Rendering ZBrush Displacement-Maps In External Renderers (May 9th: 2nd file added)

[policarpo]

my test using the findings discovered by our ZB C4D boys.

There's some weird banding, if you look at the nose in particular.

Render times are a little high I guess because of the displacement and upped Subdivisions.

Good to see either way...looking like we can use zBrush with some creative workarounds.

Cheers!

[MDB101]

skycastle: Can you post your specs with your Prman settings?? Im doing the same tests but with uhh bad results thnx in advance

[Julien]

MAX 6.0, thats the viewport view...(and a render)
Just a meshsmooth and standard displace modifier, luminance center at 0.5 and strength=17

It just mean that if anything else fails, in MAX, you can still use max displace to get the result you want. But no micropoly displacement here...


Julien

Oh, and by the way.. thanks Pixolator for the nice head model

[Zeddicus]

My test render using 2D mapping in Max/Vray. Look ma! No banding! Though I can now make it appear on demand, hehe.



By the way Cornel, I see lots banding in your C4D displacement image. Just thought I'd quickly point it out.

Edit: Don't know if this matters to anyone but thought I'd add it on to this post for the heck of it. Vray in 3D displacement mode looked pretty much identical to the 2D mode version. Only real difference was time. In 2D mode render time was 0 minutes 11 seconds, and in 3D mode 5 minutes 7 seconds. Quite a difference, and I was using the same fairly conservative render settings for both (very close to defaults, nothing special really).

[kobi1kobi]

Julien, do you happen to know if it's possible to use maxman with max 6 and render the model as SubD?
might be nice (if I can figure out how to do it in maya )

[Zeddicus]

Since no one has tried Max6+MentalRay yet, here is the best I could do. Can't really do anything about the banding like I can with Vray unfortunately (like lowering the blur setting in the material editor). Mental Ray in Max seems to ignore those settings, so I figure the default 1.0 blur is being applied and can't be changed. Playing with the various dispalcement settings can mitigate it some what, but also tends to make for a lower quality displacement at the same time (looks less like banding and more like a bumpy orange skin). No big deal to me though, since I don't really use MR for anything at the moment.

PS: Yeah, could be considered a failure I suppose. Figured I'd post it here anyways though so that no one got mad at Zbrush when trying to use it, hehe.

[reboren]

quote:

---

-subtract 0,627 from that value .. this seems to be necessary because "no displacement" does not seem to be 0,5 in the provided texture, but 0,627 instead

---

This is important, why this value rray how did you derive it ?

[pooverfish]

Another vray test.

The displacement values here are

13.344 with -6.672 shift

These values are based on the displacment value given by pixolator and the autoscale value in the OBJ (use a text editor to open the file, it is in the header), there should be no need to guess this. I'll put up a zscript/maxscript combination to do all this automatically once I have put a simple interface on it.

[MDB101]

pooverfish!!! Hows the weather over there in Aussi! Its me Eugene at Frantic Films Everybody in 3d is trying to figure out the right way of doing this mabe yah can help us out again we got PRman and Vray up and ready. nice seenin yeah again.

[pooverfish]

Hey man, good to see you here

The weather is a damn site better than where you are, cooling down a bit although it was 32c the other day.

Not sure what the prman settings are, but the scripts I have should make it a snap to get the values right, at least with vray. The prman stuff should also be done by numbers.

I'll get them out this weekend and let you know.

cheers,
grant

[Zeddicus]

Pooverfish: Your scripts sound interesting, looking forward to them to make life a little bit simpler, hehe. Not fussy so I used a guesstimate for mine and was very close (basically just eyeballed it). Amount=+14 Shift=-7

[spidex]

scott,
how did u find out abt the value for alpha gain ? 14.. thats pretty darn high from the suppose 0.8

[moob]

.834 / .0625 not sure if thats the right way to do it but that gives the value

[Scott Spencer]

Spidex:

I just went with trial and error having experienced the fact the alpha gain value will increase the displacment I pumped it up and kept the offset locked at 1/2 that value. I then work my way down to a suitabkle render always keeping the offset and the gain proportinally locked.
Otherwise the model will "bloat"

Trial and error : )

Scott

[squeige]

Here`s my test for Mental Ray, I imported poly to maya rotated 90 degrees and scale to about .4
reason being is zbrush import/exports defaults on 4 so in my scene the object was too larger

then I converted to a subd surf and added a subd approx node, I don`t understand why all these tuts and all these people use a disp approx since to all my testing whenever u use a surf approx or a subd approx node it overrides it.
my settings where something like
1 to 4
lenght/distance/angle
2.5

approx rendertime 40 secs. with shadow maps and 2 other surfaces