[eric nixon]

For carpets R2 works (see image), for a hairy welcome matt pretess disp is good (see image), for a shaggy rug use the grass modifier, or hair if your plugin supports that.

[feynman]

Sure, but like I mentioned, I'm working with Studio because there ain't no Maxwell Render plugin for Alias, Pro/E, or MATLAB, so it's all via OBJ export/import only. The new Grass can't be used either because I have to downgrade to 2.6 because resuming cooperative renders don't work with my PCs. So, shagging only via displacement which does not work without on the fly and adaptive which is very slow or by purchasing carpets at Turbosquid or wherever, which is a bummer but seemingly the only solution. Or do you know of an MXM that works with pretessellated and a high poly count of the object it's applied to? As you can see, in my case pretessellated and any polygon number on a plane always results in an absolutely flat looking object, as if no displacement or even bump was present.

[Mihai]

Did you try raising the displacement height? Also you can subdivide that plane a lot more than 8x8.

[polynurb]

sorry to hear that you are struggling in studio.. what is the problem with pretesselated?

i don't use studio but render from rhino. no problems with pretesselated mode here.
notice the subdivision setting of 0.1.. the plane i use has 1500x1500 polys, scale 1x1m.
it renders with a benchmark of ~900, fast machine though:

15 min render, carpet 1x1m, camera floating 50 cm above

[feynman]

@mihai Sure, 1cm - 5cm - 50cm, 1% - 5% - 10%, my plane is definitely 1x1 metres; tried with 64000 polygons - 1024000 polygons - 2560000 polygons; tried with the pretessellated default 16 subdivisions up to the maximum 100000 subdivisions...

@polynurb May need to install Rhino in the worst case, although I try to avoid it ;) But - how come that you have "only" 2250000 polygons and then set that subdivision number just so low at 0,1? What actually is the relationship between an object's polygon count and that pretessellated subdivision number that goes to a maximum of 10000? The higher the polygon count - the lower that figure should be, like in your case?

Did you try raising the displacement height? Also you can subdivide that plane a lot more than 8x8.

[polynurb]

asfaik there should not be a difference between the pretess and on the fly subdivision setting.
the pretesselation is calculated @export and will render much faster and is better choice except u render really large areas with high detail.


try to get subdivision as low as possible before you loose the desired effect; it is another factor that speeds rendering up.
i was exaggerating a bit with 0.1, just to show what is possible if the original object has a very high poly count.
in fact i think 1500 divisions/meter is very high resolution considering the real scale of objects.

*
it is a shame that rhino 5 development is so enervating.. because the plug-in itself is a breeze to use

[eric nixon]

asfaik there should not be a difference between the pretess and on the fly subdivision setting.

For the sake of thread sanity;.. this is not true.

0.1 may invoke a special mode, I wasnt aware that was a valid input.

[polynurb]

maybe it's my english...

do you mean that the identical object with the identical setting in the subdivision slot will have different appearance depending on if "on the fly" or "pretesselated" is chosen?

i thought they should look the same..

[feynman]

Well, in any case - downgrading to 2.6 (had to because of resuming coop renders faulty in my setup) makes displacement work again as I expected; high poly count, low subdivision value, pretessellated: the carpet bugs have something fluffy to hide again :)

But, of course, 2.7.1 grass will be much better for close-ups and wooly British bathroom carpeting :D

Li'l one minute test, itchy and scratchy as desired.

[eric nixon]

Try to reduce the settings so that its only using about half a gig of ram, combine with r2+ bump, and then its a useful carpet. good-luck.

[eric nixon]

I had a go at making a carpet, (well it was supposed to be a jumper but I realise we need 3d disp to get a proper wool effect), anyway I used this mxm from the gallery 'argyle jumper' it has a 'fur' disp map and gives a good towel / short fur effect.

On-the-fly makes the most sense for fine low-height displacement, I used subdiv 4 on the relatively high-poly simball mesh, but this isnt high enough to describe the fine detail of the map, so the same map is also used as a bump map to reinforce the detail.

Doesnt use much ram, no voxelisation.. 8 min render

[eric nixon]

another try with a simple spotty noise disp map, 20 min sl14, bit slower because a little lambert trans added to 'tips'. And the finished jumper sl18.

[simmsimaging]

Those look great Eric.

[eric nixon]

Here is the same material on a flat cube (floor) because there is a tiny bit of transparency I put an opaque plane intersecting the underside of the carpet ( a bit like carpet backing...) so theres about 1 cm deep carpet, then backing, you can see in the shadow of the buddha thats theres less actual disp tufts and quite a lot of bump map... hope that makes sense.



I had to change the on-the-fly disp form a percentage to a fixed height, which makes sense because carpet-tufts tend to be fixed size no matter how big the carpet.. anyway using a percentage in this case gives unpredictable results, even when all the polys are roughly the same size?

[simmsimaging]

very convincing result. Nice.