Cycles new microdisplacement testing, discussion and blend sharing

(Ace Dragon) #301

There’s still a way to get big memory savings though in the form of a geometry cache (the size determined by the user). The reason such a feature isn’t in yet is because Mai wants to get all of the core functionality done first (because it otherwise may only serve to slow down development due to the complexity it adds to the code).

Though once it’s in, it will create a slight penalty in the rendering speed if it is used (how much depending on the size).

(Indy_logic) #302

Hey Oscar, Looks like we are shit out of luck this time around. It does’t work on OS X. I love how this issue has largely gone unnoticed by the devs. The issue is that OpenSubDiv is not supported properly on OS X due to some stupid Apple issue with OpenGL. The end result is that it simply won’t build at all anymore so the Mac OS X builds have it disabled. The end result is that we cannot use the “Adaptive” feature (which comes from OSD) on Mac. Which of course really sucks super hard.

On another note: I noticed that the docs make no mention of this rather severe limitation. You would think there would be a big “Not working on OS X” in bold red letters. I’m also kind of shocked that there aren’t more Mac people crying about it here. I mean, usually you see more than one “Hey, this does’t work for me” posts.

(brecht) #303

I’m surprised no one reported a bug. It’s working fine in my own OS X build but apparently missing in the RC. Cycles is not affected by the OpenGL issue.

(matali) #304

I don’t know if it is a known limitation, but at the moment, Group instances get the detail level of the original object. Which means, if object “stone” is at 0,0,0 and instanced at 500,500,100 near the camera, it will get no subdivision (because the whole original object is smaller than a pixel viewed from so far). Is a fix for this worked on to take the nearest visible instance for the subdivision?

(nudelZ) #305

instancing does not work with adaptive subdivision at the moment

(BeerBaron) #306

It’s most likely a build configuration issue, you can disable OpenGL for OpenSubdiv. As far as I remember, the macOS maintainer stepped down a while ago and nobody has stepped up to replace him. Apple doesn’t provide a way to build Mac software without the purchase of an expensive Mac computer, so it just doesn’t get tested/supported the same way (the terrible graphics API support just adds insult to injury). If you’re adventurous, you may want to try building it yourself and use some of the build flags at the bottom of this page.

Also, keep in mind that the feature is “experimental”. It won’t be enabled by default, even in the next release.

(Lsscpp) #307

Being adventurous you could also make a dual boot with Linux, and work there when you need to do things that [sarcasm]the most advanced OS in the world[/sarcasm] can’t do

(Nexious) #308

When I change Bump to True in the settings it crashes blender. Is there a setting that I am missing?

(marcoG_ita) #309

Maybe drop a line in IRC , afaik both Brecht and Ton use Mac.

(Indy_logic) #310

Yeah, the issue is that it’s not a bug. That’s why I didn’t report it. I assumed someone had made the decision to just ignore it for now on Mac.

(Secrop) #311

That and vector displacement could be a big help in creating diversity in a scene!!

(brecht) #312

Regarding OpenSubdiv on OS X, hopefully we can get it into 2.78 still:

(Serin) #313

Question: Is it possible to pull the displaced mesh out as an object?

…probably a dumb question.

(Lsscpp) #314

Since the new “True” displacement occurs at rendertime, the only way is the old way. Then, no.

(Lsscpp) #315

Hello Blendix, I see that you more and more are involved again in Cycles stuff, and this is so important! Are there news on this side?

(Serin) #316

Damn. That’s a pain.
The thought was that it’d much easier to animate with the ‘true’ displacement in mind if one could see it in the non-rendered viewport.
Think planes or spacecraft flying around the displaced mesh etc etc.

(<== Lost? Click Me) #317

Hi Secrop, cheers for the guide.

Have you been able to apply the resulting map to the basic object successfully? The aim being to displace to the sculpted shape again. Multires level on the basic object matches the sculpt.

When I tried some of the form seemed there, but just. Need to swizzle the channels perhaps?

Not sure about directly. That said, try render a depth pass? Use it with a displacement modifier or something like this ?

Though if occluded it won’t quite be the same object.

(zeauro) #318

You can use a low poly copy of your mesh using a displace modifier for animation layout and render the high detailed one using Cycles microdisplacement texture.
Maybe bump effect in material display mode can be sufficient.

Currently, OpenSubdiv in blender offers no displacement ability. Maybe it will change with new viewport project.

(dumbnudge) #319

Are there plans to enable instancing? In production shots for animation pretty much everything in the animation file is a linked instance of individual asset files. Having this feature for productions would be huge, and I would gladly chip in for the development costs.

(Lsscpp) #320

Since nudelZ looks to have insights about the project, the use of “at the moment” may have a meaning