Jagged Displacement Issue - Roof Sheeting

[Dariusz Makowski (Dadal)]

The subdiv is the same thins as you apply turbo smooth + displace and texture in to it. It has different algorithms to deal with subdivision as well as its a lot faster to manage from memory point of view. Basically lets say (imaginative numbers) a car has 100k polygons, TS 1 = 400k polygons, TS 2 = 1.6 mil polygons TS 3 = 6.4 mil polygons.
Now if you use displacement in subdivision mode is exactly the same case Disp_subD 1 = 400k polygons/ Disp_subD 2 = 1.6mil polygons / Disp_subD 3 = 6.4mil polygons. Now they all will look pretty much exactly the same. The only difference is that TS 3 will eat up 4gb(not actual number) of ram and Disp_subD 3 will yeat 200mb ram. Displacement is being loaded and generated dynamically at render bucked level. Where as TS has to be pre-calculated.

[LarsSonparsson]

I agree about everything. Yep, that's the way how subdivision displacement works. ...or should we call it subdivision surfaces?

But I was just trying to show my point about the 3D displacement. So that the "Max Subdivs" number doesn't have any effect to it. Only edge length matters.
Somehow that is a common mistake people are making. Trying to adjust "Max Subdivs" to get better or faster displacement.

I think that the whole "Max subdivs" should be greyed out when 2D or 3D mode is selected, so it wont confuse people.

[vlado]

I think that the whole "Max subdivs" should be greyed out when 2D or 3D mode is selected, so it wont confuse people.

Yes, you are right, we should probably do that.

Best regards,
Vlado

[Morne]

Thanks all...

Any ideas on this now: I'm getting lots of gi blotches on the displaced sheeting, but everywhere else it is smooth. I eventually went with 2D displacement. Juts the gi blotches giving me issues now.

My irmap settings are medium preset with HSP sub on 120 and inter samples on 40
also tried 160 and 140 and also tried 50 and 40, doesnt seem to make a difference.

LC is default but with 2000 subs, use lc for glossy ticked, retrace ticked on 0.5 and also pre-filter on 20

[Morne]

Here's a crop of my RAWGi

[Dariusz Makowski (Dadal)]

what are ur settings?

[Morne]

what are ur settings?

My irmap settings are medium preset with HSP sub on 120 and inter samples on 40
also tried 160 and 140 and also tried 50 and 40, doesnt seem to make a difference.

LC is default but with 2000 subs, use lc for glossy ticked, retrace ticked on 0.5 and also pre-filter on 20

[Dariusz Makowski (Dadal)]

strange. Can you take a screenshot maybe? I'm bad at visualizing that

Dont pre-filter LC. leave it unfiltered. Only use for glossy and for retrace treshold. Also tick on in IRR to check samples visibility please.

[Morne]

ok seems it ended up being the 2D displacement that was the problem. 3D Displacement looked more or less the same in RawGI, but the beauty pass looked 1000 times more defined and crisp

[Dariusz Makowski (Dadal)]

Oh interesting! Thats for pointer. I gotta now run and redo my tests