing and use fixed Minimum Samples. Obviously noise will be still visible. But not a big problem in test renders and previewing.

Disabling Adaptive AA, and using Brute Force GI, with just 1 Ray, is a way to have ultra responsive VPR previewer.

01-13-2018, 09:08 PM
this sounds like a candidate for a toggle - fast vpr/your final render settings ;)

01-14-2018, 03:12 AM
this sounds like a candidate for a toggle - fast vpr/your final render settings ;)

You can do it right now, to some level:

Render Globals, pick up top drop-list, open shelf,
drop-list, Add to Shelf, give name "Full",
reduce to minimum settings,
drop-list, Add to Shelf. give name "Quick",
Double click on preset in Shelf - settings changed.

But it won't unfortunately store info about Adaptive AA in Camera settings (this can speed up hundred percent refinement in VPR)..

Draft mode should be such preset user can edit. That's how I would do it. Instead of hardcoding what is limited. And accessible from short-cut.

I am going to make video tutorial.

01-14-2018, 11:07 AM
Thank you for answers! I almost forgot to say thanks as I got stuck in RebelHill's tutorials :) They are really amazing. I am very surprised how you manage to explain this quite difficult subject so straight forward and simple. Great job!

@RebelHill: Since I use LW primarily for architectural viz, would you be interested in making an arch viz tutorial? Focusing on scene setup and rendering?

Best regards