APS grass - help please

[Pavlov]

Hi,
after some deludent experiment with APS, i removed it from my pipeline time ago. It always goes out of memory for decent looking fibers on large areas.
Yesteday i told myself it0s not possible Lw has not a decent displacement system so i messed with it a bit again, but no way.
Even using pixels per poly, or gradients based on distance, or subdividing the plane more and using per poly subd, i couldnt get APS to get dense subdivision near camera and lower in the distance.
Actually i didnt find a way to get decent grass - or rug - displacement on relatively large areas. So i ask for help: can someone show me a good looking grass plane setup done in APS ?

Paolo

[-EsHrA-]

hmmm i tried it too...but not really convincing.
i sorta gave up on that for now.

more enhancements needed in lw.


mlon

[Pavlov]

Sure, in particular an industry standard Displacement system is needed.
I didnt read many comments on APS usage, so it's better to let NT know this is not an efficent technology.
As said, current system is not suited to handle small details on large areas. Only large details on large areas, or small details on small areas.
Hope a common MPD system (like you can find in any other software) will replace this one asap.

Paolo

[Iain]

Paulo
This was the main reason I started the "We Need VRay for LW" thread. Of all the things that stood out in the images I posted there, the displacement was probably the most impressive.
Some thought they could emulate it easily in LW but they couldn't, not to even remotely the same quality.

Displacement like that in Vray opens doors for a whole load of stuff we have to fudge: grass, fur, sand, puddles in uneven ground etc, etc.

[Pavlov]

yes. A true, professional displacement is on the plans for Kray, but this is not a reason for Lw to miss such a fundamental feature.

Paolo

[Iain]

Paulo was a typo btw. I do know your name-sorry!

[Matt]

I too was excited when APS was announced, but quickly gave up like everyone else after I realised I couldn't do anything useful without it running
out of memory.

It seems like it was a bit of a hack until the core is structured in a way that allows _proper_ sub-pixel displacement.

Maxwell Render's displacement solution look very cool, something like that would be welcome.

[WilliamVaughan]

I use APS all the time without running out of memory. With that said ...I use APS for Per Polygon Level and control it with gradients.

[COBRASoft]

I think a new tutorial about APS is coming up :)

[Pavlov]

Matt, sure i cant exclude i'm doing something wrong... can you show me some stuff like believable grass or shrug done in APS , and most important the setup ?
Hope Proton will cover this aspect in a tutorial, i would wellcome a solution since by now i'm nearly using LW as if it had no displacement at all.

paolo

[JeffrySG]

Have you watched any of these videos? They may help a bit...

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/Displacement_APS.mov

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/APS_PerPolygon.avi

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/FurDisplacement.mov

--Jeff

[Iain]

Yeah come on Proton, if anyone can get something useful out of LW displacement, my money's on you.

And I'm not talking a nice stone relief or basic fur. Something like believable grass or a long pile rug. (Please!)

[Pavlov]

yes... i looked at these movies (again in two cases) but doing a furry ball is something i can do without problems. As said i want to see if LW's displacement can handle (in a believable way) production situations too, like believable small details on large areas (grass on a 100m plane, pebbles on a square, shingles on roofs).

Paolo

[Iain]

Have you watched any of these videos? They may help a bit...

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/Displacement_APS.mov

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/APS_PerPolygon.avi

ftp://ftp.newtek.com/products/LightWave/Trial/Videos/FurDisplacement.mov

--Jeff

The Fur Displacement one is very useful and informative. I experimented with that technique on a front lawn and it was looking good till I rendered the high res image and everything just went belly up.

Maybe I just need a better pc.

[-EsHrA-]

"Maybe I just need a better pc."

Maybe we need a better lw?!

That said, id love to see Protons try.


mlon

[Mitja]

I gave it a try, and I must say it's not so bad, though not the best. Considering that I spent, say 10 mins including render ( on a p4), the result is acceptable, for me. With some further work could be improved. Say what do you think!
(PS: render 5mins, 82MB memory eaten)
53704

[Pavlov]

Mitja, thanks for trying. it's not bad, but i woulndt use this grass in production.
It's too off-scale,, grass normally is not moer than 8-10 cm high and it's more dense. I seem also to see some MB trick, and i really dont want to be forced to make moer passes just because dosplacement cannot reach desired level - correct me if i'm wrong about MB.
Usually, grass needs a very high detail near camera - from 0 to 10 m, then it can fade gradually to a simple texture. Probably APS could do it, but i have issues in getting a correct gradient on subdivision using logical methods - a distance to camera gradient.
Maybe it's just a camera issue ? i'll try now with a null parented to camera to see if it works.

Paolo

[Mitja]

It's too off-scale,, grass normally is not moer than 8-10 cm high and it's more dense. I seem also to see some MB trick, and i really dont want to be forced to make moer passes just because dosplacement cannot reach desired level - correct me if i'm wrong about MB.
Maybe it's really out of scale: I could just size up the "house", or lower the grass. The density could be higher too. Since it's just a test I wouldn't stop so long on these details (which can be corrected): I think the overall look is quite as Sas. I used MB, but since you must use AA anyway I can't see where the problem is. Anyways, could you post your previous tests?
I guess that an issue is also the fact that this technique can't be used with KRay/FPrime, am I right?
About the distance to camera: I dunno, should try! Personally I would use this only for larger lawns with huge amount of grass...boh!:)
PS: what does it mean - moer?

[Andyjaggy]

I think APS works rather well. I don't it is APS that is the main problem. I think it is the way LW handles memory and displacements that is the issue. Having to generate and hold the entire mesh in memory.......... I can't think of a worse way of doing it.

[arrow1234]

i tried using APS grass before (there should be a video tutorial somewhere on newtek) and i gave up. It was running outta memory, i guess my grass area is way too huge. Same thing as Sas, it wont let me render for the second time due to the memory issue.
did you try HD instancing large area of grass, it may work :)